Assessment of two hand hygiene regimens for intensive care unit personnel

OBJECTIVE

To compare skin condition and skin microbiology among intensive care unit personnel using one of two randomly assigned hand hygiene regimens: a 2% chlorhexidine gluconate (CHG)-containing traditional antiseptic wash and a waterless handrub containing 61% ethanol with emollients (ALC).

DESIGN

Prospective, randomized clinical trial.

SETTING

Two critical care units (medical and surgical) in a large, metropolitan academic health center in Manhattan.

SUBJECTS

Fifty staff members (physicians, nurses, housekeepers, respiratory therapists) working full time in the intensive care unit.

INTERVENTIONS

One of two hand hygiene regimens randomly assigned for four consecutive weeks.

MEASUREMENTS AND MAIN RESULTS

The two outcomes were skin condition (measured by two tools: Hand Skin Assessment form and Visual Skin Scaling form) and skin microbiology. Samples were obtained at baseline, on day 1, and at the end of wks 2 and 4. Participants in the ALC group had significant improvements in the Hand Skin Assessment scores at wk 4 (p = 0.04) and in Visual Skin Scaling scores at wks 3 (p = 0.01) and 4 (p = 0.0005). There were no significant differences in numbers of colony-forming units between participants in the CHG or ALC group at any time period. The ALC regimen required significantly less time than the CHG regimen (mean: 12.7 secs and 21.1 secs, respectively; p = 0.000) and resulted in a 50% reduction in material costs.

CONCLUSIONS

Changes in hand hygiene practices in acute care settings from the traditional antiseptic wash to use of plain, mild soap and an alcohol-based product should be considered. Further research is needed to examine the association between use of antiseptic products for hand hygiene of staff and reductions in nosocomial infection rates among patients.

Growth arrest in A549 cells during hyperoxic stress is associated with decreased cyclin B1 and increased p21(Waf1/Cip1/Sdi1) levels

Exposure to high concentrations of oxygen has previously been shown to cause growth arrest in A549 cells, a distal lung epithelial cell line. We found that when A549 cells were exposed to 95% oxygen they underwent substantial growth inhibition. This was associated with induction of p21(Waf1/Cip1/Sdi1) protein and a decrease in cyclin B1 protein. Flow cytometry revealed that A549 cells exposed to hyperoxia had a significant decrease in the percentage of cells in G(1) and a modest but significant increase in the percentage of cells in S phase and G(2)/M, consistent with cells entering S phase. A549 cells in room air and hyperoxia were then treated with nocodazole, a mitotic inhibitor. Room air A549 cells treated with nocodazole showed a marked increase in G(2)/M consistent with mitotic arrest. In contrast, hyperoxic treated cells had a modest but significant decrease in G(1) but only a minimal increase in G(2)/M consistent with partial G(1)/S arrest and growth inhibition in S phase. To further investigate the role of p21(Waf1/Cip1/Sdi1) as a checkpoint regulator during hyperoxic growth inhibition, HCT116 cells with wild-type and null p21(Waf1/Cip1/Sdi1) were exposed to hyperoxia. Both wild-type p21(+/+) cells and null p21(-/-) cells underwent growth inhibition when exposed to hyperoxia. At 48 h the hyperoxic treated HCT116 p21(+/+) had a similar cell cycle distribution as the hyperoxic treated HCT116 p21(-/-) cells, suggesting that p21(Waf1/Cip1/Sdi1) may not be essential for growth arrest during hyperoxia. These findings suggest that hyperoxia causes partial growth arrest at different phases of the cell cycle but primarily in S phase, that hyperoxic growth arrest is associated with a decrease in cyclin B1 protein and that p21 induction may not be essential for hyperoxic growth arrest.

Radiological-pathological correlation: alveolar pattern

This review summarizes important pathological lesions of the lung that typically present radiographically with an 'alveolar pattern'. For each entity, the latest findings as to its pathogenesis, aetiology and pathology are reviewed in the introductory remarks. We then present the typical radiological appearances alongside macroscopic and microscopic pathological photographs. It is hoped that the parallel presentation of radiological image with the pathology will enhance the understanding of the diverse range of diseases the aevolar pattern comprises.

Increased level of HSP27 but not of HSP72 in human heart allografts in relation to acute rejection

BACKGROUND

Increased expression of heat shock proteins (HSPs) was assumed during cardiac allograft rejection. To find evidence for this in man, we quantified HSP27 and HSP72 in cardiac allograft biopsies.

METHODS

In parallel to histological assessment of rejection, HSP27 was quantified by Western blotting in a total of 43 biopsies sampled from 3 patients. HSP72 was analyzed in parallel in 30 of the 43 cases. For comparison, HSPs were analyzed in myocardium.

RESULTS

HSP27 was significantly higher in rejecting cardiac allografts than in non-rejecting allografts and non-failing myocardium (1.52 +/- 0.25 vs. 0.83 +/- 0.11 vs. 0.50 +/- 0.05 microg/mg protein). Similarity for HSP72 (6.27 +/- 1.54 vs. 4.06 +/- 1.03 vs. 6.27 +/- 0.76 microg/mg protein) was not found.

CONCLUSION

For the first time in humans with cardiac allograft rejection, increased expression of HSP27, which could be important for cardiac self-protection, was demonstrated. For the lack of increased HSP72 expression, the influence of the cyclosporine A treatment was discussed.

Biopsy diagnosis of malignant versus benign liver "nodules": new helpful markers. An update

Improved imaging techniques have led to an increased detection of suspicious "nodules" in the cirrhotic and noncirrhotic liver. Although the histologic diagnosis of clearly benign or clearly malignant lesions is usually straightforward, problems arise in the differential diagnosis of benign "nodules" and dysplastic lesions or well-differentiated hepatocellular carcinomas. This is especially so in limited diagnostic material, such as cytologic preparations from fine-needle aspirates and needle-core tissue biopsies. Recently, additional helpful markers have been described that may help to establish a conclusive diagnosis even on such material. Two of these, the reticulin stain and immunohistochemical staining for CD34, have been found to be useful also in cytologic cellblock material. Telomerase, a complex enzyme that is active in most malignant tumors, has also been found to show strong activity in most hepatocellular carcinomas. Mention is made of an immunohistochemical marker (MOC-31), reported to be useful in the differentiation between metastatic adenocarcinoma and hepatocellular carcinoma.

Preparation of response force and movement direction: onset effects on the lateralized readiness potential

Two experiments assessed the preparatory effects of advance information about response force and movement direction on the lateralized readiness potential (LRP). In a choice reaction time (RT) task, an imperative stimulus required an isometric flexion or an extension of the left or right index finger. Prior information about response force or about movement direction reduced RT and shortened the interval from the onset of the imperative stimulus up to the onset of the LRP. Advance information, however, about direction but not about force decreased the interval from LRP onset to the onset of the overt response. The identical pattern of results was obtained in a second experiment, in which each participant performed both precue conditions. The findings of both experiments support the notion that response force is specified before movement direction. These results are consistent with the view accordingly different mechanisms are involved in the specification of muscle force and movement direction.

Effect of corneal thickness on the accuracy of intraocular pressure measurement in rabbits after excimer laser photoablation

PURPOSE

To determine whether intraocular pressure (IOP) measurements using pneumotonometry and Tono-Pen tonometry are accurate after excimer laser photoablation of the central cornea in rabbits.

SETTING

Department of Ophthalmology, Scott & White Hospital, Texas A & M University College of Medicine, Temple, Texas, USA.

METHODS

Ten rabbits had excimer laser phototherapeutic keratectomy (PTK) in the right eye to thin the central corneal thickness (CCT) by approximately 20%. The left eye served as the control. The diameter of each PTK was 6.0 mm. Four weeks later, the rabbits were examined under general anesthesia. The eyes were cannulated, and IOP was maintained at 10, 20, and 30 mm Hg and measured using an IOP transducer, Tono-Pen, and pneumotonometer at each pressure level. The readings were compared.

RESULTS

One rabbit was excluded from the study because of recurrent erosions and corneal edema. There was no statistically significant difference in measurement error between the operated eye and control eye for the Tono-Pen (P = .12) or pneumotonometer (P = .35). There were significant differences in measurement error as pressure increased for the Tono-Pen (P < .01) and pneumotonometer (P < .01). The increase in measurement error with the increase in pressure was similar in the 2 eyes: Tono-Pen (P = .96) and pneumotonometer (P = .55). A paired t test showed the observed CCT was comparable (P = .79) in the pre-laser right eyes (mean 400.56 microm +/- 11.29 [SD]) and control eyes (mean 401.78 +/- 19.78 microm).

CONCLUSION

Photoablation of approximately 20% of the CCT in rabbits by excimer laser PTK did not significantly alter the accuracy of IOP measurements by the Tono-Pen or pneumotonometer.

Novel interaction between the transcription factor CHOP (GADD153) and the ribosomal protein FTE/S3a modulates erythropoiesis

The transcription factor CHOP (GADD153) heterodimerizes with other C/EBP family members, especially C/EBPbeta, thus preventing their homodimerization and binding to DNA sequences specific for the homodimers. Some CHOP-C/EBP heterodimers apparently bind to alternative DNA sequence and thereby regulate the transcription of other genes. Recently, we demonstrated that CHOP is up-regulated during certain stages of erythroid differentiation and that ectopic overexpression of CHOP enhances this process (Coutts, M., Cui, K., Davis, K. L., Keutzer, J. C., and Sytkowski, A. J. (1999) Blood 93, 3369-3378). In the present study, we report that CHOP also interacts with another non-C/EBP protein designated v-fos transformation effector (FTE) (Kho, C. J., and Zarbl, H. (1992) Proc. Natl. Acad. Sci. U. S. A. 89, 2200-2204), which is identical to ribosomal protein S3a (Metspalu, A., Rebane, A., Hoth, S., Pooga, M., Stahl, J. , and Kruppa, J. (1992) Gene (Amst.) 119, 313-316). Bacterially expressed His-CHOP and in vitro translated (35)S-labeled FTE/S3a-Gal4 fusion protein co-immunoprecipitated using anti-CHOP antibodies, and both anti-CHOP and anti-FTE/S3a antibodies co-immunoprecipitated CHOP and FTE/S3a from lysates of Rauscher murine erythroleukemia cells overexpressing both proteins. The in vivo interaction of CHOP and FTE/S3a was also demonstrated in cells overexpressing FTE/S3a but with endogenous expression levels of CHOP. Western blot analysis demonstrated co-localization of CHOP and FTE/S3a in both the cytosol and the nuclei of non-transfected cells. Overexpression of FTE/S3a inhibited differentiation of Rauscher cells induced either by erythropoietin or by dimethyl sulfoxide. This inhibition was reversed partially by simultaneous overexpression of CHOP or of antisense fte/S3a. FTE/S3a appears to be a bifunctional ribosomal protein that regulates CHOP and, hence, C/EBP function during erythropoiesis.

Mismatch repair proteins and microsatellites hit clinical practice

Hereditary nonpolyposis colon cancer (HNPCC) is one of the most common familial cancers with characteristic molecular changes that are different from those found in familial adenomatous polyposis (FAP) coli. Genetic mutations in the germline and somatic cells lead to loss of expression of one of the two most commonly involved mismatch repair genes, hMSH2 or hMLH1, and consequently, to expansion of certain repetitive DNA sequences (microsatellite instability (MSI)). The paper describes a distinct subtype of "HNPCC-like" sporadic colonic carcinoma that can easily be identified by immunohistochemistry. Recognition of this subtype of colonic cancer is important because it occurs in the younger age group and is associated with better survival, but also a five-fold chance of developing a second colorectal carcinoma compared to "conventional" colorectal carcinomas.

Regulation of drug sensitivity by ribosomal protein S3a

When bcl-2 is immunoprecipitated from (32)P-labeled cell extracts of all-trans retinoic acid (ATRA)-treated acute myeloblastic leukemia (AML) blasts, a phosphorylated protein of approximately 30 kd is coprecipitated. This protein has been identified as ribosomal protein S3a. The biologic effects of S3a include favoring apoptosis and enhancing the malignant phenotype. We sought to determine whether S3a, like bcl-2, influenced the response of cells to chemotherapeutic drugs and ATRA. Cell lines were studied in which S3a was genetically increased or disrupted; increased S3a was regularly associated with increased plating efficiency and increased sensitivity to either cytosine arabinoside (ara-C) or doxorubicin (DNR). S3a did not affect the sensitivity of cells to paclitaxel. Pulse exposures to either (3)HTdR or ara-C showed a greater percentage of clonogenic cells in the S phase of the cell cycle in cells with increased S3a than in controls. Cells with increased S3a responded to ATRA by increased ara-C or DNR sensitivity, whereas cells with reduced S3a protein were either protected by ATRA or not affected. We studied cryopreserved blast cells from patients with AML or chronic myelomonocytic leukemia (CMML). S3a protein levels were heterogeneous in these populations. In 32 cryopreserved blast populations, S3a levels were significantly correlated with both bcl-2 and with cell growth in culture. As in cell lines, high S3a in cryopreserved blasts was associated with ATRA-induced sensitization to ara-C. No significant association was seen between S3a levels and response to treatment.

Corneal subepithelial nodular scarring treated with phototherapeutic keratectomy in a child with Rothmund-Thomson syndrome

PURPOSE

To report the use of excimer laser phototherapeutic keratectomy (PTK) in the treatment of corneal subepithelial nodular scarring in a child with Rothmund-Thomson syndrome (RTS), a form of ectodermal dysplasia.

METHODS

A case report and review of the literature.

RESULTS

Excimer laser PTK successfully treated the recurrent anterior stromal fibrosis and irregular astigmatism, facilitating visual development. The use of excimer laser PTK prevented the development of dense amblyopia in this child.

CONCLUSION

This case demonstrates an indication for excimer laser PTK in the pediatric population.

Photoaffinity labeling and mass spectrometry identify ribosomal protein S3 as a potential target for hybrid polar cytodifferentiation agents

The ability of a novel class of hybrid polar compounds (HPCs) to induce differentiation and consequent cessation of proliferation of transformed cells has led to their development as potential chemotherapeutic agents in the treatment of cancer. Suberoylanilide hydroxamic acid (SAHA) is a prototype of a family of hydroxamic acid based compounds (SAHA-like HPCs) that can, at micromolar concentrations, induce a variety of transformed cell lines to differentiate. The mechanism of action of the HPCs is not entirely understood. Searching for a cellular target of the SAHA-like HPCs, we synthesized a photoaffinity labeling reagent structurally based on SAHA, and probed for SAHA-binding proteins in murine erythroleukemia (MEL) cells. Photoaffinity labeling in cell free extracts identified a 32-kDa protein (p32) that was specifically labeled by the photoaffinity reagent. Cell fractionation assays localized p32 to the P100 fraction. p32 was partially purified and identified by mass spectrometry as the 40 S ribosomal protein S3. Expression of epitope-tagged S3 in bacterial lysates followed by photoaffinity labeling confirmed its specific labeling. Identification of a cytodifferentiation agent target may shed light on the mechanism by which the SAHA-like HPCs exert their antitumor effects.

Preoperative treatment of rectal cancer with radiation, chemotherapy and hyperthermia: analysis of treatment efficacy and heat-shock response

Preoperative treatment of locally advanced rectal cancer with radiation, chemotherapy and hyperthermia is analyzed with regard to heat-shock response. In 23 patients with locally advanced rectal cancer (uT3/uT4), hyperthermia was administered in combination with radiotherapy and chemotherapy. In parallel, the effect of the treatment on levels of the heat-shock proteins HSP27 and inducible HSP70 in tumors and surrounding tissues was investigated by Western blotting. The patients' sera were also examined for autoantibodies against HSPs. HSP27 and inducible HSP70 were detected in most rectal tumors and surrounding tissues before and after treatment. HSP27 and inducible HSP70 levels had changed in 10 tumors after treatment. However, prior to treatment, there existed an unexpected diversity in HSP levels in the tumors and surrounding tissue. Hyperthermia doses in cumulative minutes for which 90% of the tumor is above the reference temperature (cum min T90 > or = 15 min) led to increased survival and response compared to that of a control group of patients treated without or with low-dose hyperthermia (cum min T90 < 15 min). However, there was no correlation to different expression of the HSPs. Hyperthermia as used in this setting does not lead to any sustained expression of HSPs in either the tumor or the surrounding tissue.

On-line performance assessment using rating scales

The purpose of this paper is to report on the development of the on-line performance assessment instrument--the Assessment of Motor and Process Skills (AMPS). Issues that will be addressed in the paper include: (a) the establishment of the scoring rubric and its implementation in an extended Rasch model, (b) training of raters, (c) validation of the scoring rubric and procedures for monitoring the internal consistency of raters, and (d) technological implementation of the assessment instrument in a computerized program.

Colocalization of single ribosomes with intermediate filaments in puromycin-treated and serum-starved mouse embryo fibroblasts

Previous experiments have revealed a relatively weak electrostatic binding capacity of in vitro reconstituted intermediate filaments (IFs) as well as of natural IFs of whole cell mount preparations for purified ribosomal particles of mammalian origin. In order to demonstrate that such associations also occur in vivo, intact cells were subjected to double immunofluorescence microscopy using antibodies directed against vimentin and ribosomal protein S17. Since in proliferating cells the majority of the ribosomal particles are assembled into polyribosomes and these are to a great extent associated with microfilaments, in vitro cultured mouse embryo skin fibroblasts (MSF cells) were treated with puromycin to allow the formation of single ribosomes. Employing confocal laser scanning microscopy, the ribosomes were detected in colocalization with vimentin IFs. Disassembly of polyribosomes was also achieved by serum starvation of cultured cells. In this case, MSF cells of a low passage attained an extended and flattened appearance with the vimentin IFs being directly associated with the cell nuclei, radiating into the peripheral areas of the cells or showing a stress fiber-like distribution. In both cases, considerable quantities of ribosomal material were seen in close neighborhood to vimentin IFs. Frequently, these ribosome-IF associations were coaligned with microtubules and they also surrounded myosin I-decorated stress fibers. Double labeling with the vital, RNA-specific fluorochrome SYTO 14 produced a fluorescence pattern largely superimposable on that of ribosomal protein S17. Treatment of the starved cells with either demecolcine or cytochalasin D had an only moderately disturbing effect on vimentin IF distribution and the ribosomes stayed in contact with the vimentin IFs. On the basis of these results, it is conceivable that IFs play a role in the storage of ribonucleoprotein particles in general and non-translating ribosomes in particular in the cytoplasm of animal cells. In addition, the often seen coalignment of IFs with microtubules and microfilaments might serve facilitated and directional transport of ribonucleoprotein particles from the nucleus to peripheral areas of the cell.

The 80S rat liver ribosome at 25 A resolution by electron cryomicroscopy and angular reconstitution

BACKGROUND

The ribosome is central to protein synthesis in all living organisms. Single-particle electron cryomicroscopy has recently led to the determination of three-dimensional structures of bacterial ribosomes to approximately 20 A, which have since revolutionised our understanding of ribosomal function. The structure we present here of the 80S rat liver ribosome leads the way to similar progress for mammalian ribosomes.

RESULTS

Among the new details revealed by our 25 A structure of the 80S rat liver ribosome are channels within the subunits, a large 'flat ribosomal surface' (FRS) on the outer surface of the large subunit and structural extensions of the mammalian compared to the bacterial ribosome. The main large subunit channel in both the bacterial and the mammalian species starts at the peptidyl transferase centre, below the central protuberance, and ends in the FRS, at the lower back of the large subunit. Structurally, the channels of both species can be directly superimposed.

CONCLUSIONS

The mammalian structural extensions--none of which trespass the FRS--can be interpreted in terms of rRNA inserts and additional protein content over that of bacterial ribosomes. The main large subunit channel, which ends at the FRS, is the best candidate for the exit channel for proteins targeted for the endoplasmic reticulum.

Identification and characterization of heat shock protein 27 protein species in human myocardial two-dimensional electrophoresis patterns

Immunostaining of heat shock protein 27 (Hsp27) protein species on two-dimensional electrophoresis (2-DE) gels with enhanced sensitivity yields 59 spots reacting with anti-Hsp27 antibodies. Recombinant Hsp27 exists in 2-DE as two major protein species which comigrate in the human myocardial pattern with Hsp27 spots C754 and D899 as defined in the heart high-performance 2-DE database (http://www.mdc-berlin.de/emu/heart/). Preparative electrophoresis of human myocardial proteins and analysis of the enriched mass range 20-30 kDa by 2-DE revealed eight protein spots (C438, C582, C658, C697, C754, C595, C750) from the human myocardial database and a new spot not previously detected on silver-stained gels. These spots were identified as Hsp27 protein species by enzymatic in-gel-digestion and analysis by matrix assisted laser desorption-ionization (MALDI) peptide mass fingerprinting and, in part, MALDI-post source decay sequencing of single fragments. Possible post-translational modifications were investigated: immunostaining tests with anti-phospho-serine/-threonine/-tyrosine antibodies, although positive for other myocardial proteins, were negative for presumed Hsp27 protein species; likewise, periodate-glycostaining assays and biotinylation screening did not detect modifications in the investigated Hsp27 protein species.

Abundance and location of the small heat shock proteins HSP25 and alphaB-crystallin in rat and human heart

BACKGROUND

In the heart, there are high constitutive levels of the two related small heat shock proteins, HSP25 and alphaB-crystallin. To gain insight into their functional role, we have analyzed abundance and location of both proteins in rat and human hearts at different stages of development and in diseased state.

METHODS AND RESULTS

Immunoblotting analysis of rat ventricular tissue at fetal, neonatal, and adult stages reveals the level of HSP25 to decline strongly during development, whereas the level of alphaB-crystallin remains nearly constant. In parallel, the portion of phosphorylated isoforms of HSP25 decreases as shown by two-dimensional polyacrylamide gel electrophoresis. HSP25 is detected in cardiomyocytes and endothelial and vascular smooth muscle cells, whereas alphaB-crystallin is detected in cardiomyocytes only by immunofluorescence and immunoelectron microscopy. Both proteins colocalize in the I-band and M-line region of myofibrils in cardiomyocytes. In diseased and transplanted adult human hearts, HSP25 and alphaB-crystallin levels are considerably elevated compared with fetal hearts. In failing adult human hearts, phosphorylated isoforms of HSP25 predominate, and cardiomyocytes with a partial dislocation of HSP25 and alphaB-crystallin are observed.

CONCLUSIONS

Differential accumulation and location of HSP25 and alphaB-crystallin in heart tissue during development imply distinct functions of both proteins, which seem to be involved in organization of cytoskeletal structures. As judged by level, phosphorylation state, and location of both small heat shock proteins, diseased adult human hearts share features with fetal hearts.

Intractable Crohn's colitis and perianal disease responding to cyclophosphamide and epirubicin

A case is reported where intractable Crohn's disease responded to chemotherapy for breast carcinoma. The drug most likely responsible was cyclophosphamide. Cyclophosphamide may have a role in the management of inflammatory bowel disease, but this needs to be confirmed before it can be recommended as a treatment option.

The signal transducer gp130--bacterial expression, refolding and properties of the carboxy-terminal domain of the cytokine-binding module

Gp130 is the signal transducing receptor subunit of the so-called interleukin-6-type cytokines. This transmembrane protein is a member of the cytokine-receptor superfamily predicted to consist of six fibronectin-type-III-like domains in its extracellular part. The second and the third domain constitute the so-called cytokine-binding module. Domain 2 is characterized by a set of four conserved Cys residues, domain 3 by a conserved WSXWS motif. As a first approach to a more detailed characterization of the cytokine-binding domains of human gp130, we have expressed in Escherichia coli two forms of domain 3 differing in length. Both proteins were purified and refolded in a single step applying size-exclusion chromatography. According to the rotational correlation times deduced from fluorescence anisotropy decay, they do not form aggregates. CD and fluorescence spectroscopy were used to study thermal unfolding and denaturation by guanidinium hydrochloride. It was shown that N- and C-terminal extension by residues of the adjacent hinge regions substantially increase the thermal stability of the domain, which is conceivable from a molecular model. These results are the basis for further structural investigation by NMR spectroscopy.

Protein environment of mRNA at the decoding site of 80S ribosomes from human placenta as revealed from affinity labeling with mRNA analogs--derivatives of oligoribonucleotides

Affinity labeling of 80S ribosomes from human placenta has been studied using various mRNA analogs, namely, 2',3'-O-[4-(N-2-chloroethyl)-N-methylamino]benzylidene derivatives of oligoribonucleotides (Up)(n-1)U[32P]pC (n = 3, 6 or 12) and AUGU3[32P]pC as well as ([4-(N-2-chloroethyl)-N-methylamino]benzylmethyl-[5'-32P]-phospham ide derivatives of pAUGUn (n = 3 or 6). Labeling of 80S ribosomes with the derivatives of oligouridylates was carried out in complexes obtained nonenzymatically in the presence of saturating amounts of Phe-tRNA(Phe). Complexes with derivatives bearing AUG codon were obtained using a fractionated lysate from rabbit reticulocytes which contained protein translation factors and was deprived from endogeneous ribosomes and mRNAs. In all cases, 40S subunits were labeled preferentially. Within the subunits, both 18S rRNA and proteins were found to be modified. Sites of cross-linking in 18S rRNA have been identified earlier. Here, it is shown that the main targets of cross-linking among the ribosomal proteins were S3 and S3a (with minor modification of S26) for the 3'-derivatives of (Up)5UpC and (Up)11UpC. For the same derivative of (Up)2UpC, the reverse modification pattern was observed. 5'-derivatives of pAUGUn were cross-linked to proteins S3 and S3a in comparable extent; 3'-derivative of AUGU3pC modified protein S3a preferentially.

Oncocytic cardiomyopathy: a rare cause of unexpected early childhood death associated with fitting

A 15-month-old girl died unexpectedly in hospital following a five-day history of intermittent cardiac arrhythmias and convulsions preceded by several weeks of occasional vomiting. Autopsy revealed subendocardial nodules in the left ventricle, and tricuspid and mitral valves that were composed of aggregated large cells with foamy, pale pink cytoplasm characteristic of oncocytic cardiomyopathy. Fat stains were positive for neutral lipid and phospholipid and electron microscopic examination revealed numerous irregular mitochondria within affected cells. Examination of the brain revealed no structural or histologic abnormalities, anoxic damage or thromboembolic material. Oncocytic cardiomyopathy, though rare, may cause unexpected death in previously well young children with quite variable preceding clinical symptoms and signs which include fitting. Although the aetiology is unknown there is evidence that mitochondrial dysfunction may be involved.

[Development of a clinical-radiological CD-ROM database for focal lesions of the liver]

PURPOSE

The development of a CD-ROM database for continuous acquisition and archiving of interesting radiologic cases is described. As a pilot study radiologic images of focal lesions of the liver were collected.

METHODS

The database runs on a PC (80486 DX2, 66 MHz, 16 MB RAM), which is connected to the clinic network, a high quality x-ray scanner and a CD-ROM writer. Radiologic images can be inserted into the database either by scanner or by image transfer via network. The database is designed using Access 2.0. Well documented cases were chosen retrospectively, manipulated and archived.

RESULTS

308 images of 12 focal lesions with a capacity of 802 MB were stored on CD-ROM. Per case a storage capacity of 40-75 MB is necessary for image raw material, 15-25 MB are necessary for the postprocessed data. Spatial resolution is 190 dpi (3000 pixel/40 cm). Clinical data, radiological diagnosis coded by modified ACR index and a compressed icon of the images are stored on PC, the image data are stored on CD-ROM. 2.5 hours per case are needed for the complete acquisition, manipulation and archiving procedure, but improved hardware configuration can reduce the time significantly.

CONCLUSION

The described database allows continuous archiving of interesting radiologic cases on PC. ACR index is suited for a quick search of a specific combination of radiologic images and diagnosis from different modalities.

Cytoprotective mechanisms in cultured cardiomyocytes

Tumor necrosis factor-alpha (TNF-alpha), a potent cytokine mainly secreted by macrophages exerts pleiotropic effects on different cell types. However, the intracellular mediators of its action are not yet well characterized. To get an insight into endogenous cytoprotective mechanisms, we developed an in vitro model based on cultured cardiomyocytes treated with TNF-alpha at which we examined gene expression of heat shock proteins (HSP-27, HSP-70 and ubiquitin). Cardiomyocytes were isolated from the hearts of 18 day old fetal mice by enzymatic dissociation and grown in minimum essential medium containing 10% fetal calf serum. Spontaneously contractile cells were serum deprived for 24 h and treated with TNF-alpha (25 ng/ml) for 1, 2, 4, 6, 8, 12, and 24 h After each incubation, cells were processed to extract total proteins for Western and total RNA for Northern blot analyses. TNF-alpha induced arrhythmias and cessation of spontaneous contractions in a concentration and time dependent manner. Steady state (ubiquitin) or undetectable mRNA levels (HSP-27, HSP-70) were drastically induced (> 4 fold for all three genes vs untreated control cells) by TNF-alpha, reaching maximal values between 6-8 h of stimulation. Thereafter, the expression of these stress genes declined but remained elevated as compared to control. By Western blot analysis, we found increased multiple bands of ubiquitin protein conjugates in TNF-alpha treated cells whereas no significant change in HSP-27 protein accumulation until 12 h was observed as compared to control. 24 h of TNF-alpha incubation resulted in partial cellular necrosis. Our results indicate that TNF-alpha induces in cardiomyocytes transiently gene expression for cytoprotective molecules like HSP-27, HSP-70 and ubiquitin, suggesting these stress proteins to participate in subsequent defense mechanisms, for example in postischemic myocardial recovery.