Immunohistochemical somatostatin receptor expression in insulinomas

Insulinomas are rare pancreatic neuroendocrine tumours. Most patients can be cured with surgery, but patients with a metastatic disease show impaired survival. The aim of this study was to evaluate somatostatin receptor (SSTR) 1-5 expression in insulinomas and to correlate the expression profile with clinicopathological variables and with patient outcome. This retrospective study involved 52 insulinoma patients. After histological re-evaluation, formalin-fixed paraffin-embedded tissue samples were processed into tissue microarrays and stained immunohistochemically with monoclonal SSTR1-5 antibodies. All the 52 tumours (49 non-metastatic, 3 metastatic) expressed at least one SSTR subtype. SSTR2 was expressed most frequently (71%), followed by SSTR3 (33%), SSTR1 (27%), SSTR5 (6%) and SSTR4 (0%). SSTR3 expression was associated with a larger tumour size (median diameter 19 mm vs. 13 mm, p = 0.043), and SSTR3 and SSTR5 expression were associated with impaired overall survival [HR 3.532 (95% CI 1.106-11,277), p = 0.033, and HR 6.805 (95% CI 1.364-33.955), p = 0.019 respectively]. Most insulinomas express SSTR2, which may be utilized in diagnostic imaging, and in planning individualized treatment strategies for insulinoma patients. Further studies are needed to clarify the association between SSTR profile and overall survival.

Review of data quality assessment frameworks experiences around Europe

In the first phase of its work, WP6 has explored and synthesized existing knowledge and experiences on data quality assurance frameworks (DQAFs) in the context of cross-border sharing of federated secondary use health data. Our aim was to identify good practices within this area and develop a first set of corresponding recommendations. The recommendations reflect the synthesis of results from three parallel lines of work, each utilizing a different methodology: a) thematic workshops and partner meetings, b) analysis of existing data-sharing initiatives, and c) a scoping literature review. Our analysis of literature and existing health data initiatives suggest that currently deployed DQAFs cannot as such serve as platforms or models for an EHDS-wide data quality solution. There is an agreement in principle, that reliability, relevance, timeliness, coherence, coverage and completeness should be incorporated in a DQAF as measurable dimensions of data quality. We aim towards a working definition of data quality, which will be able to reflect the reality of the data, as well as its fitness for purpose from the perspective of potential users.

• We recommend focusing efforts on transparency at the level of data holder institutions across Member States in relation to adoption of regular audits, a well-developed DQAF and clear procedures with regard to processing the data.

• In the medium to longer-term EHDS nodes could promote and support the development of a benchmarking process, which will assist data managers and data holder institutions with alignment against a Europe-wide approach to measuring data quality within and across Member States.

Review of interoperability standards as data quality supporting elements

WP6 has approached the target of supporting trustworthy secondary use of health and health care data through two operational objectives: developing the EHDS data quality assurance framework for real-world health data and developing the EHDS secondary use Semantic Interoperability Framework. For the latter objective, several interoperability standards were identified in accordance with the EHDS2 data life cycle and user's journey approach, hence focusing on data discoverability (at data source and variable levels), communication support across nodes and on development of common data models. Selection was based on active participation of WP6 leaders in various pertinent workshops and interactive activities, both in the framework of TEHDAS (Stakeholder and Project Forum meetings) as well as other relevant initiatives (e.g. the PHIRI project). Input was also sought from Commission representatives and EU-level regulatory authorities. In a first step, standards were catalogued based of features such as typology of interest, utility and application domains. In the next phase we organised virtual semi-structured interviews with key representatives of over 20 standards (incl. HL7, SNOMED, CDISC, DCAT, OMOP etc.). The focus of the interviews targeted experiences in standards’ actual use, challenges in their implementation, issues of maintenance and sustainability, as well as undergoing collaborations and developments. Sessions were recorded and subsequently the transcripts of discussion extracted automatically. The process of analysing interview materials is presently ongoing, using an adapted version of the Common Assessment Method for Standards and Specifications (CAMSS) v.4.0.0. toolkit. Interim results will be discussed within the Joint Action meeting activities in June 2022, to produce a version for wider stakeholder dialogue later in the fall. Results and recommendations generated through this process will also be presented for discussion with the workshop audience.

Acromegaly caused by a GHRH-producing pancreatic neuroendocrine tumor: a rare manifestation of MEN1 syndrome

SUMMARY

Multiple endocrine neoplasia type 1 NM_001370259.2(MEN1):c.466G>C(p.Gly156Arg) is characterized by tumors of various endocrine organs. We report on a rare, growth hormone-releasing hormone (GHRH)-releasing pancreatic tumor in a MEN1 patient with a long-term follow-up after surgery. A 22-year-old male with MEN1 syndrome, primary hyperparathyroidism and an acromegalic habitus was observed to have a pancreatic tumor on abdominal CT scanning, growth hormone (GH) and insulin-like growth factor 1 (IGF1) were elevated and plasma GHRH was exceptionally high. GHRH and GH were measured before the treatment and were followed during the study. During octreotide treatment, IGF1 normalized and the GH curve was near normal. After surgical treatment of primary hyperparathyroidism, a pancreatic tail tumor was enucleated. The tumor cells were positive for GHRH antibody staining. After the operation, acromegaly was cured as judged by laboratory tests. No reactivation of acromegaly has been seen during a 20-year follow-up. In conclusion, an ectopic GHRH-producing, pancreatic endocrine neoplasia may represent a rare manifestation of MEN1 syndrome.

LEARNING POINTS

Clinical suspicion is in a key position in detecting acromegaly. Remember genetic disorders with young individuals having primary hyperparathyroidism. Consider multiple endocrine neoplasia type 1 syndrome when a person has several endocrine neoplasia. Acromegaly may be of ectopic origin with patients showing no abnormalities in radiological imaging of the pituitary gland.

A Family With A20 Haploinsufficiency Presenting With Novel Clinical Manifestations and Challenges for Treatment

BACKGROUND

Tumor necrosis factor α-induced protein 3 gene (TNFAIP3, also called A20) haploinsufficiency (HA20) leads to autoinflammation and autoimmunity. We have recently shown that a p.(Lys91*) mutation in A20 disrupts nuclear factor κB signaling, impairs protein-protein interactions of A20, and leads to inflammasome activation.

METHODS

We now describe the clinical presentations and drug responses in a family with HA20 p.(Lys91*) mutation, consistent with our previously reported diverse immunological and functional findings.

RESULTS

We report for the first time that inflammasome-mediated autoinflammatory lung reaction caused by HA20 can be treated with interleukin 1 antagonist anakinra. We also describe severe anemia related to HA20 successfully treated with mycophenolate. In addition, HA20 p.(Lys91*) was found to associate with autoimmune thyroid disease, juvenile idiopathic arthritis, psoriasis, liver disease, and immunodeficiency presenting with specific antibody deficiency and genital papillomatosis.

CONCLUSIONS

We conclude that HA20 may lead to combination of inflammation, immunodeficiency, and autoimmunity. The condition may present with variable and unpredictable symptoms with atypical treatment responses.

Immune cell profiles of metastatic HER2-positive breast cancer patients according to the sites of metastasis

PURPOSE

Recent works have characterized that metastatic site can affect the tumour immune profiles and efficiency of cancer immunotherapies. The prognosis of HER2-positive breast cancer is associated with the characteristics of the tumour immune microenvironment, with immunological cells playing a central role in efficiency of HER2-targeted antibodies. Here we investigated the prognostic significance of different metastatic sites and their correlation to tumour immune profiles in HER2-positive breast cancer treated with trastuzumab.

METHODS

We collected all (n = 54) HER2-positive metastatic breast cancer patients treated with trastuzumab containing regimens at Oulu University Hospital 2009-2014. Pathological and clinical data were collected from electronic patient records. The tumour immune profiles were analysed from pre-treatment primary tumours using well-characterized immunological markers with computer-assisted immune cell counting.

RESULTS

Of the metastatic sites, only liver metastases were associated with poor prognosis (hazard ratio 1.809, 95% confidence interval 1.004-3.262), especially when presented as the primary site of metastases. Of the other sites, pulmonary metastases characterized a patient profile with trend to improved survival. Of the studied tumour immunological markers, patients with liver metastases had low densities of CD3⁺ T cells (p = 0.030) and M1-like macrophages in their primary tumours (p = 0.025). Of the other studied markers and sites, patients with pulmonary metastases had low STAB1⁺-immunosuppressive macrophage density in their primary tumours.

CONCLUSION

Our results suggest that the site of metastasis is associated with prognosis in HER2-positive breast cancer, highlighted by the poor prognosis of liver metastases. Furthermore, liver metastases were associated with adverse tumour immune cell profiles.

Serological Biomarker Panel in Diagnosis of Atrophic Gastritis and Helicobacter pylori Infection in Gastroscopy Referral Patients: Clinical Validation of the New-Generation GastroPanel® Test

BACKGROUND/AIM

Prompted by the increasing demand of non-invasive diagnostic tools for screening of gastric cancer (GC) risk conditions, i.e., atrophic gastritis (AG) and Helicobacter pylori (Hp) infection, the GastroPanel^® test (GP: biomarker panel of PGI, PGII, G-17, Hp IgG ELISA) that was developed in the early 2000's, was recently updated to a new-generation (unified GP) test version. This clinical validation study evaluated the diagnostic accuracy of the new-generation GP test in detection of AG and Hp among gastroscopy referral patients in a University Clinic.

PATIENTS AND METHODS

Altogether, 522 patients were enrolled among the patients referred for gastroscopy at the Gastro Center, Oulu University Hospital (OUH). All patients underwent gastroscopy with biopsies classified using the Updated Sydney System (USS), and blood sampling for GP testing.

RESULTS

Biopsy-confirmed AG was found in 10.2% (53/511) of the patients. The overall agreement between the GP and the USS classification was 92.4% (95%CI=90.0-94.6%), with the weighted kappa (κ_w) of 0.861 (95%CI=0.834-0.883). In ROC analysis using moderate/severe AG of the corpus (AGC2+) as the endpoint, AUC=0.952 (95%CI=0.891-1.000) and AUC=0.998 (95%CI=0.996-1.000) for PGI and PGI/PGII, respectively. Hp IgG antibody ELISA detected biopsy-confirmed Hp-infection with AUC=0.993 (95%CI=0.987-0.999).

CONCLUSION

The new generation GastroPanel^® is a precise test for non-invasive diagnosis of atrophic gastritis and Hp-infection in dyspeptic patients referred for diagnostic gastroscopy.

Finnish and Swedish prehospital emergency care providers' knowledge and attitudes towards pressure ulcer prevention

BACKGROUND

Despite the knowledge that transportation by emergency medical services may increase the risk of pressure ulcers (PU), there is still lack of knowledge about the possibility of prehospital emergency care providers to be a part of preventing and reducing the risk of PUs.

METHODS

A survey was carried out during 2017 in Finland and Sweden. Validated questionnaires were used.

RESULTS

A total of 179 (72.7%) Finnish and 188 (28.8%) Swedish prehospital emergency care providers participated in the study. The overall rate of correct answers and the mean total knowledge score was 58.8% (SD 21.8), 20/34, in the Finnish group and 70.5% (SD 15.7), 24/34, in the Swedish group (p < 0.000). The percent of the total and the mean attitude score was in the Finnish group 71.3% (SD 0.48), 37.1/52, and in the Swedish group 69.4% (SD 0.77), 36.1/52 (p < 0.813). Half of the Finnish and most of the Swedish participants felt they needed more education about PUs (Fin 50.2% & Swe: 76.0%).

CONCLUSIONS

Prehospital emergency care providers don't see themselves as responsible for PU prevention. Therefore, there is a need for increasing the level of knowledge on PU prevention and classification among prehospital emergency care providers. They could play a key role in developing methods to improve PU prevention and identifying patients in risk of developing PUs.

Correction to: Appendicolith appendicitis is clinically complicated acute appendicitis-is it histopathologically different from uncomplicated acute appendicitis

The authors regrets that a typo error found on their published paper. The correction are as follows.

Vastuullinen toiminnanohjausjärjestelmän kehittäminen kotihoidossa

Suomen tämän hetkinen strateginen tavoite on lisätä ikääntyneiden kotona asumista ja vähentää laitoshoidon määrää, mikä tarkoittaa lisääntyvää tarvetta kotihoidon palveluille. Samanaikaisesti hoito- ja hoivapalveluita tarvitsevien ikääntyvien määrä kasvaa suhteessa työikäisen väestön määrään ja kotihoidon asiakkaiksi ohjautuu yhä huonokuntoisempia ikäihmisiä. Kotihoidossa käytettävissä oleva työvoima tulee pystyä kohdentamaan tehokkaasti ja järkevästi asiakastarpeen mukaan, jotta laatua ja vaikuttavuutta voidaan ylläpitää. Toiminnanohjausjärjestelmistä on haettu ratkaisua henkilöstöresurssien optimointiin. Toiminnanohjausjärjestelmän käyttöönottoa arvioiva tutkimus toteutettiin Pirkkalan kunnan kotihoito-organisaatiossa. Projektin tavoitteena oli sujuvoittaa toiminnanohjausjärjestelmän käyttöönottoa kotihoidossa, pohtia toiminnanohjausjärjestelmän tarjoamien eri optimointivaihtoehtojen toimivuutta sekä saada toiminnanohjausjärjestelmä palvelemaan organisaatiota kokonaisuudessaan mahdollisimman hyvin. Tutkimuksen aineisto muodostui kotihoitajien työpäivien seurannasta, tiiminvetäjien haastattelusta, optimointityöpajasta ja esimiesten työpajoista. Tarkastellun kotihoito-organisaation toiminnanohjausjärjestelmän ensisijaisena tavoitteena on kohdentaa kotihoidon henkilöstöresurssit vastaamaan ikäihmisten tarpeita tehokkaasti, laadukkaasti ja vastuullisuustekijät huomioiden. Toiminnanohjausjärjestelmän käyttöä tukevat ja heti käyttöön otettavissa olevat suositukset ovat: Käyntien aikakriittisyyden tiukka arviointi sekä aikariittisten käyntien ajankohtien ja käynneille asetettujen aikavälien tarkistaminen; Työajan ylittyminen -vaihtoehdon salliminen optimoinnissa; Mahdollisimman suuren asiakas- ja hoitajajoukon yhtäaikainen optimointi ja Omahoitajuuden huomioiminen laadun tekijänä. Toiminnanohjausjärjestelmän tulisi olla järjestelmäkehittäjän toimesta räätälöitävissä yksilöllisten asiakastarpeiden mukaiseksi. Integroituvuus muiden järjestelmien kanssa on oleellinen tekijä tehokkaan ja toimivan kokonaisuuden saavuttamiseksi. Myös tarve joustavalle toiminnanohjausjärjestelmän jatkokehitykselle toimintaympäristön, osaamisen ja tavoitteiden muuttuessa tulisi huomioida. Näiden vaatimusten lisäksi toiminnan mittaaminen ainakin kustannusten, henkilöstön hyvinvoinnin ja palvelun laadun näkökulmista tulisi huomioida tietoon pohjautuvan toiminnanohjausjärjestelmän suunnittelussa. Toiminnanohjausjärjestelmän käyttöönotto on yksi keino kotihoidon toiminnan kehittämiselle, mutta se ei yksinään riitä turvaamaan kotihoidon vastuullista kehittämistä. Johtamisen perusajatuksena tulisikin olla, miten tarjottavien palveluiden laatu ja toiminnan eettisyys voidaan turvata kasvavien resurssipaineiden alla.

ColPortal, an integrative multiomic platform for analysing epigenetic interactions in colorectal cancer

Colorectal cancer (CRC) is the third leading cause of cancer mortality worldwide. Different pathological pathways and molecular drivers have been described and some of the associated markers are used to select effective anti-neoplastic therapy. More recent evidence points to a causal role of microbiota and altered microRNA expression in CRC carcinogenesis, but their relationship with pathological drivers or molecular phenotypes is not clearly established. Joint analysis of clinical and omics data can help clarify such relations. We present ColPortal, a platform that integrates transcriptomic, microtranscriptomic, methylomic and microbiota data of patients with colorectal cancer. ColPortal also includes detailed information of histological features and digital histological slides from the study cases, since histology is a morphological manifestation of a complex molecular change. The current cohort consists of Caucasian patients from Europe. For each patient, demographic information, location, histology, tumor staging, tissue prognostic factors, molecular biomarker status and clinical outcomes are integrated with omics data. ColPortal allows one to perform multiomics analyses for groups of patients selected by their clinical data.

Measurement(s)	miRNA • methylation • clinical history • histology • transcription profiling assay • microbiome
Technology Type(s)	DNA sequencing • clinical monitoring • RNA sequencing • amplicon sequencing • ex vivo photography with digital image analysis • methylation profiling by array
Factor Type(s)	tumor status
Sample Characteristic - Organism	Homo sapiens

Machine-accessible metadata file describing the reported data: 10.6084/m9.figshare.9785795

Appendicolith appendicitis is clinically complicated acute appendicitis-is it histopathologically different from uncomplicated acute appendicitis

PURPOSE

Acute appendicitis may present as uncomplicated and complicated and these disease forms differ both epidemiologically and clinically. Complicated acute appendicitis has traditionally been defined as an appendicitis complicated by perforation or a periappendicular abscess, and an appendicolith represents a predisposing factor of complicated disease. There are histopathological differences between uncomplicated acute appendicitis and the previously established traditional forms of complicated acute appendicitis, but to our knowledge, the histopathological differences between uncomplicated acute appendicitis and complicated acute appendicitis presenting with an appendicolith have not yet been reported. The study purpose was to assess these differences with two prospective patient cohorts: (1) computed tomography (CT) confirmed uncomplicated acute appendicitis patients enrolled in the surgical treatment arm of the randomized APPAC trial comparing appendectomy with antibiotics for the treatment of uncomplicated acute appendicitis and (2) patients with CT-verified acute appendicitis presenting with an appendicolith excluded from the APPAC trial.

METHODS

The following histopathological parameters were assessed: appendiceal diameter, depth of inflammation, micro-abscesses, density of eosinophils, and neutrophils in appendiceal wall and surface epithelium degeneration.

RESULTS

Using multivariable logistic regression models adjusted for age, gender, and symptom duration, statistically significant differences were detected in the depth of inflammation ≤ 2.8 mm (adjusted OR 2.18 (95%CI: 1.29-3.71, p = 0.004), micro-abscesses (adjusted OR 2.16 (95%CI: 1.22-3.83, p = 0.008), the number of eosinophils and neutrophils ≥ 150/mm² (adjusted OR 0.97 (95%CI: 0.95-0.99, p = 0.013), adjusted OR 3.04 (95%CI: 1.82-5.09, p < 0.001, respectively).

CONCLUSIONS

These results corroborate the known clinical association of an appendicolith to complicated acute appendicitis.

Impact of constitutional TET2 haploinsufficiency on molecular and clinical phenotype in humans

Clonal hematopoiesis driven by somatic heterozygous TET2 loss is linked to malignant degeneration via consequent aberrant DNA methylation, and possibly to cardiovascular disease via increased cytokine and chemokine expression as reported in mice. Here, we discover a germline TET2 mutation in a lymphoma family. We observe neither unusual predisposition to atherosclerosis nor abnormal pro-inflammatory cytokine or chemokine expression. The latter finding is confirmed in cells from three additional unrelated TET2 germline mutation carriers. The TET2 defect elevates blood DNA methylation levels, especially at active enhancers and cell-type specific regulatory regions with binding sequences of master transcription factors involved in hematopoiesis. The regions display reduced methylation relative to all open chromatin regions in four DNMT3A germline mutation carriers, potentially due to TET2-mediated oxidation. Our findings provide insight into the interplay between epigenetic modulators and transcription factor activity in hematological neoplasia, but do not confirm the putative role of TET2 in atherosclerosis.

Micropapillary Structures in Colorectal Cancer: An Anoikis-resistant Subpopulation

BACKGROUND/AIM

Micropapillary structures (MIPs) are focal piles of columnar cells without extracellular matrix contact, and common in serrated colorectal carcinoma (CRC). In order to characterize biology of MIPs in colorectal cancer (CRC), the proliferation and apoptosis rates, and survivin expression were compared between MIPs and other cancer epithelial cells of CRC (non-MIPs).

MATERIALS AND METHODS

We assessed 46 samples of normal colorectal mucosa, 62 carcinomas and 54 polyps for proliferation (Ki67), apoptosis (M30), and survivin expression by immunohistochemistry.

RESULTS

MIPs in carcinoma showed lower rates of proliferation and apoptosis than non-MIPs. A low rate of apotosis in MIPs was associated with poor prognosis in local carcinoma. In normal crypts, nuclear-to-cytoplasmic transition of survivin indicated epithelial cell maturation. Cancer cases showed increased cytoplasmic expression of survivin than normal mucosa and polyps. However, MIPs showed lower nuclear and cytoplasmic survivin expression than non-MIPs. Our findings suggest that MIPs represent a biologically distinct subpopulation of carcinoma cells with features of anoikis resistance and possibly quiescence.

Biodegradation of inorganic drug delivery systems in subcutaneous conditions

Despite extensive efforts to develop delivery systems for oral administration, subcutaneous (s.c.) injection remains the most common way to administer peptide drugs. To limit the number of frequent injections, sustained release systems that are easy to produce, suitable for various drugs, safe and biodegradable are urgently needed. Porous silicon (PSi) has been recognized to be one of the most promising materials for s.c. peptide delivery, but its biodegradation in s.c. tissue has not been studied in vivo, despite extensive in vitro research. In the present study, differently modified PSi microparticles were injected s.c. in mice, after which the morphology of the particles was thoroughly studied with transmission electron microscopy, micro-computed tomography and X-ray diffraction. Furthermore, histopathology of the s.c. tissue was analyzed to evaluate biocompatibility. To the best of our knowledge, this is the first systematic study which reveals the degradation behavior of various PSi materials in vivo. The PSi surface chemistry significantly affected the biodegradation rate of the s.c. injected microparticles. The most hydrophobic PSi microparticles with hydrocarbonized surface showed the lowest biodegradation rate while the hydrophilic microparticles, with oxide surface, degraded the fastest. The results from different empirical methods complemented each other to deduce the biodegradation mechanism of the inorganic delivery system, providing useful information for future development of s.c. carriers.

Abstract 1791: Spatially positioned tumor infiltrating lymphocytes predict survival in metastatic HER2 positive breast cancer treated with trastuzumab

Background: Disease outcomes of HER2+ breast cancers have dramatically changed after targeted therapies, such as trastuzumab, came to clinical practice but predictive factors for trastuzumab sensitivity and resistance are frequently unknown.

Methods: Metastatic breast cancer patients (n=48), who were treated with trastuzumab and had pre-treatment tumor samples available, were studied. The tumors were immunostained for T-cell (CD3, CD8) and NK-cell (CD56) markers and quantitative analysis of the immune cells was carried out using a computer-assisted image analysis in different tumor locations.

Results: High number of CD3 and CD8 positive T-cells was associated with significant survival benefit in the center of the tumor (CT) (p=0.007, p=0.001), but not in the invasive region. NK-cell tumor infiltration was infrequent and they could not be reliably analyzed. In a subgroup analyses, high density of CD8 CT cells was associated with significant survival benefit in non-bone only disease, in TX-3, and in ER+ tumors (p=0.006, p=0.003, p=0.001). Moreover, high CD8 CT cell density was associated with good trastuzumab responses (p=0.042).

Conclusion: High number of CD3 and CD8 positive tumor infiltrating lymphocytes in the CT area is associated with survival benefit in some patient groups with HER2+ breast cancer treated with trastuzumab. Furthermore, high number of CD8 CT cells predicts benefit from trastuzumab.

Citation Format: Jussi Pekka Koivunen, Tiia Honkanen, Tiina Moilanen, Peeter Karihtala, Juha Väyrynen, Markus Mäkinen. Spatially positioned tumor infiltrating lymphocytes predict survival in metastatic HER2 positive breast cancer treated with trastuzumab [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 1791. doi:10.1158/1538-7445.AM2017-1791

Collagen XVII expression correlates with the invasion and metastasis of colorectal cancer

Collagen XVII has a well-established role as an adhesion molecule and a cell surface receptor located in the type I hemidesmosome of stratified epithelia. Its ectodomain is constitutively shed from the cell surface and suggested to regulate the adhesion, migration, and signaling of cutaneous epithelial cells. Collagen XVII was not previously thought to be expressed by colon epithelial cells. Immunohistochemical analysis of tissue microarray samples of 141 cases of colorectal carcinoma showed that collagen XVII is expressed in normal human colonic mucosa and colorectal carcinoma. In colorectal carcinoma, increased collagen XVII expression was significantly associated with higher TNM stage. It also correlated with infiltrative growth pattern and tumor budding as well as lymph node and distant metastasis. Increased collagen XVII expression was associated with decreased disease-free and cancer-specific survival. Immunofluorescence staining of collagen XVII and its well-known binding partner laminin γ2 chain demonstrated a partial colocalization in normal and tumor tissue. In vitro, the overexpression of murine collagen XVII promoted the invasion of CaCo-2 colon carcinoma cells through Matrigel (BD Biosciences; Bedford, MA). To conclude, this study reports for the first time the expression of collagen XVII in colon epithelium and the association of increased collagen XVII immunoexpression with poor outcome in colorectal carcinoma.

Fluorescent probes as a tool for cell population tracking in spontaneously active neural networks derived from human pluripotent stem cells

Applications such as 3D cultures and tissue modelling require cell tracking with non-invasive methods. In this work, the suitability of two fluorescent probes, CellTracker, CT, and long chain carbocyanine dye, DiD, was investigated for long-term culturing of labeled human pluripotent stem cell-derived neural cells. We found that these dyes did not affect the cell viability. However, proliferation was decreased in DiD labeled cell population. With both dyes the labeling was stable up to 4 weeks. CT and DiD labeled cells could be co-cultured and, importantly, these mixed populations had their normal ability to form spontaneous electrical network activity. In conclusion, human neural cells can be successfully labeled with these two fluorescent probes without significantly affecting the cell characteristics. These labeled cells could be utilized further in e.g. building controlled neuronal networks for neurotoxicity screening platforms, combining cells with biomaterials for 3D studies, and graft development.

No evidence of RET germline mutations in familial pituitary adenoma

Pituitary adenomas are common in the general population. Although most of them are sporadic, some occur in a familial setting. In familial pituitary adenoma patients it is common that no germline defects are found after screening of aryl hydrocarbon receptor interacting protein (AIP) and other genes known to underlie the condition, suggesting the existence of yet unknown predisposition genes. Recently, the RET proto-oncogene was found to be a novel in vivo interaction partner of AIP in the pituitary gland. Here, we have screened patients from 16 AIP mutation negative (AIPmut-) pituitary adenoma families for RET germline mutations to assess whether RET could play a role in pituitary adenoma predisposition, similar to AIP. We found five novel germline RET changes: one in RET Exon 4 and the rest in noncoding regions of RET. Two changes, c.1560*G > A and -1285 G > A, were segregated in affected family members. We also analyzed the RET region with enhancer element locator (EEL) to identify RET regulatory elements, and to see whether the changes resided in these. None of the variants mapped to the regions predicted by EEL. Expression of RET was examined in ten AIPmut- and seven AIP mutation positive (AIPmut+) somatotropinomas by immunohistochemistry, with a trend showing reduced expression in the latter (P = 0.05). We conclude that the RET variants are presumably not related to pituitary adenoma predisposition, although reduced RET expression may play a role in AIP-related genesis of somatotropinomas.

High frequency of TTK mutations in microsatellite-unstable colorectal cancer and evaluation of their effect on spindle assembly checkpoint

Frameshift mutations frequently accumulate in microsatellite-unstable colorectal cancers (MSI CRCs) typically leading to downregulation of the target genes due to nonsense-mediated messenger RNA decay. However, frameshift mutations that occur in the 3' end of the coding regions can escape decay, which has largely been ignored in previous works. In this study, we characterized nonsense-mediated decay-escaping frameshift mutations in MSI CRC in an unbiased, genome wide manner. Combining bioinformatic search with expression profiling, we identified genes that were predicted to escape decay after a deletion in a microsatellite repeat. These repeats, located in 258 genes, were initially sequenced in 30 MSI CRC samples. The mitotic checkpoint kinase TTK was found to harbor decay-escaping heterozygous mutations in exon 22 in 59% (105/179) of MSI CRCs, which is notably more than previously reported. Additional novel deletions were found in exon 5, raising the mutation frequency to 66%. The exon 22 of TTK contains an A(9)-G(4)-A(7) locus, in which the most common mutation was a mononucleotide deletion in the A(9) (c.2560delA). When compared with identical non-coding repeats, TTK was found to be mutated significantly more often than expected without selective advantage. Since TTK inhibition is known to induce override of the mitotic spindle assembly checkpoint (SAC), we challenged mutated cancer cells with the microtubule-stabilizing drug paclitaxel. No evidence of checkpoint weakening was observed. As a conclusion, heterozygous TTK mutations occur at a high frequency in MSI CRCs. Unexpectedly, the plausible selective advantage in tumourigenesis does not appear to be related to SAC.

[Colorectal serrated lesions: current insight on their role in colorectal carcinogenesis]

The classification of colorectal cancer precursor lesions has become more accurate after the discovery of serrated polyps. These are characterized by saw-tooth-like epithelial growth pattern, and are the most significant group of colorectal cancer precursors after conventional adenomas. While conventional adenomas are characterized by tumour suppressor gene mutations and chromosomal instability, serrated adenomas harbour KRAS/BRAF mutations, inhibition of apoptosis, DNA hypermethylation, and microsatellite instability. These alterations occur in about 20% of colorectal cancers, and along with preserved serrated morphology suggest their origin in serrated polyps. The recognition of serrated polyps as colorectal cancer precursors is crucial for their follow-up.

The expression of AIP-related molecules in elucidation of cellular pathways in pituitary adenomas

Germline mutations in the aryl hydrocarbon receptor interacting protein (AIP) gene predispose to the development of pituitary adenomas. Here, we characterized AIP mutation positive (AIPmut+) and AIP mutation negative (AIPmut-) pituitary adenomas by immunohistochemistry. The expressions of the AIP-related proteins aryl hydrocarbon receptor (AHR), AHR nuclear translocator (ARNT), cyclin-dependent kinase inhibitor 1B encoding p27(Kip1), and hypoxia-inducible factor 1-alpha were examined in 14 AIPmut+ and 53 AIPmut- pituitary adenomas to detect possible expression differences. In addition, the expression of CD34, an endothelial and hematopoietic stem cell marker, was analyzed. We found ARNT to be less frequently expressed in AIPmut+ pituitary adenomas (P = 0.001), suggesting that AIP regulates the ARNT levels. AIP small interfering RNA-treated HeLa, HEK293, or Aip-null mouse embryonic fibroblast cells did not show lowered expression of ARNT. Instead, in the pituitary adenoma cell line GH3, Aip silencing caused a partial reduction of Arnt and a clear increase in cell proliferation. We also observed a trend for increased expression of nuclear AHR in AIPmut+ samples, although the difference was not statistically significant (P = 0.06). The expressions of p27(Kip1), hypoxia-inducible factor 1-alpha, or CD34 did not differ between tumor types. The present study shows that the expression of ARNT protein is significantly reduced in AIPmut+ tumors. We suggest that the down-regulation of ARNT may be connected to an imbalance in AHR/ARNT complex formation arising from aberrant cAMP signaling.

Local staging of rectal cancer using the black lumen magnetic resonance imaging technique

BACKGROUND AND AIMS

The treatment of rectal cancer is comprised of surgery and possible adjuvant therapy depending on the stage of the tumour. This prospective study evaluates the accuracy of magnetic resonance imaging (MRI) in the preoperative staging of rectal cancer using an endorectal and intravenous contrast.

MATERIALS AND METHODS

37 consecutive patients with rectal cancer were imaged using a mixture of ferumoxsil and methylcellulose endorectally, and a gadolinium contrast intravenously. 33 tumours were resected and 4 tumours were considered unresectable during operation. The images were reviewed for local staging of the tumours. A tumour confined to the rectal wall was classified as a negative finding and a tumour invading through muscularis propria as a positive finding. The results were correlated with the histopathologic t stage (n = 33), or the clinical status (n = 4).

RESULTS AND CONCLUSIONS

of 37 cases, 20 (51 %) were true positive, and 11 (28%) were true negative. There were 3 false negative and 3 false positive cases. The sensitivity was 87%, specificity 79%, and diagnostic accuracy 84%. for the non-contrast images the figures were 78%, 79% and 78%, respectively. We consider black lumen magnetic resonance imaging to be a useful method for preoperative local staging of rectal cancer.

Assessment of CPR-D skills of nurses in Göteborg, Sweden and Espoo, Finland: Teaching leadership makes a difference

INTRODUCTION

Construction of an effective in-hospital resuscitation programme is challenging. To document and analyse resuscitation skills assessment must provide reliable data. Benchmarking with a hospital having documented excellent results of in-hospital resuscitation is beneficial. The purpose of this study was to assess the resuscitation skills to facilitate construction of an educational programme.

MATERIALS AND METHODS

Nurses working in a university hospital Jorvi, Espoo (n=110), Finland and Sahlgrenska University Hospital, Göteborg (n=40), Sweden were compared. The nurses were trained in the same way in both hospitals except for the defining and teaching of leadership applied in Sahlgrenska. Jorvi nurses are not trained to be, nor do they act as, leaders in a resuscitation situation. Their cardiopulmonary resuscitation (CPR) skills using an automated external defibrillator (AED) were assessed using Objective Structured Clinical Examination (OSCE) which was build up as a case of cardiac arrest with ventricular fibrillation (VF) as the initial rhythm. The subjects were tested in pairs, each pair alone. Group-working skills were registered.

RESULTS

All Sahlgrenska nurses, but only 49% of Jorvi nurses, were able to defibrillate. Seventy percent of the nurses working in the Sahlgrenska hospital (mean score 35/49) and 27% of the nurses in Jorvi (mean score 26/49) would have passed the OSCE test. Statistically significant differences were found in activating the alarm (P<0.001), activating the AED without delay (P<0.01), setting the lower defibrillation electrode correctly (P<0.001) and using the correct resuscitation technique (P<0.05). The group-working skills of Sahlgrenska nurses were also significantly better than those of Jorvi nurses.

CONCLUSIONS

Assessment of CPR-D skills gave valuable information for further education in both hospitals. Defining and teaching leadership seems to improve resuscitation performance.

Teaching basic life support to nurses

BACKGROUND AND OBJECTIVE

Every member of healthcare personnel should be able to perform basic life support including defibrillation (CPR-D). The biggest cost of implementation is training and these costs need to be reduced. The purpose of this randomized study was to evaluate the applicability of distance learning as a method to teach CPR-D.

METHODS

Nurses (n = 56) working in a geriatric hospital were randomized into three groups. The first group was given the Internet-based CPR-D course and the second was given a traditional, small-group CPR-D course. A third group without specific training in CPR-D served as a control group. An objective structured clinical examination (OSCE) was performed 2 weeks after the courses with a manikin patient having a cardiac arrest.

RESULTS

The median score of all participants was 31/49 (range 21-38). The reliability of the checklist was adequate (Cronbach alpha 0.77). Nurses receiving traditional CPR-D performed better than those receiving the Internet-based course (median score 34 vs. 28, P < 0.05) and the control group (median score 34 vs. 26, P < 0.0001). Nurses receiving Internet-based course performed similarly as the control group (median score 28 vs. 26, ns).

CONCLUSIONS

Distance learning cannot substitute for traditional small-group learning.

Inverse regulation of preproendothelin-1 and endothelin-converting enzyme-1beta genes in cardiac cells by mechanical load

Mechanical stretch and para- and/or autocrine factors, including endothelin-1, induce hypertrophy of cardiac myocytes and proliferation of fibroblasts. To investigate the effect of mechanical load on endothelin-1 production and endothelin system gene expression in neonatal rat ventricular myocytes and fibroblasts, we exposed cells to cyclic mechanical stretch in vitro (0.5 Hz, 10-25% elongation, from 1 min to 24 h). Endothelin-1 peptide levels were measured from culture media of myocytes and fibroblasts and human umbilical vein endothelial cells (positive control) by specific radioimmunoassay. Preproendothelin-1 promoter activity was measured via transfection of reporter plasmids and mRNA levels with Northern blot analysis or quantitative RT-PCR. Activity of extracellular signal-regulated kinase was quantified with specific kinase assay. We found that stretching of myocytes activated preproendothelin-1 gene expression, including promoter activation, transient mRNA level increases, and augmented endothelin-1 secretion. In contrast, preproendothelin-1 gene expression was inhibited in stretched fibroblasts. Endothelin-converting enzyme-1beta mRNA levels elevated in stretched fibroblasts but decreased in stretched myocytes. Endothelin receptor type A mRNA levels declined in stretched myocytes, whereas levels were below detection in fibroblasts. Stretch activated extracellular signal-regulated kinase in myocytes, and when the kinase activity was pharmacologically inhibited, the preproendothelin-1 induction was suppressed. Transient overexpression of mitogen-activated ERK-activating kinase-1 induced preproendothelin-1 promoter in myocytes. In summary, mechanical stretch distinctly regulates endothelin system gene expression in cardiac myocytes and fibroblasts. The inhibition of the endothelin system may affect cardiac mechanotransduction and therefore provides an approach in treatment of load-induced cardiac pathology.

An electrospray ionization Fourier transform ion cyclotron resonance mass spectrometric study of the gas-phase stabilities and fragmentation of N-alkylammonium resorcarenes

Five N-alkylated ammonium resorcarene derivatives, differing either in the nitrogen atom or in the lower rim alkyl chain, were studied using electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry. The main purpose was to clarify the fragmentation and the relative stabilities of the protonated molecules by collision-induced dissociation (CID) experiments. The results indicate that fragmentation of the upper rim alkyl amino substituents at the 2-position occurs readily. Variation in the gas-phase stabilities of these molecules was also observed. In addition, the proposed fragmentation pathways are depicted.

Patterns of Dermal Exposure to Hazardous Substances in European Union Workplaces

Workplace dermal exposure assessment is a complex task that aims to understand the dynamic interaction between the skin and the hazardous substances present in the surrounding environment. A European project known as RISKOFDERM gathered dermal exposure data in 85 workplaces (industrial and other types) in five countries in Europe. In order to optimize data collection and to develop a representative picture of dermal exposure, scenarios (tasks made up of a series of activities) were grouped together into dermal exposure operation units (DEOs). The allocation of scenarios to relevant DEOs was achieved on the basis of similarities of exposure routes, tasks and professional judgement. Sampling and quantification procedures were based on the approaches recommended by the OECD protocol. The laboratories involved in the analysis of the samples participated in quality assurance programmes. This exercise resulted in 419 body measurements and 437 measurements on hands expressed in terms of formulation (product) in use. Exposures for a given scenario varied by several orders of magnitude. The extent and patterns of exposure were found to be dependent on various exposure determinants, including inter- and intra-scenario variations. Hands were found to be the most contaminated parts of the body. Exposure patterns for liquid and solid contaminants were different. On the basis of the analysis of the data presented here, the averaged results (median and 95th percentile) for a given DEO unit should not be used as a representative measure of dermal exposure for all scenarios within that DEO without taking the exposure determinants into account. However, the data could be used to develop an exposure matrix (indicative exposure distributions) for different types of scenario and workplace, using determinants of exposure and a Bayesian approach to integrating expert opinion.

Dual role of endothelin-1 via ETA and ETB receptors in regulation of cardiac contractile function in mice

An increase in coronary perfusion pressure leads to increased cardiac contractility, a phenomenon known as the Gregg effect. Exogenous endothelin (ET)-1 exerts a positive inotropic effect; however, the role of endogenous ET-1 in the contractile response to elevated load is unknown. We characterized here the role of ETA and ETB receptors in regulation of contractility in isolated, perfused mouse hearts subjected to increased coronary flow. Elevation of coronary flow from 2 to 5 ml/min resulted in 80 +/- 10% increase in contractile force (P < 0.001). BQ-788 (ETB receptor antagonist) augmented the load-induced contractile response by 35% (P < 0.05), whereas bosentan (ETA/B receptor antagonist) and BQ-123 (ETA receptor antagonist) attenuated it by 34% and 56%, respectively (P < 0.05). CV-11974 (ANG II type 1 receptor antagonist) did not modify the increase in contractility. These results show that endogenous ET-1 is a key mediator of the Gregg effect in mouse hearts. Moreover, ET-1 has a dual role in the regulation of cardiac contractility: ETA receptor-mediated increase in contractile force is suppressed by ETB receptors.

Expression of cyclooxygenase-2 in intestinal goblet cells of pre-diabetic NOD mice

Cyclooxygenase, the rate-limiting enzyme in prostaglandin synthesis, is expressed in constitutive (COX-1) and inducible (COX-2) isoforms. The COX-2 has been proposed to be involved in development of autoimmune type 1 diabetes (T1D). We examined COX-2 expression in the gut-associated lymphoid tissue (GALT), and found COX-2 was strongly expressed in goblet cells of non-obese diabetic (NOD) mice at the apical villi at the age of 2.5 weeks, clearly before the onset of insulitis, while the expression in the control BALB/c mice was weak or absent at all ages (P < 0.001). Lipopolysaccharide (LPS) given intraperitoneally slightly increased COX-2 expression in the goblet cells and epithelium of both NOD and BALB/c mice. High-resolution confocal microscopy showed that the surroundings of the goblet cells contained no COX-2, implying that the enzyme is synthesized by the goblet cells. The COX-2 is secreted from goblet cells into the intestinal lumen along with mucins. The COX-2 concentration in the goblet cell of BALB/c and especially of NOD mice was markedly higher than that in the intraepithelial lymphocytes or lamina propria macrophages. High mucin COX-2 from goblet cells may increase luminal prostaglandin synthesis, alter epithelial permeability, modulate intestinal immune responses and modify functional properties of the lymphocytes in the GALT, which all may be important for the initiation of the autoimmune phenomenon in the NOD mice.

Applicability of homogeneous exposure groups for exposure assessment in the chemical industry

The purpose of the study was to assess occupational exposure to chemicals, by taking the aspects presented in European standard EN 689 into account, especially with respect to homogeneous exposure groups and their suitability as the basis for exposure assessment. In addition, dermal exposure to chemicals was assessed when appropriate. The industries studied included a plywood factory, a paint factory and a sewage treatment plant of an oil refinery. The workers were classified into homogeneous exposure groups by the persons in charge of occupational health issues in the respective workplaces. The concentrations of the contaminants were measured in workplace air by breathing-zone and stationary sampling, and these approaches were compared. Dermal exposure was measured when applicable. The homogeneity of the grouping was tested with analysis of variance whenever possible. The tasks studied in plywood manufacturing fulfilled the criteria of homogeneous exposure groups for both respiratory and dermal exposure. The group of operators in the sewage treatment plant was highly homogeneous. The complicated organization of the tasks made the use of homogeneous exposure groups (HEG) unsuitable at the paint factory. These findings show that reliable exposure assessment cannot be achieved with a formal standard; instead, comprehensive occupational hygiene evaluation is needed. It should also have a great importance when exposure models are developed.

Expression of insulin-receptor substrate-1 and -2 in ovaries from women with insulin resistance and from controls

OBJECTIVE

To evaluate the role of insulin-receptor substrate (IRS)-1 and -2 in ovary dysfunction in women with insulin resistance.

DESIGN

Immunoblotting and immunohistochemical analyses of the localization and staining intensity of IRS-1 and IRS-2 in the ovaries of women with the polycystic ovary syndrome (PCOS) and gestational diabetes mellitus.

SETTING

Department of Obstetrics and Gynecology, Turku University Central Hospital.

PATIENT(S)

Sections of ovary were obtained at the time of cesarean section from five volunteers without medical complications and three patients with gestational diabetes mellitus. Paraffin-embedded ovary sections were selected from those on file from the department of pathology; four were from women with a histologic diagnosis of PCOS and seven were from women with endometriosis (controls).

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Protein expression of IRS in human ovary samples.

RESULT(S)

Immunoblotting with specific monoclonal and polyclonal antibodies showed the presence of 165-kDa and 183-kDa proteins that corresponded to the size of IRS-1 and IRS-2, respectively, in normal pregnant ovaries and human cultured follicles. Immunohistochemical staining showed that positive IRS-2 expression in antral follicles was restricted to theca internal cells in ovulatory ovaries but was distributed widely in all compartments of follicles in different stages in polycystic ovaries. Compared with follicles at a similar stage of development in ovulatory ovaries, follicles in polycystic ovaries showed decreased staining for IRS-1 in granulosa cells but increased staining for IRS-2 in theca internal cells. These features of IRS-1 and -2 expression were also noted in preantral and atretic follicles from patients with gestational diabetes mellitus compared with those who had uncomplicated pregnancy.

CONCLUSION(S)

This study highlights a shift of the follicular insulin signal protein from IRS-1 to IRS-2 in insulin-resistant states and suggests an association between this change and ovarian abnormality in PCOS and gestational diabetes mellitus.

New world, but not Old World, monkeys carry several genes encoding beta-microseminoprotein

It was shown by Southern hybridization that cotton-top tamarin and common marmoset, New World monkeys, carry three or more genes encoding beta-microseminoprotein, also known as PSP94. In contrast, the genomes of Old World monkeys, as represented by rhesus macaque and sacred baboon, contain a single gene. Clones containing three different genes encoding beta-microseminoprotein were isolated from a cotton-top tamarin genomic library. They carry two complete genes of four exons and a third gene lacking the first exon. The structure suggests that the three genes are functionally active and give rise to transcripts that are approximately 86% similar in sequence. By sequencing one gene in full, it was shown that the introns carry an excess of interspersed repeats, on average 29% of the introns consist of Alu repeats. A phylogenetic analysis demonstrated that the genes probably arose in New World monkeys after the separation from Old World primates.

Assessment of total exposure to phenol-formaldehyde resin glue in plywood manufacturing

OBJECTIVE

Respiratory and dermal exposure to phenol-formaldehyde resin-glue components used in plywood manufacturing were assessed.

METHODS

Formaldehyde and phenol were monitored in the workplace air. Formaldehyde was measured both in the breathing zones of the workers and at stationary sampling sites. Phenol was used as a marker agent for dermal exposure due to its near-nonvolatility at the temperatures occurring during the present study and to its ready absorption through the skin, causing systemic exposure in addition to local skin rashes. Sampling and analytical methods were developed to measure the dermal exposure to phenol. Sampling was accomplished with whole-body dosimetry using Tyvek coveralls and cotton gloves. In addition, a liquid chromatography method was developed for the analysis of phenol from dermal exposure samples.

RESULTS

As expected, formaldehyde was noted to be the major compound causing respiratory exposure. When exposure assessment was done on the basis of air samples collected both at stationary sampling sites and in the breathing zones of the workers the agreement between the results obtained was good. The dermal sampling revealed that the workers were exposed to phenol, but the risk for toxic effects was slight due to the low concentrations of urinary phenol.

CONCLUSIONS

We conclude that it is possible to use the stationary sampling method for the assessment of respiratory exposure in a plywood factory instead of the usually more complicated breathing-zone sampling. This study also demonstrates the importance of taking dermal exposure into account, at least due to the ability of the resins to cause skin rashes, in assessment of the exposure to chemicals in plywood manufacturing.

Separation of linoleic acid oxidation products by micellar electrokinetic capillary chromatography and nonaqueous capillary electrophoresis

In this work the suitability of micellar electrokinetic capillary chromatography (MEKC) and nonaqueous capillary electrophoresis (CE) to the analysis of the primary oxidation products of linoleic acid was studied with uncoated fused-silica capillaries. The primary autoxidation products of linoleic acid are the four hydroperoxide isomers 13-hydroperoxy-cis-9, trans-11-octadecadienoic acid, 13-hydroperoxy-trans-9, trans-11-octadecadienoic acid, 9-hydroperoxy-trans-10,cis-12-octadecadienoic acid, 9-hydroperoxy-trans-10, trans-12-octadecadienoic acid. Addition of a surfactant such as sodium dodecyl sulfate (SDS) or sodium cholate (SC) into the running buffer (20-30 mM 3-(cyclohexylamino)-1-propanesulfonic acid (CAPS) or ammonium acetate, pH 9.5-11) was required to enhance the water solubility of the sample and selectivity of the separation. MEKC proved to be a promising new technique for the separation of the primary oxidation products of lipids giving results comparable to high performance liquid chromatography (HPLC). Partial separation of hydroperoxide isomers was also achieved using nonaqueous CE with methanol-acetonitrile-sodium cholate as running buffer.

Coronary pressure as a determinant of B-type natriuretic peptide gene expression in isolated perfused adult rat heart

The role of coronary flow in the regulation of ventricular B-type natriuretic peptide (BNP) gene expression was studied in isolated perfused rat heart preparation. The increase of coronary flow from 5 ml/min to 20 ml/min for 2 h resulted in a 132+/-6 mm Hg increase in aortic perfusion pressure. The changes in BNP mRNA and immunoreactive BNP (IR-BNP) levels in response to hemodynamic stress were compared to those of c-fos and adrenomedullin (ADM) gene expression. The increase of coronary flow resulted in 1.5-fold increases in the left ventricular BNP mRNA (P < 0.001) and IR-BNP (P < 0.05) levels in 2-month old rats. There was also a 1.5-fold (P < 0.05) increase in ventricular c-fos mRNA levels, whereas ADM mRNA levels decreased by 74% (P < 0.001) in the left ventricle. In 18-month old rats, the increase in coronary flow decreased left and right ventricular BNP mRNA levels by 18% (P < 0.05) and 39% (P < 0.001), respectively. There were no changes in IR-BNP peptide and c-fos mRNA levels, whereas ADM mRNA levels decreased by 46% (P < 0.001) in the left ventricles. The results show that increased aortic perfusion pressure results in differential expression of cardiac genes including up-regulation of ventricular BNP and c-fos gene expression and down-regulation of ADM gene expression. Furthermore, aging seems to elevate the threshold at which hemodynamic stress of the heart results in a response at BNP gene level.

p53 expression in skin carcinogenesis and its relationship to cell proliferation and tumour growth

The immunoreactivity of p53 protein was studied in relation to tumour development, histopathological characteristics, cell proliferation, and basement membrane organisation following the induction of skin carcinogenesis in tumour-sensitive and -resistant mouse strains by ultraviolet (UV) irradiation or 7,12-dimethylbenz(a)anthracene (DMBA). In non-neoplastic skin exposed to UV irradiation or DMBA, p53 immunoreactivity was observed in nearly 50% of the basal layer cells. These cells were morphologically and histochemically indistinguishable from the p53-negative cells, occurring similarly in the tumour-producing and the tumour-negative mouse strains and regardless of subsequent tumour formation. In induced epidermal hyperplasia and in benign tumours, p53-positive and proliferating cells constituted 40-50% of all cells in the basal layer, while superficial cells were p53 negative. In dysplastic epidermis, p53-positive cells and proliferating cells were seen in all cell layers. In the case of squamous cell carcinomas, p53-positive proliferating cells in differentiated neoplasms were localised close to the basement membrane and, more frequently, in border areas showing invasion and basement membrane destruction. In horn cysts, centrally located cells were non-proliferating and p53 negative. In moderately differentiated neoplasms, proliferating cells were located closer to the basement membrane, while p53-positive cells were distributed diffusely in the neoplasm. In poorly differentiated neoplasms, p53-positive cells were more common than proliferating cells and were arranged in a diffuse pattern. The results showed that the number and location of p53-positive cells depended upon histology, with a close relationship to tumour type and degree of malignancy, but not on the mode of induction, nor on the animal strain or the relationship to subsequent tumour formation.