Modeling the epidemiology and economics of directly observed therapy in Baltimore.

SETTING: From 1958 to 1978, Baltimore maintained one of the highest pulmonary tuberculosis (TB) rates in the US. But, from 1978 to 1992 its TB rate declined by 64.3% and its ranking for TB fell from second highest among large US cites to twenty-eighth. This TB trend coincided with the implementation of an aggressive directly observed therapy (DOT) program by Baltimore's Health Department. OBJECTIVES: We used modeling to estimate the range of TB cases prevented in Baltimore under DOT. Case estimates equal the difference between the observed number of TB cases in Baltimore versus the expected number if Baltimore's TB trend was replaced by the TB trend for the US (low estimate) or the TB trend for all US cities with over 250,000 residents (high estimate). Economic savings are estimated. RESULTS: Without DOT we estimate there would have been between 1,577 (53.6%) and 2,233 (75.9%) more TB cases in Baltimore, costing $18.8 million to $27.1 million. Cases prevented and expenditures saved increased with increased DOT participation. CONCLUSION: Our model predicts that Baltimore's TB decline accompanying DOT resulted in health care savings equal to twice the city's total TB control budget for this period. These results are most plausibly due to DOT, since it was the only major change in Baltimore's TB control program, and rising TB risk factors-AIDS, injection drug use, poverty-in a city where TB had been epidemic should have triggered a TB increase as in comparable US cities, rather than the observed decline. As national TB rates continue to decline it will be important to identify ways to capture and reinvest these savings to support effective TB control programs.     

Renal blood flow in pigs: changes depicted with contrast-enhanced harmonic US imaging during acute urinary obstruction.

PURPOSE: To evaluate contrast agent-enhanced harmonic ultrasonographic (US) imaging and Doppler hemodynamics during acute urinary obstruction. MATERIALS AND METHODS: In 12 piglets, the distal ureter was obstructed for 60 minutes, followed by intravenous injection of furosemide. In six piglets, ureteral pressure was further elevated to mean arterial pressure, and in six other piglets ureteral obstruction was released. Contrast-enhanced harmonic imaging was performed, and interlobar resistive index (RI) and renal blood flow were determined at baseline and during each experimental condition. A bolus injection curve was constructed by plotting mean pixel intensity versus time, and the area under this normalized curve was compared with renal blood flow values. RESULTS: Ureteral obstruction and high ureteral pressure reduced cortical renal blood flow to 88% and 66%, respectively, of baseline values. Administration of contrast agent resulted in marked homogeneous enhancement of the renal cortex. The area under the curve diminished during ureteral obstruction and correlated well with mean cortical blood flow. RI correlated well with renal perfusion pressure but poorly with changes in renal blood flow. CONCLUSION: Contrast-enhanced harmonic US imaging depicts changes in renal blood flow during acute obstruction. Interlobar RI is a good predictor of renal perfusion pressure but not of changes in renal blood flow.     

桡骨头骨折以及植入物重建后的运动学与稳定性(上)

桡骨头骨折是肘部最常见的骨折 [1].单纯桡骨头骨折为无移位骨折,若伴内侧和外侧副韧带和(或)骨间韧带损伤时,则骨折会发生移位.在更严重的损伤中,桡骨头骨折可能伴随着肘和前臂的脱位.桡骨头骨折中经常可以见到冠状突和肱骨小头骨折,这进一步削弱了肘关节的稳定性.     

Technology and health care

The invasion of technology, both in society and health care, asks for critical assessment of efficacy and safety. In a greying population hospital care will be substituted by home care in the treatment of chronic diseases. Continuity of care, between hospital and home, requires good communication between physician, patient and family. The hospital pharmacy has an essential role in providing treatment material in renal dialysis, chemotherapy or parenteral nutrition, the instruction of patients and the quality control of diagnostic tests and new devices for drug administration. The surveillance of complex medication, especially in the elderly, is an important part of that consultancy. The hospital pharmacist, in order to take up his place in the treatment team, should become familiar with new and technical aspects of drug administration in home care setting and the safety of its transfer from hospital to home.     

Wallerian degeneration after cerebral infarction: evaluation with sequential MR imaging

The dynamic signal intensity changes at magnetic resonance (MR) imaging in active and chronic wallerian degeneration in the corticospinal tract were evaluated. Forty-three patients with wallerian degeneration seen on MR images after cerebral infarction were studied. When possible, patients with acute stroke were examined with MR imaging prospectively at the onset of symptoms and then at weekly intervals for several months. Focal infarction without distal axonal degeneration is demonstrated for the 1st month following onset of clinical symptoms. At 4 weeks, a well-defined band of hypointense signal appears on T2-weighted images in the topographic distribution of the corticospinal tract. After 10-14 weeks, the signal becomes permanently hyperintense. Over several years, accompanying ipsilateral brain stem shrinkage occurs. The dark signal intensity observed on T2-weighted images between 4 and 14 weeks is believed to result primarily from transitory increased lipid-protein ratio.     

HIV and hepatitis C co-infection

HIV/HCV co-infection is emerging as a major cause of morbidity and mortality in the 21st century. This editorial reviews the prevalence of co-infection, the factors involved in acquisition of HCV, and the influence of co-infection on disease progression. We examine the results of the major co-infection trials including APRICOT, ACTG 5071 and RIBAVIC. These trials, in association with emerging evidence for future therapies currently undergoing investigation, have led to increased hope of treatment success in co-infected individuals.     

Mechanisms of initial blood pressure response to postural change

The influence of supine rest on the blood pressure response to standing and 70 degrees head-up tilt was studied in detail for the first 30 s after the change of posture. Following 20 min of supine rest, the active transition to standing was accompanied by an immediate increase in systolic pressure of 29 +/- 6 mmHg (mean +/- SEM). This was followed by large fluctuations in systolic pressure: to -28 +/- 2 mmHg below control after 7 s and to 22 +/- 2 mmHg above control after 22 s (17 mmHg in excess of the systolic pressure level after head-up tilt). Following 1 min of supine rest, there was no difference in the immediate increase in systolic pressure. However, the magnitude of the subsequent changes was significantly diminished. With head-up tilt the immediate increase in blood pressure was absent and afterwards small changes were found that were also significantly influenced by the period of prior rest. Taken in conjunction with earlier studies, the following mechanisms are suggested. The immediate blood pressure increase resulted from compression of arteries by the contracting postural muscles. The subsequent blood pressure fall was caused by at least two mechanisms: (a) the fall was predominantly of reflex origin, because the immediate pressure increase stimulated the systemic baroreceptors; (b) supine rest possibly augmented the translocation of blood from the thorax which contributed, approx. 5 s from standing, to the reflex fall of blood pressure.