Dysphagia in patients with inclusion body myositis

OBJECTIVE: To determine whether ampicillin- and tetracycline-resistant strains of Pasteurella multocida and P haemolytica isolated from California cattle with pneumonia were spatially and temporally clustered and to compare overall estimates of percentages of these isolates resistant to these antimicrobials with estimates obtained on the basis of regional and temporal information. DESIGN: Epidemiologic study. SAMPLE POPULATION: Records of P multocida and P haemolytica isolates obtained from lung or tracheal wash samples collected from California cattle with pneumonia between July 1, 1991 and July 31, 1996. Only isolates obtained from samples submitted by dairies and calf ranches were used. PROCEDURE: Spatial clustering of ampicillin- and tetracycline-resistant isolates was assessed by use of nearest-neighbor and Cuzick and Edwards' analyses. Linear clustering along a north-south line was assessed by use of runs and maximum length of runs tests. Temporal clustering was assessed by use of scan tests. Spatial-temporal clustering was assessed by use of Barton's method. Regional estimates of percentages of P multocida and P haemolytica resistant to ampicillin or tetracycline were calculated. RESULTS: There was significant spatial clustering of resistant isolates and significant linear clustering along a north-south line. Significant differences in regional estimates of percentages of antimicrobial-resistant isolates were found. CLINICAL IMPLICATIONS: Results support the hypothesis that antimicrobial-resistant organisms can be clustered at the local level and reinforce the need to establish regional estimates of percentages of bacterial isolates that will be susceptible to commonly used antimicrobials.     

Intrapulmonary steady-state concentrations of clarithromycin and azithromycin in healthy adult volunteers

The steady-state concentrations of clarithromycin and azithromycin in plasma were compared with concomitant concentrations in epithelial lining fluid (ELF) and alveolar macrophages (AM) obtained in intrapulmonary samples during bronchoscopy and bronchoalveolar lavage from 40 healthy, nonsmoking adult volunteers. Mean plasma clarithromycin, 14-(R)-hydroxyclarithromycin, and azithromycin concentrations were similar to those previously reported. Clarithromycin was extensively concentrated in ELF (range of mean +/- standard deviation concentrations, 34.4 +/- 29.3 microg/ml at 4 h to 4.6 +/- 3.7 microg/ml at 24 h) and AM (480 +/- 533 microg/ml at 4 h to 99 +/- 50 microg/ml at 24 h). The concentrations of azithromycin in ELF were 1.01 +/- 0.45 microg/ml at 4 h to 1.22 +/- 0.59 microg/ml at 24 h, and those in AM were 42.7 +/- 28.7 microg/ml at 4 h to 41.7 +/- 12.1 microg/ml at 24 h. The concentrations of 14-(R)-hydroxyclarithromycin in the AM ranged from 89.3 +/- 52.8 microg/ml at 4 h to 31.3 +/- 17.7 microg/ml at 24 h. During the period of 24 h after drug administration, azithromycin and clarithromycin achieved mean concentrations in ELF and AM higher than the concomitant concentrations in plasma.     

Pregnancy and iron deficiency: unresolved issues

Iron deficiency and iron deficiency anemia are prevalent among pregnant women. The extent to which iron deficiency affects maternal and neonatal health is uncertain. Existing data suggest that maternal iron deficiency anemia may be associated with adverse outcomes, including preterm delivery and higher maternal mortality. Further research is needed on the maternal and neonatal benefits of iron supplementation during pregnancy.     

Developing systems for cost-effective auditing of clinical trials

Auditing a clinical trial is a complex process designed to ensure that the trial will provide a reliable answer to the question being posed. Traditional auditing methods are expensive, and escalate the cost of clinical trials. This paper describes approaches to cost-effective monitoring of clinical trials, such as integrating them with clinical practice and focusing the data being collected. Sampling methods for source documentation can be used to eliminate costs incurred by reviewing every record. These measures, coupled with prospective clinical judgment about areas of concern in the conduct of trials, can reduce complications and costs without sacrificing quality.     

Satisfaction with inpatient acquired immunodeficiency syndrome care. A national comparison of dedicated and scattered-bed units

OBJECTIVES: This study sought to determine whether there were differences in acquired immunodeficiency syndrome (AIDS) patients' satisfaction with inpatient nursing care on dedicated AIDS units compared with conventional, multidiagnosis medical units. METHODS: Interview data were collected from more than 600 consecutive AIDS admissions in 40 patient care units in 20 hospitals in 11 high AIDS incidence cities. Ten hospitals with dedicated AIDS units were matched with comparable hospitals treating AIDS patients on multidiagnosis medical units. AIDS patients' satisfaction with nursing care on dedicated AIDS units was compared with AIDS patients' satisfaction with care on scattered-bed units in the same hospital and with AIDS patients' satisfaction on scattered-bed units in different, matched hospitals without dedicated units. Interhospital differences that were not controlled by design were controlled statistically, as were differences in patient characteristics and illness severity. RESULTS: Acquired immunodeficiency syndrome patients receiving care on dedicated AIDS units were significantly more satisfied with their nursing care. In hospitals with units of both types, dedicated AIDS units had a higher proportion of white patients, men, and homosexuals, whereas scattered-bed units had more minority patients and intravenous drug users. Controlling for these factors as well as for differences in illness severity and interhospital differences in patient satisfaction did not diminish the positive AIDS unit effect on patient satisfaction. CONCLUSIONS: Dedicated AIDS units achieve higher levels of satisfaction among patients with AIDS than general medical units. There is no evidence that patients feel isolated or stigmatized on dedicated AIDS units compared with patients on general units, and many patients have a clear preference for dedicated units.     

Cryogen spray cooling during Nd:YAG laser treatment of hemangiomas. A preliminary animal model study

BACKGROUND: Successful laser treatment of hemangiomas requires selective photothermal destruction of dilated cutaneous vessels without damaging the overlying epidermis. Delivering a short cryogen spurt, on the order of milliseconds, has been shown to result in localized cooling of the superficial skin structures during laser irradiation. OBJECTIVE: The purpose of this study was to examine the effectiveness of cryogen spray cooling (CSC) in protecting superficial tissue structures during continuous Nd:YAG laser irradiation of an in vivo model hemangioma. METHODS: The highly vascularized chicken comb was selected as the animal model for hemangiomas. The Nd:YAG laser irradiation ranged from 2.6 to 35.1 J/mm2. A feedback system utilizing infrared radiometry monitored the comb surface temperature and controlled delivery time of the cryogen spurt. When comb surface temperature during laser irradiation reached 36-42 degrees C, a 30-100 msec cryogen spurt was delivered. Animals were euthanized 1 hour to 21 days following each experiment. Gross and histologic analyses were performed. RESULTS: Nd:YAG laser irradiation resulted in deep (up to 6.1 mm) tissue photocoagulation, while CSC preserved the overlying epidermis and papillary dermis. CONCLUSION: The results demonstrate that CSC is effective in protecting the epidermis and papillary dermis, while achieving deep tissue photocoagulation during Nd:YAG laser irradiation. Further pilot studies in humans appear warranted.     

Tumor involvement in hepatic veins: comparison of MR imaging and US for preoperative assessment

PURPOSE: To compare use of magnetic resonance (MR) imaging and ultrasonography (US) for diagnosis of vascular involvement by tumor at the hepatic vein confluence. MATERIALS AND METHODS: Thirty-seven consecutive patients with tumors at the hepatic vein confluence were prospectively evaluated with spin-echo and gradient-echo MR imaging and gray-scale and Doppler US. Encasement, thrombosis, occlusion, and nonvisualization were considered to be evidence of vascular involvement. Imaging results were compared with surgical and pathologic examination findings in 27 patients who underwent resection. RESULTS: Sixteen hepatic veins (nine right, four middle, three left) were seen to be involved at surgery. Twelve of 16 involved veins were identified at MR imaging (75% sensitivity, 98% specificity, 92% positive predictive value, 94% negative predictive value). Thirteen of 16 involved veins were detected at US (81% sensitivity, 97% specificity, and 87% positive and 95% negative predictive values). There was one false-positive diagnosis of inferior vena cava involvement at both MR imaging and US. Ten patients had unresectable disease. One patient had motion artifact on MR images; in the remaining nine patients, MR imaging and US yielded identical findings at 26 of 27 hepatic vein sites. CONCLUSION: MR imaging and US provide comparable results for assessment of hepatic vein involvement by tumor.     

Trends toward a national health care marketplace

In the last two decades, the term "quality-of-life" has become popular in medicine and health care. There are, however, important differences in the meaning and the use of the term. The message of all quality-of-life talk is that medicine and health care are not valuable in themselves. They are valuable to the extent that they contribute to the quality of life of patients. The ultimate aims of medicine and health care are not health or prolongation of life as such, but preservation or improvement of the quality of life. The primary aims of medicine and health care, such as the prolongation of life, can--but need not always--come into conflict with the ultimate ones: medical treatments do not always benefit a patient. In this article I will, first, summarize the results of my explorations of the use and the meaning of the term "quality-of-life." The use and the meaning of the term turn out to depend on the contexts of medical decision-making in which it is used. I will show that there are at least three different concepts of quality-of-life. Second, I will argue that the different concepts of quality-of-life are not unrelated. They point to different components of and/or conditions for happiness. Third, I will analyze the relation between the three concepts of quality-of-life, health and happiness.     

Plasma-modified nylon meshes as supports for cell culturing

The polymeric surfaces of three commercially available nylon films with mesh openings of 5 microns, 10 microns and 20 microns were treated with anhydrous ammonia gaseous plasma. Cells cultured on the plasma-treated nylon films have higher proliferation rate and assume morphology distinct from those cultured on the unmodified films. Of the three plasma-modified membranes, the one with 5 microns mesh openings supported a largest population of cell growth. The plasma-treated nylon meshes provided a stronger anchorage for the collagen matrices formed within the mesh openings. Application of this collagen/nylon meshes for cell culturing is demonstrated.     

Effect of molecular weight on the diffusion of contrast media into cartilage

STUDY DESIGN: A comparison of contrast enhancement in the intervertebral disc from two magnetic resonance imaging contrast media in experimental animals. OBJECTIVES: To test the effect of molecular weight on the diffusion of ionic contrast media into the intervertebral disc. SUMMARY OF BACKGROUND DATA: Intravenously administered gadopentetate diffuses similarly into the fibrocartilage of intervertebral discs and herniated disc fragments. Differentiation between recurrent disc fragments and scar tissue via magnetic resonance imaging is optimized by using contrast media, which result in different contrast enhancement of these two tissues. Contrast media of higher molecular weight diffuse more slowly into cartilage; hypothetically, therefore, such media will produce better contrast between scar tissue and recurrent disc fragments. METHODS: Gadopentetate (molecular weight 546) or gadolinium-polylysine (molecular weight 40,000) was injected intravenously into rabbits. The signal intensities of intervertebral disc and muscle tissue were recorded by magnetic resonance imaging at baseline and at pre-determined intervals for 2 hours after injection of the contrast medium. Contrast enhancement in these tissues was calculated in each animal for each contrast medium, and differences in enhancement were tested for significance by a growth-curve model. RESULTS: Contrast enhancement in the intervertebral disc was significantly less with gadolinium-polylysine than with gadopentetate. In muscle, no significant difference between the two media was observed. CONCLUSIONS: Molecular weight affects the diffusion of paramagnetic contrast media into the intervertebral disc. Contrast media of a high molecular weight may produce better contrast between recurrent herniated disc fragments and scar tissue than contrast media of lower molecular weight. This possibility should be rested in further studies.