Chemotactic factors and renal inflammation

The mechanisms of leukocyte entry into the kidney during inflammatory renal disease have recently received considerable attention. Chemotactic factors appear to play a central role in this process, not only by inducing leukocyte movement but also by enhancing endothelial and leukocyte adhesiveness and endothelial permeability. The evidence supporting the role of chemotactic factors in renal inflammation comes from three types of studies. (1) Cell culture studies have shown that renal parenchymal cells produce chemotactic factors in response to proinflammatory stimuli. (2) Immunohistochemical and in situ hybridization analyses of renal tissue from patients or experimental animals have demonstrated local renal expression of chemotactic factors in association with inflammatory disease. (3) Experiments designed to neutralize the chemoattractant activity of specific chemotactic factors in leukocyte-dependent models of renal injury have shown an attenuation of inflammatory infiltrates and a decrease in indices of renal damage. In this article, these data are reviewed for complement-derived chemotactic factors, the leukocyte-specific chemokines, and the interstitial chemoattractant osteopontin, and the possibilities of therapeutic interventions based on abrogating chemoattractant expression or function in human renal disease are considered.     

赛庚啶对离体犬心肌肌质网Ca2+,Mg2+—ATP酶活性和45Ca2+摄取功能的影响

当赛庚啶浓度在8×10^-6mol/L～2×10^-4mol/L之间时,该药对正常犬心肌肌质网Ca²⁺,Mg²⁺—ATP酶活性几乎没有影响,仅在10^-3mol/L时对该酶活性才有一定的抑制作用(抑制率为39.85%,P<0.01)。正常犬心肌肌质网的⁴⁵Ca²⁺摄取过程有明显的时间依赖性,至第30 min,其⁴⁵Ca²⁺摄取量可达312.79±22.25 nmol/mg protein.赛庚啶对心肌肌质网的~(45)Ca²⁺摄取有一定的抑制作用,其IC₅₀为1.94×10^-4mol/L。     

Simon nitinol inferior vena cava filter: initial clinical experience. Work in progress

The Simon nitinol filter for percutaneous interruption of the vena cava to prevent pulmonary embolism is currently undergoing a multicenter clinical trial. Preliminary clinical results are reported as work in progress. The results in 44 patients at two centers are analyzed in detail, and major events are reported from 103 patients in 17 centers in the United States during a 10-month period. The filter was successfully inserted via the femoral or jugular route in all patients through a 9-F catheter. The placement procedure was easy and without significant complications. Follow-up studies included plain radiography, ultrasonography, magnetic resonance (MR) imaging, and clinical evaluation. No filter migration or perforation occurred among the 103 patients. Symptomatic occlusions occurred in 7%-9%, comparable to other series, and some asymptomatic occlusions were detected with MR imaging only. The implications of occlusion of the filter are discussed.     

Absorbed dose to the fetus during bone scintigraphy

The authors observed the uptake of radiopharmaceutical and calculated absorbed dose in fetuses of two patients who underwent bone scintigraphy with technetium-99m methylene diphosphonate. Dose estimates per administered activity were 17 mrad/mCi (4.6 microGy/MBq) for an 8-week-old fetus and 9.7 mrad/mCi (2.6 microGy/MBq) for an 18-week-old fetus. Neither fetus demonstrated radionuclide uptake above maternal background levels. The uterine activity showed rapid clearance, with an effective half-life of 12 minutes after reaching a maximum within 1 minute after injection. Major contribution to fetal dose comes from the presence of the radionuclide in the maternal bladder. The authors conclude that bone scintigraphy performed unknowingly in pregnant individuals presents negligible increased risk to the fetus.