The role of sentinel node biopsy in the management of melanocytic lesions of uncertain malignant potential (MUMP).

Melanocytic lesions of uncertain malignant potential (MUMP) is a term which is useful in identifying melanocytic tumours where the distinction between benign and malignant is a histological problem. Sentinel node biopsy is recognised to provide unmatched prognostic information in melanoma patients, but has recently been advocated for diagnostic purposes in MUMP. We present the case of a seven-year-old girl who presented with a six-month history of a changing pigmented lesion on her left upper arm. Excision biopsy not only showed a melanocytic lesion with some spitzoid features but also marked atypia making it appropriate to use the term MUMP. Sentinel node biopsy was undertaken. This case demonstrates that sentinel node biopsy can be performed safely in children. Given the low morbidity of the procedure we advocate that this technique should be considered in this difficult diagnostic situation to further the management of these patients.     

Reversal theory constructs and cigarette availability predict lapse early in smoking cessation

The purpose of this study was to investigate the contribution of reversal theory constructs (i.e., metamotivational states) to understanding the outcome of tempting situations thatoccur in the first 6 weeks of smoking cessation. Cessation program participants (N = 68) were interviewed about tempting situations in which they either smoked or maintained abstinence. Both independent groups and repeated measures analyses indicated that metamotivational state (serious and goal-directed vs. playful and spontaneous) and cigarette availability significantly predicted outcome. Reversal theory constructs correctly predicted outcome of the tempting episode for 70% of the subjects, while cigarette availability was an accurate predictor for 74%. Metamotivational state and cigarette availability together predicted the outcome for 89% of the subjects. ©1995 John Wiley & Sons, Inc.     

A Pneumatic Device for Rapid Loading of DNA Sequencing Gels

This work describes the design and construction of a device that facilitates the loading of DNA samples onto polyacrylamide gels for detection in the Perkin Elmer/Applied Biosystems (PE/ABI) 373 and 377 DNA sequencing instruments. The device is mounted onto the existing gel cassettes and makes the process of loading high-density gels less cumbersome while the associated time and errors are reduced. The principle of operation includes the simultaneous transfer of the entire batch of samples, in which a spring-loaded air cylinder generates positive pressure and flexible silica capillaries transfer the samples. A retractable capillary array carrier allows the delivery ends of the capillaries to be held up clear of the gel during loader attachment on the gel plates, while enabling their insertion in the gel wells once the device is securely mounted. Gel-loading devices capable of simultaneously transferring 72 samples onto the PE/ABI 373 and 377 are currently being used in our production sequencing groups while a 96-sample transfer prototype undergoes testing.     

MHC-restricted autoantigen-reactive T cell clones in multiple sclerosis

Multiple sclerosis is a demyelinating disease of the central nervous system with genetic, viral and autoimmune characteristics. Myelin basic protein (MBP) is a suspected target autoantigen since it induces experimental autoimmune encephalomyelitis, an animal model closely resembling multiple sclerosis. The disease is mediated by Class II restricted, MBP-reactive T cells possessing the T helper/inducer phenotype. In the present study, we have isolated MBP-reactive T cell clones from the peripheral blood of a chronic progressive multiple sclerosis patient. The clones displayed blastogenic memory responses when rechallenged with the autoantigen and irradiated autologous lymphocytes. MBP recognition by the autoantigen-reactive T lymphocytes was restricted by major histocompatibility complex Class II antigens. Both CD4+8- and CD4-8+ MBP-reactive T cell clones were obtained.     

Non-linkage of the islet amyloid polypeptide gene with Type 2 (non-insulin-dependent) diabetes mellitus

Summary Type 2 (non-insulin-dependent) diabetes is associated with the deposition of islet amyloid. The major formative peptide, islet amyloid polypeptide, has recently been characterised and an abnormality of the structure or expression of this gene is a possible candidate for the inherited component of Type 2 diabetes. A restriction fragment length polymorphism of the gene has been identified with Pvu II. To study the relationship between the islet amyloid polypeptide gene and Type 2 diabetes, two distinct genetic approaches have been undertaken. Firstly, non-linkage has been demonstrated in four pedigrees, with four normoglycaemic first degree relatives having an allele associated with diabetes in other family members, and one affected relative not having the putatively associated allele. The LOD score taking age-related penetrance into account was –1.68, making linkage unlikely (p=0.02). Secondly, in a population-based restriction fragment length polymorphism survey, no linkage disequilibrium of the alleles was found between a population of unrelated Caucasian subjects with Type 2 diabetes and a normal population. A mutation in or near the islet amyloid polypeptide gene is thus unlikely to be a common cause of Type 2 diabetes.     

Computed radiography in musculoskeletal imaging: state of the art.

Computed radiography is a 2K x 2K x 10 bit digital radiographic system that replaces the film-screen combination with a photo-stimulable phosphor plate. The advantages of this relatively new technology include linear detector response, improved detector efficiency, and digital processing capabilities. Musculoskeletal applications benefit significantly from these attributes, which result clinically in the ability to reduce both radiation dose and number of exposures. Studies of observers' performance have shown no statistically significant difference in diagnostic accuracy between film-screen and computed radiographic musculoskeletal images. Computed radiography is particularly useful in the evaluation of the musculoskeletal system in traumatized patients with portable radiographs, spine radiographs, scoliosis studies, and depiction of soft-tissue abnormalities. Limitations include change in image format and size, high cost, decreased spatial resolution, restricted throughput, increased perception of noise, and new artifacts that must be recognized. Spatial resolution limitations of computed radiography in identification of fine detail information can be improved by using magnification techniques. Radiation dose reduction with an exposure decrease of 25-50% can be achieved without loss of diagnostic accuracy, although this depends on the examination and the abnormality. An interactive workstation is important in the use of a computed radiographic system with capabilities to adjust display parameters to best depict images and disease. We conclude that computed radiography is an alternative to film-screen radiography without significant differences in diagnostic quality in the evaluation of musculoskeletal images.     

Effects of cholestyramine on gallbladder and gastric emptying in obese and lean subjects

Abstract. Gallbladder stasis is frequent in obese subjects and may contribute to their increased risk for gallstone formation. The bile salt sequestrant cholestyramine acutely enhances postprandial gallbladder emptying in lean subjects, through dis-inhibition of a negative feedback between intraluminal bile salts and CCK release. In this study the effect of cholestyramine on both gallbladder and gastric antrum dynamics were studied by realtime ultrasonography in 12 obese and 15 lean subjects. For the acute study, on different days, subjects ingested a liquid meal (two egg yolks plus water 200 mL, 50 kJ) or a meal with 4g cholestyramine. Gallbladder emptying was impaired in obese patients who had significantly larger fasting gallbladder volume (39.4 ± 6.9 vs. 21.6 ± l.7mL, P <0.02), larger residual volume (12.3 ± 1.8 vs. 4.0 ± 0.5ml, P < 0.0006) and slower emptying time ( T /2: 33 ± 2 vs. 21 ± 2 min, P < 0.05) than lean subjects. Integrated antral emptying was also less in obese than lean subjects (5521 ± 578 vs. 7908 ± 491 % 120min^-1, P <0.02). Cholestyramine enhanced postprandial gallbladder emptying in both obese and lean subjects. Gastric emptying was delayed with cholestyramine in lean but not obese subjects. For the chronic study, after 1 month therapy with cholestyramine (4 g every 2 days), the motility tests were repeated in nine obese subjects. Gallbladder and gastric responses to a test meal, with or without cholestyramine, were preserved. We conclude that both gallbladder and antral emptying of a liquid test meal are impaired in obese subjects. Gallbladder emptying improves after acute administration of a low dose cholestyramine with test meal. This effect is sustained after 1 month treatment with a low dose of cholestyramine and does not interfere with gastric emptying of obese patients. Cholestyramine may improve gallbladder hypomotility in obese people.