Citations

Fluorescence spectroscopic studies are powerful tools for the evaluation of receptor structure and the dynamic changes associated with receptor activation. Here, we have developed two chemically distinct fluorescent probes of the cholecystokinin (CCK) receptor by attaching acrylodan or a nitrobenzoxadiazole moiety to the amino terminus of a partial agonist CCK analogue. These two probes were able to bind to the CCK receptor specifically and with high affinity, and were able to elicit only submaximal intracellular calcium responses typical of partial agonists. The fluorescence characteristics of these probes were compared with those previously reported for structurally-related full agonist and antagonist probes. Like the previous probes, the partial agonist probes exhibited longer fluorescence lifetimes and increased anisotropy when bound to the receptor than when free in solution. The receptor-bound probes were not easily quenched by potassium iodide, suggesting that the fluorophores were protected from the extracellular aqueous milieu. The fluorescence characteristics of the partial agonist probes were quite similar to those of the analogous full agonist probes and quite distinct from the analogous antagonist probes. These data suggest that the partially activated conformational state of this receptor is more closely related to its fully active state than to its inactive state.

Abstract Human long DNA in stool may reflect nonapoptotic exfoliation and has been used as a colorectal cancer (CRC) marker. Targeting human-specific Alu repeats represents a logical but untested approach. A real-time Alu PCR assay was developed for quantifying long human DNA in stool and evaluated in this study. The accuracy and reproducibility of this assay and the stability of long DNA during room temperature fecal storage were assessed using selected patient stools and stools added to human DNA. Thereafter, long DNA levels were determined in blinded fashion from 18 CRC patients and 20 colonoscopically normal controls. Reproducibility of real-time Alu PCR for quantifying fecal long DNA was high (r2 = 0.99; P < 0.01). Long DNA levels in nonbuffered stools stored at room temperature fell a median of 75% by 1 day and 81% by 3 days. An EDTA buffer preserved DNA integrity during such storage. Human long DNA was quantifiable in all stools but was significantly higher in stools from CRC patients than from normal controls (P < 0.05). At a specificity of 100%, the sensitivity of long DNA for CRC was 44%. Results indicate that real-time Alu PCR is a simple method to sensitively quantify long human DNA in stool. This study shows that not all CRCs are associated with increased fecal levels of long DNA. Long DNA degrades with fecal storage, and measures to stabilize this analyte must be considered for optimal use of this marker. (Cancer Epidemiol Biomarkers Prev 2006;15(6):1115–9)

The biological changes that occur in the brains of Alzheimer's disease (AD) patients are thought to begin long before the onset of clinical symptoms. Although current therapeutic agents have been approved only for patients with mild to moderate AD, Alzheimer‐type pathology in patients with mild to moderate AD is already quite advanced. One impetus for the development of the concept of mild cognitive impairment (MCI) was the attempt to recognize AD early in its clinical expression and to determine whether it is possible through therapeutic interventions to improve the memory impairment at this stage or delay further progression to dementia. To this end, several clinical trials have been conducted in patients with MCI. On September 8 and 9, 2004 a meeting of the Alzheimer's Association Research Roundtable was held at which experts in the field of MCI convened to review the collective experience from these trials and to consider potential approaches that might improve MCI clinical trials in the future. This article summarizes the presentations and discussions of that meeting.

There are many who feel that the achievement of a disease‐modifying (DM) designation for a drug is an important goal in Alzheimer disease (AD) therapeutics. Several designs that might prove DM have been proposed, including randomized start, randomized withdrawal, and slope analysis. Using biomarkers such as cerebrospinal fluid assays or imaging features as primary outcome measures have also been considered a way of proving DM. The available methods for establishing DM are fraught with logistical and analytic problems. Unless the drug's benefits are large, attempts to prove DM for a truly effective drug may fail. Therefore, clinical trial designs that are the simplest to conduct and interpret are superior to those more complex approaches intended to prove DM.

AbstractWe explore the controversial issue of the role of eosinophils in host defense against helminthic parasites using the established Schistosoma mansoni infection model in 2 novel mouse models of eosinophil lineage ablation (ΔdblGATA and TgPHIL). No eosinophils were detected in bone marrow of infected ΔdblGATA or TgPHIL mice, despite the fact that serum IL-5 levels in these infected mice exceeded those in infected wild type by approximately 4-fold. Liver granulomata from infected ΔdblGATA and TgPHIL mice were likewise depleted of eosinophils compared with those from their respective wild types. No eosinophil-dependent differences in granuloma number, size, or fibrosis were detected at weeks 8 or 12 of infection, and differential accumulation of mast cells was observed among the ΔdblGATA mice only at week 12. Likewise, serum levels of liver transaminases, alanine aminotransferase (ALT), and aspartate aminotransferase (AST) increased in all mice in response to S mansoni infection, with no eosinophil-dependent differences in hepatocellular damage observed. Finally, eosinophil ablation had no effect on worm burden or on egg deposition. Overall, our data indicate that eosinophil ablation has no impact on traditional measures of disease in the S mansoni infection model in mice. However, eosinophils may have unexplored immunomodulatory contributions to this disease process.

Purpose The purpose of this study was to assess the feasibility of a nurse-driven effort to improve hyperglycemia management in the intensive care unit (ICU) setting. Methods The setting was the ICU of a large urban hospital. The program was composed of 3 components: nurses as leaders, a clinical pathway to identify patients in need of hyperglycemia therapy, and implementation of a redesigned insulin infusion algorithm (the Columnar Insulin Dosing Chart). Time to reach a target glucose range of 80 to 110 mg/dL (4.4-6.1 mmol/L) was evaluated. Results One hundred sixteen ICU nurses were trained in the project. The Columnar Insulin Dosing Chart was applied to 20 patients. The average time required to reach the target blood glucose range was 12.8 hours. Below-target blood glucose levels were 6.9% of all blood glucose levels recorded, but only 0.9% were below 60 mg/dL (3.3 mmol/L). There was no sustained hypoglycemia, and no persistent clinical findings attributable to hypoglycemia were noted. Barriers to implementing the project included an increased nursing workload, the need for more finger-stick blood glucose monitors, and the need to acquire new finger-lancing devices that allowed for shallower skin puncture and increased patient comfort. Conclusions Tighter glycemic control goals can be attained in a busy ICU by a nurse-led team using a pathway for identifying and treating hyperglycemia, clear decision support tools, and adequate nurse education. The novel chart based insulin infusion algorithm chosen as the standard for this pilot was an effective tool for reducing the blood glucose to target range with no clinically significant hypoglycemia.