ICU personnel have inaccurate perceptions of their patients' experiences.

BACKGROUND: Intensive care unit (ICU) patient care bases - among others - upon the staff's assumptions about each patient's subjective preferences and experiences. However, these assumptions may be skewed and thus result in client-professional gaps (cp-gaps), which occur in two subtypes, hyperattention and blind spots to certain burdens. cp-gaps typically reduce quality of care. We investigated whether cp-gaps of either subtype exist in a 36-bed ICU of a university hospital. METHODS: Observational study on 82 consecutive patients of a 36-bed university ICU, who voluntarily answered a psychometric questionnaire focusing on patients' experiences during an ICU stay. The questionnaire was reliable and valid (Cronbach's alpha, factor analysis). It consisted of 31 Likert-scaled items, which represented three scales of perception (communicative, intrapersonal, somatic) supplemented by 55 binary items for more specific information. Details of the questionnaire are given in the text. Demographic, educational, and medical data were registered too. Patients reported their subjective ICU experience 2-7 days after ICU discharge. Analogously, 60 staff members (physicians and nurses) reported their assumptions about patients' experiences. After correction for a general bias, group differences indicated cp-gaps. RESULTS: Twelve cp-gaps were found. Hyperattention was found in four communicative and three intrapersonal items. Blind spots appeared in two communicative, two intrapersonal, and one somatic item. The pattern of cp-gap subtypes (hyperattention/blind spots) goes well with self-attributional bias - a model of social interaction. CONCLUSIONS: cp-gaps in ICUs can be identified using analogue questionnaires for patients and staff. Both subtypes of cp-gap occur. cp-gaps are substantially influenced by self-attributional bias.

Phase I trial using weekly administration of gemcitabine and docetaxel in patients with advanced pancreatic carcinoma.

BACKGROUND: In advanced pancreatic carcinoma, no effective chemotherapy has been found yet due to the lack of appropriate response. The frequent use of gemcitabine is based on the fact that there is a significant improvement in the quality of life, but neither an effect on remission nor a detectable increase in survival rates could be observed. Therefore, the hypothesis was that the combination of gemcitabine with other drugs can result in a better outcome of patients. The aim of this study was to determine the maximally tolerable dosage of gemcitabine and docetaxel using a weekly administration regimen. PATIENTS AND METHODS: Twenty-five patients with advanced or metastatic pancreatic carcinoma received combination chemotherapy using gemcitabine and docetaxel in a weekly administration regimen, beginning with 800 mg/m2 of gemcitabine and 25 mg/m2 of docetaxel. Four patients were originally enrolled for each of the seven different dosages of both drugs. Side effects were assessed according to the WHO standard. Quality of life was evaluated according to the Core Quality of Life Questionnaire (QLQ-C30) of the European Organization for Research and Treatment of Cancer. RESULTS: Using the two maximal dosages of gemcitabine and docetaxel (gemcitabine, 800 and 1,000 mg/m2, and docetaxel, 45 and 40 mg/m2; respectively), only 3 and 2 patients were enrolled, respectively, because of toxic side effects > or = grade III according to WHO grading. Maximal dosages with tolerable side effects were 1,000 mg/m2 of gemcitabine and 35 mg/m2 of docetaxel given in weekly intervals. Main side effects of this combination chemotherapy were gastrointestinal symptoms and hematologic toxicity. CONCLUSION: Combination therapy with gemcitabine and docetaxel in advanced or metastatic pancreatic carcinoma is a well-tolerated and acceptable alternative treatment option with regard to the severity of side effects and its positive impact on quality of life and tumor-associated pain. According to the study endpoint, dosages of 1,000 mg/m2 of gemcitabine and 35 mg/m2 of docetaxel are recommended as maximum-tolerated doses (given in weekly intervals) for a future phase II trial.

Calcium regulation of gelsolin and adseverin: a natural test of the helix latch hypothesis.

The gelsolin family of actin filament binding proteins have highly homologous structures. Gelsolin and adseverin, also known as scinderin, are the most similar members of this family, with adseverin lacking a C-terminal helix found in gelsolin. This helix has been postulated to serve as a calcium-sensitive latch, keeping gelsolin inactive. To test this hypothesis, we have analyzed the kinetics of severing by gelsolin, adseverin, and a gelsolin truncate which lacks the C-terminal latch. We find that the relationship between severing rate and calcium ion concentration differs between gelsolin and adseverin, and suggest that calcium controls one rate-limiting step in the activation of adseverin and two in the activation of gelsolin. In contrast, both proteins are activated equally by protons, and have identical severing kinetics at pHs below 6.3. The temperature sensitivity of severing by adseverin and gelsolin is remarkably different, with gelsolin increasing its severing rate 8-fold per 10 degrees C increase in temperature and adseverin increasing its rate only 2-fold per 10 degrees C increase in temperature. Analysis of the gelsolin construct lacking the C-terminal helix demonstrates that this helix is responsible for the regulatory differences between gelsolin and adseverin. These results support the C-terminal latch hypothesis for the calcium ion activation of gelsolin.

Tsc2(+/-) mice develop tumors in multiple sites that express gelsolin and are influenced by genetic background.

Tuberous sclerosis (TSC) is an autosomal dominant genetic disorder in which benign hamartomas develop in multiple organs, caused by mutations in either TSC1 or TSC2. We developed a murine model of Tsc2 disease using a gene targeting approach. Tsc2-null embryos die at embryonic days 9.5-12.5 from hepatic hypoplasia. Tsc2 heterozygotes display 100% incidence of multiple bilateral renal cystadenomas, 50% incidence of liver hemangiomas, and 32% incidence of lung adenomas by 15 months of age. Progression to renal carcinoma, fatal bleeding from the liver hemangiomas, and extremity angiosarcomas all occur at a rate of less than 10%. The renal cystadenomas develop from intercalated cells of the cortical collecting duct and uniformly express gelsolin at high levels, enabling detection of early neoplastic lesions. The tumor expression pattern of the mice is influenced by genetic background, with fewer large renal cystadenomas in the outbred Black Swiss background and more angiosarcomas in 129/SvJae chimeric mice. The slow growth of the tumors in the heterozygote mice matches the limited growth potential of the great majority of TSC hamartomas, and the influence of genetic background on phenotype correlates with the marked variability in expression of TSC seen in patients.

The actin-binding proteins adseverin and gelsolin are both highly expressed but differentially localized in kidney and intestine.

To understand the distinct functions of the closely related actin-severing proteins adseverin and gelsolin, we examined the expression of these proteins in detail during mouse and human development using a new highly sensitive and specific set of antibody reagents. Immunoblot analysis demonstrated that adseverin was highly expressed in mouse kidney and intestine at all stages of development and in human fetal and adult kidney. In contrast and as reported previously, gelsolin was expressed much more widely in both murine and human tissues. Immunohistochemistry on murine kidney sections revealed a predominantly differential localization of adseverin and gelsolin. Adseverin was expressed in peripolar cells, thin limbs, thick ascending limbs, and principal cells of cortical and medullary collecting ducts where it was diffusely localized in the cytoplasm. Gelsolin was expressed in the distal convoluted tubule, intercalated cells and principal cells of cortical and medullary collecting ducts, and in ureter. In the distal convoluted tubule, gelsolin showed a diffuse distribution and in principal cells of collecting ducts a localization at the basolateral pole. In intercalated cells, gelsolin localization was heterogeneous, either at the apical pole or diffusely in the cytoplasm. In human fetal and adult kidney, adseverin was expressed only in collecting ducts whereas gelsolin was expressed in thick ascending limbs and collecting ducts. In mouse and human intestine adseverin was expressed in enterocytes with a gradient of increasing expression from the duodenum to the colon, and from the crypt to the villus. The observations indicate high level expression of adseverin in specific cells of the kidney and colon, and suggest a previously unrecognized function of adseverin in epithelial cell function.