A population-based study of migraine headaches in Olmsted County, Minnesota. Case ascertainment and classification.

Using the unique resources of the Rochester Epidemiology Project for population-based studies, we identified 629 Olmsted County, Minn., residents who fulfilled the 1988 International Headache Society criteria for newly diagnosed migraine over a 3-year period. Over 6,400 patient records from several diagnostic rubrics were screened; a substantial proportion of cases had been 'signed-out' to diagnoses other than 'migraine headache'. Medical records were reviewed by two trained nurses who abstracted supporting data for two neurologists. The neurologists determined whether each case met eligibility requirements and assigned a headache diagnosis by consensus. The diagnostic criteria offered some flexibility and were adapted to retrospective record-based research. Most records contained enough information to effectively classify the headache, although information on the frequency and duration of attacks proved to be problematic. A validation re-abstraction of a 10% sample of cases was undertaken with acceptable reproducibility of symptoms and diagnosis. Our study shows that migraine headache can be studied retrospectively through existing detailed medical records.     

CT appearance of cervical lipoblastoma

We describe a case of lipoblastoma causing respiratory symptoms in an infant, where CT was useful in establishing the diagnosis and demonstrating the extent of involvement so that complete surgical resection could be planned.     

Enterohepatic circulation of T-2 toxin metabolites in the rat

The enterohepatic circulation of T-2 toxin and its conjugated metabolites was examined in bile duct-cannulated male rats. Rats administered tritiated T-2 toxin intraduodenally (id) eliminated 44.65% and 57.25% of the administered dose in the bile within 4 and 8 hr post-dosing, respectively. TLC profiles of the T-2 metabolites were similar after intravascular and id administration. The major metabolites detected were 3'-OH-hydroxytryptamine-2 (HT-2), glucuronic acid conjugates, T-2 tetraol (TOL), 4-deacetylneosolaniol (4-DN), and HT-2. Tritium-labeled glucuronides obtained from the bile of rats administered [3H]T-2 toxin intravascularly were extracted and purified using C-18 and silica column chromatography. Enzymatic hydrolysis followed by TLC and GC/MS indicated that the aglycone portion of the glucuronides were composed of 3'-OH HT-2, HT-2, 4-DN, and TOL. After id administration of the glucuronides the rats eliminated 6.01% (4 hr) and 11.86% (8 hr) of the dose in the bile. No free metabolites of T-2 toxin were detected in the bile of any animals administered the purified glucuronides. Oral treatment of the rats with the beta-glucuronidase inhibitor, saccharolactone, did not produce a significant decline in the amount of radioactivity recovered in the bile following administration of the tritium-labeled glucuronides. These studies substantiate the enterohepatic circulation of T-2 toxin metabolites.     

Interferon-gamma knockout fails to confer protection against obliteration in heterotopic murine tracheal allografts.

BACKGROUND: Interferon-gamma, produced by T-helper cells, activates macrophages and increases expression of major histocompatibility complex (MHC) products in acute and chronic rejection. We investigated the role of interferon-gamma in murine heterotopic tracheal allografts. METHODS: Tracheas from BALB/c mice were heterotopically transplanted to BALB/c (12 isografts: 2 weeks [n = 6] and 4 weeks [n = 6], C57BL/6 (12 allografts: 2 weeks [n = 6] and 4 weeks [n = 6]) and C57BL/6 interferon-gamma knockout mice (12 interferon-gamma knockout allografts: 2 weeks [n = 4] and 4 weeks [n = 8]). BALB/c interferon-gamma knockout tracheas were transplanted to C57BL/6 mice (reverse knockout: 4 weeks [n = 6]) and BALB/c interferon-gamma knockout mice (4 weeks [n = 2]). C57BL/6 tracheas were transplanted to Bm12 mice (MHC Class II mismatch allografts: 4 weeks [n = 6]). Conventional histology and immunohistochemistry for CD4, CD8 and CD11b were performed. RESULTS: Minimal (<20%) obliteration was seen at 2 weeks in the allograft groups. No obliteration was seen in the isograft groups. However, all allografts were completely obliterated at 4 weeks. Interferon-gamma knockout allograft combinations displayed severe rejection characterized by intense intra- and extraluminal infiltration by CD4-, CD8- and CD11b-labeled cells. The MHC Class II mismatch allograft group showed normal epithelium and mild sub-epithelial infiltration by CD4+ cells at 4 weeks (CD8-, CD11b-). CONCLUSIONS: Absence of interferon-gamma does not protect the allograft from obliteration. Epithelial destruction by cytotoxic T cells appears to be an important mechanism in the development of obliteration in murine heterotopic tracheal allografts.     

Serum levels of specific glucuronidated androgen metabolites predict BMD and prostate volume in elderly men.

Androgens are important regulators of bone and prostate health in elderly men. The role of serum levels of glucuronidated androgen metabolites as predictors of BMD and prostate volume in men is unclear. We show that specific glucuronidated androgen metabolites predict BMD and prostate volume in elderly men. INTRODUCTION: Androgens are important regulators of bone and prostate health in elderly men. Local synthesis and degradation of androgens are likely to be important parameters of biological action of androgens in androgen-responsive tissues. The aim of this study was to determine the role of serum levels of glucuronidated androgen metabolites as predictors of BMD and prostate volume in elderly men. MATERIALS AND METHODS: A subsample of the population-based Swedish part of the MrOS study (n = 631, average age = 75.9 years) was investigated. Bone parameters were measured using DXA. Serum levels of total testosterone (T) and dihydrotestosterone (DHT) were measured by gas chromatography/mass spectroscopy (GC-MS); androstane-3alpha,17beta-diol-3glucuronide (3G) and androstane-3alpha,17beta-diol-17glucuronide (17G) were measured by liquid chromatography/mass spectroscopy. Prostate volume (n = 159) was measured by transrectal ultrasound. RESULTS: The general pattern is that two of the glucuronidated androgen metabolites, namely 17G and 3G, are stronger positive predictors of BMD than the bioactive androgens (T and DHT). In addition, 17G is a clear positive predictor of prostate volume, explaining 4.5% of the variance in prostate volume, whereas the bioactive androgens do not display any association with prostate volume. CONCLUSIONS: Serum levels of specific glucuronidated androgen metabolites predict BMD and prostate volume in elderly men. Future studies should determine if the glucuronidated androgen metabolites also reflect other biological correlates of androgenic activity, including prostate cancer, and if low levels might be a marker of general androgen deficiency in men.     

Correlates of nonparticipation in an HIV prevention program for MSM.

Providing HIV prevention services to high-risk individuals remains challenging. We assessed factors associated with nonparticipation among high-risk, sexually active MSM found eligible to participate in a brief, telephone-delivered HIV prevention trial designed to evaluate the efficacy of motivational enhancement therapy (the Sex Check). Two levels of nonparticipation are evaluated: eligible participants who did versus those who did not complete their baseline/enrollment interview, and enrolled participants who did versus those who did not attend any of their counseling sessions. Nonenrollers were younger, less educated, more closeted, and were more likely to report sex with an injection drug using partner. Enrolled participants who did not engage in their counseling session(s) were less educated, reported greater use of alcohol and drugs during sex and use of injection drugs. Innovative methods to reduce barriers to engaging high-risk, sexually active MSM in risk reduction counseling are needed.