Study of the localization of radiopacities similar to calcified carotid atheroma by means of panoramic radiography.

OBJECTIVE: To determine the location in soft tissues of the calcifications, similar to calcified carotid atheromas, that can be observed radiographically in the cervical region in panoramic radiographs. STUDY DESIGN: In each anatomic cadaver specimen preserved in formol, consisting of the head and neck, radiopaque spheres (made from gutta-percha) were positioned in anatomic structures of the cervical region that can be sites of calcification. For each anatomic structure marked in this way, panoramic radiography was performed, consisting of 17 radiographs. The images obtained were analyzed by 24 examiners who indicated which radiographs, in their opinion, presented the radiopaque reference projected in the region of bifurcation of the carotid artery. Analysis of 2 proportions from agreement and disagreement was used to determine radiopacities that could be confused in panoramic radiographs with calcified atheromas in the carotid artery. RESULTS: The results showed that 75% (18) of the examiners correctly indicated the reference in the bifurcation of the carotid artery and 79.2% (19) indicated a triticeous cartilage as calcified atheroma of the carotid artery. CONCLUSIONS: Calcified atheromas of the carotid artery are not the only features that can produce radiopaque images lateral to the panoramic radiograph; the presence of calcification in the triticeous cartilage also can induce an erroneous diagnosis of calcified carotid atheroma.     

Synthesis and hypoglycemic activity of substituted 8-(1-piperazinyl)imidazo[1,2-a]pyrazines.

A series of alkyl- and halo-substituted 8-(1-piperazinyl)imidazo[1,2-a]pyrazines were prepared using two approaches, the condensation of alpha-halocarbonyl derivatives with an aminopyrazine or the oxidation-dehydration of a [(beta-hydroxyalkyl)amino]pyrazine. These imidazo[1,2-a]pyrazines were evaluated for their binding affinity to the alpha 1, alpha 2, beta 1, and beta 2 adrenergic receptors as well as their ability to lower blood glucose in insulin resistant hyperglycemic ob/ob mice. Modifications on 8-(1-piperazinyl)imidazo[1,2-a]pyrazine (4) reduced alpha 2 binding, lowered hypoglycemic potency, and showed variations in binding to the alpha 1, beta 1, and beta 2 adrenergic receptors. In addition to 4, the 2-methyl, 3-methyl, and 5-methyl 8-(1-piperazinyl)imidazo[1,2-a]pyrazines (16k, 25m, and 16f, respectively) displayed high affinity for the alpha 2 receptor and were potent hypoglycemic agents when compared to 2-amino-7,8-dihydro-4-(1-piperazinyl)-6H-thiopyrano[3,2- d]pyrimidine (MTP-1403, 2). Receptor binding was modified by use of a 4-methylpiperazine moiety which reduced alpha 1 and beta 1 binding while retaining some hypoglycemic activity. The structure-activity relationship for heterocyclic alkyl and halo substitution on biological activity is discussed.     

Persistence of Mammary Artery Branches and Blood Supply to the Left Anterior Descending Artery

Background. Partial harvesting of the left internal mammary artery (LIMA) is a widespread technique used during minimally invasive coronary operations performed through a left anterior small thoracotomy. The influence of persisting LIMA branches was investigated to evaluate their effect on the blood flow of the left anterior descending artery.

Methods. Thirty patients, 15 with totally (group A) and 15 with partially (group B) harvested LIMAs, were evaluated. All the patients underwent postoperative angiography, during which a flow map of the LIMA was performed. The average peak velocity and the diastolic-to-systolic peak velocity ratio were recorded. The LIMA graft flow pattern was recorded in the proximal and distal thirds of the artery. Intramammary adenosine (12 to 14 μg) was injected and the average peak velocities before and after injection were calculated.

Results. The average peak velocity was similar in both groups in the proximal and distal thirds of the LIMA (25 ± 7 and 26 ± 5 cm/sec, respectively, in group A versus 27 ± 5 and 25 ± 5 cm/sec, respectively in group B; p = NS). The diastolic-to-systolic peak velocity ratio was similar proximally (0.78 ± 0.3 in group A versus 0.69 ± 0.3 cm/s in group B; p = NS), but not distally (1.72 ± 0.1 in group A versus 0.97 ± 0.3 in group B; p < 0.0005). The LIMA graft flow reserve was similar both proximally and distally (2.6 ± 0.6 and 2.5 ± 0.3 cm/s, respectively, in group A versus 2.6 ± 0.5 and 2.6 ± 0.3 cm/s, respectively, in group B; p = NS).

Conclusions. The persistence of LIMA branches does not influence the blood flow of the left anterior descending artery after acute adenosine-induced myocardial hyperemia. If a left anterior small thoracotomy is used in left anterior descending artery direct revascularization, complete LIMA harvesting is not mandatory and depends on the personal preference of the surgeon.     

Suppression of sleepiness in drivers: Combination of caffeine with a short nap

Previous research has shown that caffeine and a<15-min nap effectively and separately reduce sleepiness in drivers for I hr. In the present study, we examined in 12 sleepy individuals the treatments combined, taken during a 30-min break, prior to a longer (2 hr) continuous monotonous afternoon drive in a car simulator. Nonnap comparisons were 200 mg caffeine only and placebo. For placebo, driving incidents. Subjective and electroencephalographic measures of sleepiness all reflected a mid-afternoon peak'. This peak was significantly reduced by caffeine and eliminated by the combined treatment, which reduced incidents to 9% of placebo levels versus 34% of placebo levels for caffeine alone. Naps comprising “nonsleep dozing” were still effective.     

Reduced activity of the red-cell sodium-potassium pump in human obesity

Looking for evidence of reduced energy use in the cells of obese persons, we measured the numbers of sodium-potassium-pump units in erythrocytes from a group of 21 obese human subjects and found them to be reduced by 22 per cent as compared with those of nonobese controls (P <0.001). The cation-transport activity of the pump, as measured by 86rubidium uptake by the cells, we also reduced in parallel with decrease in pump units. An increased concentration of sodium in the red cells of obese subjectes was also found (9.6 +/- 0.7 vs. 7.1 +/- 0.6 mmol per liter of cells; P<0.01). This finding demonstrates independently the physiologic importance of reduced numbers of sodium-pump units and reduced pump activity as measured by ouabain binding and rubidium transport, respectively. The magnitude of the reduction in the number of pump units was found to be negatively correlated with the percentage of ideal body weight (r = 0.56, P<0.001); this observation suggests a possible role of abnormalities of the sodium pump in the pathophysiology of obesity.     

Evidence for a subgroup of essential hypertensives with non-suppressible excretion of aldosterone during sodium loading

Summary In patients with grade I and II essential hypertension studied during sodium loading (Na⁺ excretion above 175 meq·d^–1) we found a bimodal behaviour of aldosterone excretion and could distinguish two groups of patients: In the major part of essential hypertensives sodium loading led to a suppression of aldosterone excretion below 6 µg·d^–1, which is the highest control value during sodium loading, with an average of 2.7±1.4 (SD) µg·d^–1. Aldosterone excretion in a second group of patients was not suppressible below 6 µg·d^–1 despite forced sodium loading; it resulted in an average value of 10.0±3.0 (SD) µg·d^–1. During sodium deprivation or free sodium intake, aldosterone excretion in the first group of patients followed exactly the behaviour of normotensive controls, while in the second group of essential hypertensives the correlation of aldosterone excretion and log. Na excretion or log. Na⁺/K⁺ ratio in 24 h urine (r=–0.59) was far below the control value ofr=–0.87. Serum potassium concentration during sodium loading was significantly (p<0.001) lower (3.81±0.44 meq·l^–1) in the essential hypertensives with non-suppressible aldosterone excretion compared to those with suppressible aldosterone excretion (4.26±0.37 meq·l^–1). The blood pressure response to treatment with 200 mg spironolactone·d^–1 was better (p<0.05) in patients with non-suppressible aldosterone excretion compared to the essential hypertensives with normal aldosterone regulation. The plasma renin activity of both groups of patients was not significantly different, however, a tendency prevailed towards lower PRA-values in the patient group with non-suppressible aldosterone excretion during sodium loading.With the technical help of Mrs. R. Schendschilorz and Mrs. G. Suckau     

Accuracy of Preoperative Templating in Total Hip Arthroplasty With Special Focus on Stem Morphology: A Randomized Comparison Between Common Digital and Three-Dimensional Planning Using Biplanar Radiographs

BackgroundAccurate preoperative planning is a key component of successful total hip arthroplasty (THA). The purpose of the present study was to compare the accuracy and reliability of three-dimensional (hipEOS) and common digital two-dimensional (TraumaCad) templating with special focus on stem morphology.Methods51 patients undergoing THA were randomized to two groups. Preoperative planning was performed on 23 patients with hipEOS (3D) and on 28 patients with TraumaCad (2D) planning software. Planning results were compared with the implanted component size. Inter- and intraobserver reliability as well as planning accuracy of both planning methods with special focus on straight and short stem design were recorded.ResultsIntraobserver reliability of both planning methods was good for component planning (ICC_2,1: 0.835-0.967). Interobserver ICC_2,1 for stem and cup planning were higher for 3D templating (3D ICC_2,1: 0.906-0.918 vs. 2D ICC_2,1: 0.835-0.843). Total stem and cup size predictions were within 2 sizes for 3D and within 3 sizes for 2D planning. Comparing short stem planning accuracy of both planning methods, absolute difference between implanted and planned component size was significantly lower in 3D planning (P = .029). There was no significant difference in straight stem (P = .935) and cup (P = .954) planning accuracy.ConclusionOur findings suggest that 3D templating with hipEOS software has a good overall reliability and may have a better planning accuracy of short stem prostheses than digital templating with TraumaCad software. Assuming that the number of implanted short stem prostheses will further increase in coming years, a more precise planning with 3D technique can contribute to improve surgery outcome.     

The awesome Asthma School Days Program: educating children, inspiring a community

Program planners developed an educational program to improve the health of children with asthma in grades three to five in Milwaukee (Wis.) Public Schools. During 1997-1998, 1,400 students from 74 elementary schools participated in the Awesome Asthma School Days education program. In a cross-sectional survey, about 40% of children reported play interrupted and sleep disturbed by asthma, more than 50% of children reported exposure to smoke in their home, most children lacked asthma self-care tools, and most children with persistent symptoms did not use an anti-inflammatory inhaler. The educational program improved students' expectations about normal play and sleep and improved their understanding of asthma. Leaders in Milwaukee used the survey results to develop a community action plan. The educational program, surveys, community partnerships, and strategic plans can be replicated in other schools.