无家可归者多地点结核病传播

地点：2002-2003年，在华盛顿King县，结核病（TB）在多个收容所的人群中大规模爆发。 目的：控制结核病在多个地点的传播。设计：2002年，对收容所病人的接触者进行筛查，作结核菌素皮试（TSTs）和症状回顾。根据这些筛查的结果，确定和优选传播的地点。2003年，对暴露于这些点的队列作彻底的筛查（例如，症状回顾，TST，胸部X线检查[CXR]，痰检和痰培养）。利用PCR为基础的方法对从病人那里分离出来的结核分枝杆菌作基因分型，以快速确认爆发相关病人。 结果：2002-2003年，King县313例确诊的病人中有48例（15％）与爆发相关；通过基因分型，47例培阳病人分离出和爆发相匹配的菌株。3个收容所由于在2002年接纳的病人超过12人，所以人群中TST阳性率（约30％）高于收容所中的一般水平（7％）。用一个痰培养筛查接触者和CXR发现结核病人的敏感度相似（分别为77％和62％）。 结论：一个广泛的资源密集的途径可能有助于控制疾病的传播。这次爆发突显出无家可归者的脆弱性和在城市维持强有力的结核病规划的必要性。     

Wallstent metallic biliary endoprosthesis: MR imaging characteristics.

Image quality and safety of magnetic resonance (MR) imaging were evaluated in vitro and in eight patients with the most commonly employed metallic biliary endoprosthesis. In vitro, the stent produced no tip deflection at 0.6 or 1.5 T. Trace magnetic susceptibility artifact, similar to artifact from a column of air, paralleled the stent. In patients, image degradation was minimal with conventional pulse sequences. Middle-field-strength spin-echo images revealed minimal artifacts indistinguishable from those produced by pneumobilia.     

The use of methotrexate in steroid-resistant systemic lupus erythematosus

Although the use of methotrexate (MTX) is gaining acceptance in the treatment of several connective tissue diseases, there is little evidence of its therapeutic value in systemic lupus erythematosus (SLE). We examined the response to MTX in patients with steroid-resistant SLE in an open, unblinded study. Of 10 SLE patients treated with MTX (7.5 mg/weekly), 7 showed improvement. The other 3 stopped therapy because of lack of response or because of side effects. Improvements were noted within 3 months in responding patients. These promising observations suggest that controlled studies of MTX for the treatment of SLE are justified.     

The association between water fluoridation and hip fracture among white women and men aged 65 years and older. A national ecologic study.

For the past 45 years, there has been a great deal of debate regarding the health issues surrounding the fluoridation of public water supplies. In order to assess the association between fluoridation and hip fracture, we identified 129 counties across the United States considered to be exposed to public water fluoridation and 194 counties without exposure. Data from the Health Care Financing Administration and the Department of Veterans Affairs were used to calculate the incidence of hip fracture among white persons, aged 65 years or older, in fluoridated and nonfluoridated counties. There was a small statistically significant positive association between fracture rates and fluoridation. The relative risk (95% confidence interval) of fracture in fluoridated counties compared to nonfluoridated counties was 1.08 (1.06 to 1.10) for women and 1.17 (1.13 to 1.22) for men. As comparisons were made at the grouped level, it may be inappropriate at this time to draw inferences at the individual level. The relationship observed at the county level needs to be duplicated at the individual level with more precise measures of fluoride exposure.     

Anesthesia and/or Sedation for Pulsed Dye Laser Therapy

One of the most exciting developments in pediatric dermatology has been the use of the flashlamp-pumped, 585-nm, pulsed dye laser for treatment of vascular birthmarks. In many cases the results are miraculous. The increase in self-esteem and happiness of many children and adolescents has been overwhelming; for some, depression has been lifted, stuttering has ceased, social involvement has increased, and antidepressants have been discontinued. There are many success stories to tell.
Despite the remarkable effects of the pulsed dye laser and the medical and psychosocial indications for its use, the issue of pain control remains significant. We have no perfect outpatient pediatric anesthetic. Most methods carry either some risk or, if not hazardous, often are not very effective for controlling pain. Needless to say, a diversity of opinions exist on how to manage discomfort from this treatment modality. Therefore, we thought it would be useful to share the experiences and opinions of several dermatologists who have extensive experience with the pulsed dye laser.     

The relationship between receptor-effector unit heterogeneity and the shape of the concentration-effect profile: Pharmacodynamic implications

The apparent concentration-effect relationship is the ensemble of many effector units (such as individual cells or channels) that do not always exhibit a uniform stimulus-effect relationship. This concept is substantiated by many observations of heterogeneity in receptor-effector populations including hormone secreting cells, response to hormonal stimuli, activity pattern of second messengers, stimulus-evoked synaptic currents, and single ion channels. The relationship between drug concentration and magnitude of pharmacologic response is commonly described by the sigmoidalE _max model which was derived from the Hill equation. The sigmoidicity factor (N) in this model is assumed to be a pure mathematical parameter without physiological connotations. This work demonstrates that the numerical value ofN (measured empirically) is the product of two factors: (i) the degree of heterogeneity of the effector subunits, i.e., the elemental component that upon drug stimulus contributes its pharmacological effect independently and does not interact with other subunits (it could range from a single receptor up to a whole tissue), and (ii) value ofN ^*—the shape factor of the subunits' concentration-effect relationship. A special case of this approach occurs whenN ^*>5, which is an on-off case. HereN is determined by the distribution (density equation) of the subunit values. In case of heterogeneity of the microparameters of the effector subunits the apparentN will always have a lower value thanN ^*. According to this theory it can be concluded that without knowledge of the distribution of the microparameters no mechanistic interpretation can be deduced from the apparentN value. If in the futureN ^* can be determined by theoretical or experimental methods, the distribution function relatingN ^* toN can be calculated. The relevance of this theory is increased in view of the progress being made in advanced research techniques which may enable us to determine the concentration-effect relationship at the level of the individual effector unit.     

Proctocolectomy and ileoanal anastomosis with an S pouch: functional results

Patients with total colonic ulcerative colitis or familial polyposis traditionally require a proctocolectomy. In an effort to preserve the normal pathway for defecation and avoid the nuisance of an abdominal stoma, a continence-preserving procedure involving a pelvic reservoir has been performed at the University of Minnesota Hospitals on 120 patients. The majority were operated on for colonic ulcerative colitis. There were no deaths. The mean hospital stay after restorative proctocolectomy was 10 days and after ileostomy takedown the mean stay was 7 days. Functional results were assessed in 52 patients. Daytime bowel movements averaged 6.4 and night-time movements 1.4. Major daytime incontinence occurred in 6% of the patients, 21% had moderate soiling at night and 70% wore a perineal pad in the evening. Ninety-two percent of the patients expressed satisfaction with the procedure. The most serious complication was pelvic sepsis. It occurred in nine patients, six of whom required subsequent surgery. The Parks S pouch provides a means of maintaining anal continence. This series and others have shown that young, healthy, well-motivated persons will benefit most from a restorative proctocolectomy.