Potentiation of IL-2-induced t-cell proliferation by retinoids.

We evaluated the capacity of retinoids to potentiate proliferative responses of murine T-cells to recombinant human interleukin 2 (rIL-2). Concanavalin A (Con A) prestimulated spleen cells responded in a dose-dependent manner to added rIL-2. All-trans-retinoic acid (RA) at 10(-8) M potentiated the proliferative response by fivefold at saturating levels of IL-2. In similar experiments, two closely related retinamides, all-trans-(phenyl)retinamide (PR) and N-(4-hydroxyphenyl)retinamide (4-HPR), also potentiated murine splenocyte rIL-2 responses. Potentiation of IL-2-induced proliferation was dose-responsive to the concentration of added retinoid with peak potentiation occurring at 10(-10) - 10(-8) M in the presence of 10 U/ml rIL-2. Significant potentiation was observed at retinoid concentrations as low as 10(-14) M. Fluorescence flow cytometry of the responding cells revealed that among L3T4+, Lyt-2+ or total T-cells, at 72 h following Con A stimulation, essentially all of the cells expressed IL-2 receptors (IL-2R). This apparently represents near maximum IL-2R expression and treatment of the cells with retinoids did not increase IL-2R expression at that time point. The potentiation of IL-2 responses by retinoids was also observed with IL-2-dependent HT-2 cells, 98% of which were IL-2R positive. HT-2 proliferative responses to rIL-2 were potentiated as much as fourfold by 10(-10) M RA. HT-2 proliferative responses to rIL-2 were potentiated by all three retinoids dose dependently. Significant potentiation was observed with as little as 10(-14) M retinoid. Retinoids in the absence of IL-2 induced no proliferative responses. These data suggest that retinoids can augment the capacity of IL-2 to induce T-cell proliferation using Con A-activated murine splenic T-cell blasts and a long-term-cultured T-cell line.     

Caterpillar envenomations: a prospective study of 112 cases

A 1-year prospective study was conducted to identify epidemiological factors associated with caterpillar envenomations. Of 117 envenomations, 112 were included in the study. Identification of the caterpillars involved was accomplished in 68% of the cases. Six caterpillar species were identified, 4 of which [Hemileuca maia (Drury), Automeris io (F), Megalopyge opercularis (JE Smith)/Lagoa crispata (Packard) and Sibine stimulea (Clemens)] were properly implicated in envenomations. Clinical effects most commonly reported were local pain, erythema and swelling in 96%, 89% and 72% of patients, respectively. Atypical responses including muscle spasms, paresthesia and radiating pain to an extremity were noted in 26% of patients. Sixteen percent of patients had a history of allergy, but no patient in this subgroup exhibited a "hive-like" dermatologic or anaphylactic allergic response. No positive correlation could be drawn between allergy history and extent of clinical effect following envenomation. Mild to moderate local response following envenomation was typical. However, 61% of patients evaluated experienced mild to moderate effects at least 24 h post-envenomation.     

Plant nurseries: a reliable resource for plant identification?

Poison Centers frequently rely on the assistance of local plant nurseries to identify unknown plants involved in exposures. The reliability and accuracy of utilizing this method has never been studied; therefore, our objective was to evaluate this primary resource of plant identification. A study was done in which callers were instructed to take plant samples to a local nursery for visual identification. Once the patient was treated according to our normal protocol, the plant specimen was sent to a botanist for a second identification. The botanist provided his identification results through a blinded process. The collected data was gathered from 68 cases that completed the necessary study criteria. In 58% of the cases, plant nurseries were an unreliable source for plant identification. These incorrect identifications resulted in the "undertreatment" in 24% of the exposures.     

白蛋白微球作为肝靶向给药载体的研究

用均匀设计方法和计算机技术筛选了乳化化学交联法制备白蛋白微球的六个因素,十二个水平。优化出最佳制备工艺,制备了平均粒径0.41～0.47μm的白蛋白微球。将此工艺制备的¹²⁵I-白蛋白微球做动物体内研究,结果表明微球iv后主要浓集在肝脏,可达注入总剂量的68%,此微球在靶组织肝脏的变化规律可用二室模型契合。     

Cabbage seed protease inhibitor: a slow, tight-binding inhibitor of trypsin with activity toward thrombin, activated Stuart factor (factor Xa), activated Hageman factor (factor XIIa), and plasmin

An inhibitor of procoagulant and fibrinolytic enzymes was derived from cabbage seeds by a procedure using acetone precipitation, ion-exchange chromatography, and gel filtration. The cabbage seed inhibitor was a 10-Kd monomeric protein with intrachain disulfide bonds. This preparation prevented clot formation in whole blood and blocked the ability of thrombin to induce clot formation in plasma and to induce platelet aggregation. A number of proteases were inhibited, as demonstrated by using purified enzymes in amidolytic assays. Tight-binding inhibition was observed for activated Stuart factor (factor Xa) and plasmin. Inhibition of thrombin and activated Hageman factor (factor XIIa) was observed with a molar excess of inhibitor. No inhibition was detected for activated plasma thromboplastin antecedent (factor XIa), plasma kallikrein, or C1 esterase. Reaction progress curves for trypsin indicated slow, tight-binding inhibition, with an apparent inhibition constant in the nanomolar range or less. The electrophoretic mobility of trypsin was altered by the inhibitor in nondenaturing polyacrylamide gel electrophoresis (PAGE) but not in sodium dodecyl sulfate (SDS)-PAGE, indicating noncovalent bonding. Only partial reversal of trypsin inhibition could be demonstrated by washing the inhibitor from enzyme immobilized on solid beads. A dot-blot technique with cabbage seed inhibitor was capable of detecting 10 ng nitrocellulose-bound trypsin. The dot-blot technique also appeared capable of detecting plasmin. These findings demonstrated the potential utility of this inhibitor as a probe for detection of tightly bound proteases. In summary, cabbage seed extracts contain an inhibitor with activity toward a broad range of proteases important to hemostasis. To our knowledge, this agent represents the first inhibitor isolated from a plant source that inhibits thrombin.     

Purification of Hageman factor (factor XII) on columns of popcorn- agarose

Purification of Hageman factor (HF, factor XII) from human plasma is a tedious procedure and the product is not always in the precursor form. Hojima has described a protein derived from corn kernels that inhibits the enzymatic properties of HF. This inhibitor binds to the precursor form of HF. Rapid purification of HF was achieved by using as the major purification step adsorption of this clotting factor to popcorn inhibitor bound to agarose. The product had a specific activity of 50.0 to 67.1 coagulant units of HF per milligram protein, and the yield was 33% to 40% of the HF content of the starting plasma. The purified protein displayed a single band upon unreduced or reduced sodium dodecyl sulfate polyacrylamide gel electrophoresis and less than 0.1% was in an activated form, as measured in coagulant assays. The technique described is more rapid and reliable than methods described earlier.     

Induction of expression of monocyte interleukin 1 by Hageman factor (factor XII).

The results reported here indicate that activated species of Hageman factor (HF, factor XII), a protein that mediates blood clotting, fibrinolysis, and activation of the complement cascade, induce elaboration of interleukin 1 (IL-1) by human monocytes. Augmentation of IL-1 production in mononuclear cell cultures was observed when HF was present along with lipopolysaccharide (LPS) but was not observed with HF alone. Furthermore, antiserum to HF abrogated the enhancement of IL-1 in cultures containing HF and LPS. Total IL-1 activity, which represents secreted and cell-associated IL-1, was enhanced in LPS-stimulated mononuclear cultures by HF. In the absence of LPS, the initial activation product of HF, HFa, which contains the serine protease enzyme activity and the surface-binding domains of the protein, induced IL-1 beta protein and mRNA. In the presence of LPS, the enzymatic moiety (HFf), which is also contained in HF and HFa, amplified IL-1 production. Induction and amplification of monocyte IL-1 by HF provides further evidence for establishing a role for HF in the acute-phase reaction and the cellular immune response.     

Representation of spatial frequency and orientation in the visual cortex

Knowledge of the response of the primary visual cortex to the various spatial frequencies and orientations in the visual scene should help us understand the principles by which the brain recognizes patterns. Current information about the cortical layout of spatial frequency response is still incomplete because of difficulties in recording and interpreting adequate data. Here, we report results from a study of the cat primary visual cortex in which we employed a new image-analysis method that allows improved separation of signal from noise and that we used to examine the neurooptical response of the primary visual cortex to drifting sine gratings over a range of orientations and spatial frequencies. We found that (i) the optical responses to all orientations and spatial frequencies were well approximated by weighted sums of only two pairs of basis pictures, one pair for orientation and a different pair for spatial frequency; (ii) the weightings of the two pictures in each pair were approximately in quadrature (1/4 cycle apart); and (iii) our spatial frequency data revealed a cortical map that continuously assigns different optimal spatial frequency responses to different cortical locations over the entire spatial frequency range.     

EHR Adoption and Hospital Performance: Time‐Related Effects

Objective

To assess whether, 5 years into the HITECH programs, national data reflect a consistent relationship between EHR adoption and hospital outcomes across three important dimensions of hospital performance.

Data Sources/Study Setting

Secondary data from the American Hospital Association and CMS (Hospital Compare and EHR Incentive Programs) for nonfederal, acute‐care hospitals (2009–2012).

Study Design

We examined the relationship between EHR adoption and three hospital outcomes (process adherence, patient satisfaction, efficiency) using ordinary least squares models with hospital fixed effects. Time‐related effects were assessed through comparing the impact of EHR adoption pre (2008/2009) versus post (2010/2011) meaningful use and by meaningful use attestation cohort (2011, 2012, 2013, Never). We used a continuous measure of hospital EHR adoption based on the proportion of electronic functions implemented.

Data Collection/Extraction Methods

We created a panel dataset with hospital‐year observations.

Principal Findings

Higher levels of EHR adoption were associated with better performance on process adherence (0.147; p < .001) and patient satisfaction (0.118; p < .001), but not efficiency (0.01; p = .78). For all three outcomes, there was a stronger, positive relationship between EHR adoption and performance in 2010/2011 compared to 2008/2009. We found mixed results based on meaningful use attestation cohort.

Conclusions

Performance gains associated with EHR adoption are apparent in more recent years. The large national investment in EHRs appears to be delivering more consistent benefits than indicated by earlier national studies.     

Chronic Albumin Infusions to Achieve Diuresis in Patients with Ascites Who Are Not Candidates for Transjugular Intrahepatic Portosystemic Shunt (TIPS)

While transjugular intrahepatic portosystemic shunt (TIPS) is a common therapy for cirrhotic patients with diuretic-resistant or diuretic-refractory ascites, some patients are unsuitable for the procedure for technical or medical reasons. We report our experience with the use of chronic intravenous albumin infusions to achieve diuresis in this difficult patient population and review the historic experience of chronic albumin infusions as a treatment for ascites. Nineteen patients with cirrhosis and diuretic-resistant or diuretic-refractory ascites who were deemed unsuitable for TIPS received outpatient intravenous albumin infusions (50 g) weekly for at least 4 weeks. The following endpoints were retrospectively recorded: serum sodium, serum creatinine, blood urea nitrogen, hematocrit, bilirubin, albumin, international normalized ratio, body weight, and Model for End-stage Liver Disease (MELD) score. The contraindicatoins for TIPS included the following: portal vein thrombosis, two; advanced age, one; encephalopathy, nine; hyperbilirubinemia, five; and other, two. Compared to pretreatment, posttreatment weight decreased in 17 patients, remained unchanged in 0 patients, and increased in 2 patients. The overall mean change in body weight (before vs. after therapy) was 8 lb (P < 0.05). The only significant change in biochemistries was an increase in serum albumin from 2.5 g/dl before therapy to 3.5 g/dl after therapy (P < 0.05). We conclude that (1) recurrent intravenous weekly albumin infusions resulted in significant loss of edema and ascites as measured by loss of body weight, and (2) clinicians may want to consider chronic albumin infusions for selected patients with refractory ascites who are not candidates for TIPS.