Effects of lipid A and liposomes containing lipid A on platelet and fibrinogen production in rabbits

The effect of the lipid A moiety of endotoxin on platelet and fibrinogen production was studied in rabbits. Lipid A was infused intravenously in doses ranging from 1 to 100 micrograms/kg body mass; 18 hr later, selenomethionine-75Se was injected intravenously and its incorporation into fibrinogen and platelets determined. Lipid A in saline stimulated fibrinogen and platelet production, but the dose required was 50--100 times that required for an intact endotoxin. Although lipid A solubilized in triethylamine (TEA) was at least 60 times more active in the Limulus amebocyte lysate assay than was lipid A suspended in saline, the sensitivity of platelet and fibrinogen production to solubilized lipid A was increased only twofold. Incorporation of lipid A into liposomes had no effect on its Limulus activity. Lipid A in liposomes continued to stimulate platelet, but not fibrinogen, production. Leukopenia that was induced by lipid A in TEA did not occur when rabbits received the same dose of lipid A in liposomes. Lipid A, like intact endotoxin, can stimulate platelet and fibrinogen production and induce leukopenia but the doses required are high. The low solubility of lipid A in aqueous solutions may be only one factor that determines its biologic activity.     

Two-dimensional iodopeptide mapping demonstrates that erythrocyte Rh D, c, and E polypeptides are structurally homologous but nonidentical

The 32,000 molecular weight (mol wt) erythrocyte Rh D, c, and E polypeptides were separately purified from cDE/cDE erythrocytes by monoclonal immunoprecipitations and compared by two-dimensional iodopeptide mapping. Digestions of the isolated Rh polypeptides with alpha-chymotrypsin revealed a high degree of structural homology between c and E (13/14 iodopeptides were identical) and less striking homology between D and c or E (8/19 identical). The iodopeptide maps of Rh proteins purified by a nonimmunologic protocol from cDE/cDE erythrocytes were virtually identical to the composite pattern (D + c + E) deduced from the individual maps of Rh D, c, and E iodopeptides. Digestions of the isolated Rh polypeptides with trypsin revealed an overall homology of approximately 50% between iodopeptides derived from D, c, and E. These data indicate that the erythrocyte Rh D, c, and E antigens are carried by homologous but distinct molecular species; c and E appear more closely related to each other than to D.     

Cost savings with interventions to reduce aerosolized bronchodilator use in mechanically ventilated patients

Purpose

The purpose of this evaluation is to describe the cost savings associated with multimodal interventions aimed at reducing aerosolized bronchodilator use in mechanically ventilated patients without adversely affecting costs associated with length of stay (LOS).

Materials and methods

Subjects were included in the analysis if they were aged more than 18 years, on mechanical ventilation in the intensive care unit, and received aerosolized bronchodilators. Patients were excluded if they had reversible airway disease, an indication needing bronchodilator therapy. Patient data were obtained using the University Health System Consortium Clinical Data Base/Resource Manager (Chicago, IL) to compare outcomes during two 6-month periods separated by a 4-month intervention phase aimed to reduce bronchodilator use.

Results

There were no significant differences in age, sex, and LOS (observed and expected) between the preintervention and postintervention phases. Based on whole acquisition costs, the total cost of bronchodilators dispensed to the adult intensive care units over the 6-month postintervention phase was reduced by $56 960 compared with the 6-month preintervention phase ($120 562 vs $63 602, respectively).

Conclusions

Multimodal efforts to restrict aerosolized bronchodilator therapy in mechanically ventilated patients were successful and led to sustained reductions in use that was associated with substantial reductions in cost, without affecting LOS.     

Amputation for Extremity Sarcoma: Contemporary Indications and Outcomes

Introduction

Amputation for localized extremity sarcoma (ES), once the primary therapy, is now rarely performed. We reviewed our experience to determine why patients with sarcoma still undergo immediate or delayed amputation, identify differences based on amputation timing, and evaluate outcomes.

Methods

Records of patients with primary, nonmetastatic ES who underwent amputation at our institution from 2001 to 2011 were reviewed. Univariate analysis was performed, and survival outcomes were calculated.

Results

We categorized 54 patients into three cohorts: primary amputation (A1, n = 18, 33%), secondary amputation after prior limb-sparing surgery (A2, n = 22, 41%), and hand and foot sarcomas (HF, n = 14, 26%). Median age at amputation was 54 years (range 18–88 years). Common indications for amputation (> 40%) were loss of function, bone involvement, multiple compartment involvement, and large tumor size (A1); proximal location, joint involvement, neurovascular compromise, multiple compartment involvement, multifocal or fungating tumor, loss of function, and large tumor size (A2); and joint involvement and prior unplanned surgery (HF). There was no difference in disease-specific survival (DSS) (p = 0.19) or metastasis-free survival (MFS) (p = 0.31) between early (A1) and delayed (A2) amputation. Compared with cohorts A1/A2, HF patients had longer overall survival (OS) (p = 0.04).

Conclusions

Indications for amputation for extremity sarcoma vary between those who undergo primary amputation, delayed amputation, and amputation for hand or foot sarcoma. Amputations chosen judiciously are associated with excellent disease control and survival. For patients who ultimately need amputation, timing (early vs. delayed) does not affect survival.

     

Prescribing of analgesics in trauma patients.

Objective: To evaluate whether initial orders of pain medications by physicians for trauma patients were in accordance with published guidelines. Design: Concurrent, nonrandomized investigation conducted over 4 months. Materials and Methods: All adult trauma patients admitted to the intensive care unit within 12 hours of injury who stayed for at least 1 hour were eligible for study admission. Patients with injuries prohibiting accurate pain assessment (e.g., Glasgow Coma Score < 8, spinal cord injury) were excluded. Initial orders for pain medications were compared to published guidelines; correlations between dose and patient demographics were studied. Results: Of the 30 patients enrolled in the study, 83% were prescribed appropriate pain control regimens. The average dose of morphine administered during each of the 8-hour dosing intervals was approximately 12 mg. No relationship was found between patient age, sex, Glasgow Coma Score, and morphine dose; however, there was a positive correlation found between Injury Severity Score and dose. Conclusions: The majority of patients in this investigation were initially prescribed appropriate doses and intervals for pain management.     

藏药薰倒牛的活性物质研究

从植物藏药薰倒牛(BiebersteiniaheterostemonMaxim.)中首次分离得7个化合物,经化学方法和光谱解析鉴定为:β-谷甾醇(Ⅰ)、胡萝卜甙(Ⅱ)、伞形花内酯(Ⅲ)、5,7,3′-三羟基-8,4′,5′-三甲氧基黄酮(Ⅳ)、木犀草素-7-葡萄糖甙(Ⅴ)、槲皮素-7-葡萄糖甙(Ⅵ)和N-3-甲基-2-丁烯基脲(Ⅶ)。其中Ⅳ和Ⅶ是二个新的天然产物。药理实验表明化合物Ⅶ有镇痛、降压等活性。     

颅内血管支架成形术：介入前后CTA的可行性和局限性

目的：CTA对于评估颅内动脉狭窄程度和颅内支架随访是一种无创性检查。我们通过分析一组病例来评估CTA关于颅内血管支架成形术前后的动脉狭窄程度及支架随访的可行性。方法：颅内放置支架前后的8例患者接受CTA检查,一共有9个动脉狭窄并有临床症状。用CTA与传统血管造影对观察血管狭窄程度和植入支架的大小进行比较。结果：对于支架植入前的血管狭窄程度,CTA与传统血管造影比较,相差约为-15％～12％。