bluuebunny/crossref_metadata_2025 huggingface dataset:
Top-down transformation choice
Authors: Hothorn Torsten
Published: January 2018

Simple models are preferred over complex models, but over-simplistic models could lead to erroneous interpretations. The classical approach is to start with a simple model, whose shortcomings are assessed in residual-based model diagnostics. Eventually, one increases the complexity of this initial overly simple model and obtains a better-fitting model. I illustrate how transformation analysis can be used as an alternative approach to model choice. Instead of adding complexity to simple models, step-wise complexity reduction is used to help identify simpler and better interpretable models. As an example, body mass index (BMI) distributions in Switzerland are modelled by means of transformation models to understand the impact of sex, age, smoking and other lifestyle factors on a person's BMI. In this process, I searched for a compromise between model fit and model interpretability. Special emphasis is given to the understanding of the connections between transformation models of increasing complexity. The models used in this analysis ranged from evergreens, such as the normal linear regression model with constant variance, to novel models with extremely flexible conditional distribution functions, such as transformation trees and transformation forests.
Frailty: A global measure of the multisystem impact of COPD
Authors: Gale Nichola S , Albarrati Ali M , Munnery Margaret M , Hubbard Ruth E , Tal-Singer Ruth , Cockcroft John R , Shale Dennis J
Published: January 2018

Chronic obstructive pulmonary disease (COPD) is a multisystem disease that resembles the accumulation of multiple impairments seen in aging. A comprehensive geriatric assessment (CGA) captures multisystem deficits, from which a frailty index (FI) can be derived. We hypothesized that patients with COPD would be frailer than a comparator group free from respiratory disease. In this cross-sectional analysis, the CGA questionnaire was completed and used to derive an FI in 520 patients diagnosed with COPD and 150 comparators. All subjects were assessed for lung function, body composition, 6-minute walking distance (6MWD), and handgrip strength. Patients completed validated questionnaires on health-related quality of life and respiratory symptoms. Patients and comparators were similar in age, gender, and body mass index, but patients had a greater mean ± SD FI 0.16 ± 0.08 than comparators 0.05 ± 0.03. In patients, a stepwise linear regression 6MWD ( β = −0.43), number of comorbidities ( β = −0.38), handgrip ( β = −0.11), and number of exacerbations ( β = 0.11) were predictors of frailty (all p < 0.01). This large study suggests patients with COPD are frailer than comparators. The FI derived from the CGA captures the deterioration of multiple systems in COPD and provides an overview of impairments, which may identify individuals at increased risk of morbidity and mortality in COPD.
Employee Responses to Empowering Leadership: A Meta-Analysis
Authors: Kim Minseo , Beehr Terry A. , Prewett Matthew S.
Published: January 2018

A recent and growing number of studies examined how empowering leadership influences employee outcomes. At the individual level, we meta-analyzed 55 independent samples to determine the association between empowering leader behaviors and subordinates’ responses. Results confirmed the positive links of empowering leadership with evaluations of the leader as well as with employee motivation and resources, attitudes, and performance; the strongest correlation was between empowering leadership and attitudes toward the leader (ρ = .59), whereas the weakest correlation was for empowering leadership with behavioral and performance outcomes (ρ = .31). However, the relationship of empowering leadership with subordinates’ emotions was not significant. Examination of potential moderators, including rating sources, nationality of sample, gender, and industry, did not explain much of the heterogeneity in the results. In sum, findings highlight the potential benefit of empowering leadership for individual and organizational outcomes. Thus, more knowledge about what causes empowering leadership could be useful.
Let’s Look at This Another Way: How Supervisors Can Help Subordinates Manage the Threat of Relationship Conflict
Authors: Thiel Chase E. , Griffith Jennifer A. , Hardy Jay H. , Peterson David R. , Connelly Shane
Published: January 2018

Despite decades of scholarly and practitioner attention on conflict management, few studies have addressed the important role that supervisors play in managing relationship conflict (RC). The current research addresses this gap by investigating the use of supervisory interpersonal emotion management in helping subordinates manage perceptions of RC. Examining RC through a threat framework, we propose that when individuals perceive RC in their workgroup, they are less likely to identify with their group and more likely to withdraw from the group in ways that affect critical team processes, both of which have performance implications. Furthermore, we propose that supervisors can mitigate the consequences of perceiving RC by encouraging subordinates to reappraise past negative events that contribute to such perceptions. Using a field sample of 917 employees, we tested and found support for these predictions. This research primarily has implications for conflict theory, RC management theory, and RC management practices.
A novel forestry chassis with an articulated body with 3 degreesof freedom and installed luffingwheel-legs
Authors: Zhu Yue , Kan Jiangming , Li Wenbin , Kang Feng
Published: January 2018

One of the challenging problems in the forest industry is to develop a chassis that is well-adapted to the complex terrain conditions in the forest. In this article, a novel forestry chassis with an articulated body with 3 degrees of freedom and installed luffing wheel-legs (FC-3DOF&LW) is proposed, and the mechanical model of the luffing wheel-leg is built. Based on the mechanical model, the hydraulic cylinder velocity that involves the wheel-leg luffing is calculated. The process of surmounting the obstacle is presented by multi-body dynamics simulation. To demonstrate the improvement of ride comfort, the other simulation of the chassis with an articulated body with 3 degrees of freedom (FC-3DOF) is contrasted in multi-dynamics software. The final result shows that curves of barycenter displacement for FC-3DOF&LW with the front and rear frames are well matched when the front frame surmounts the obstacle; in particular, the barycenter displacement is almost stable when the rear frame surmounts the obstacle. The maximum rotated angle of the articulated joint reaches almost 37° without the luffing wheel-leg, whereas it is only 4° with FC-3DOF&LW, a decrease of 89.1%. Moreover, the acceleration trend for FC-3DOF&LW is more stable than that for FC-3DOF.
Simulating eddy current sensor outputs for blade tip timing
Authors: Jamia Nidhal , Friswell Michael I , El-Borgi Sami , Fernandes Ralston
Published: January 2018

Blade tip timing is a contactless method used to monitor the vibration of blades in rotating machinery. Blade vibration and clearance are important diagnostic features for condition monitoring, including the detection of blade cracks. Eddy current sensors are a practical choice for blade tip timing and have been used extensively. As the data requirements from the timing measurement become more stringent and the systems become more complicated, including the use of multiple sensors, the ability to fully understand and optimize the measurement system becomes more important. This requires detailed modeling of eddy current sensors in the blade tip timing application; the current approaches often rely on experimental trials. Existing simulations for eddy current sensors have not considered the particular case of a blade rotating past the sensor. Hence, the novel aspect of this article is the development of a detailed quasi-static finite element model of the electro-magnetic field to simulate the integrated measured output of the sensor. This model is demonstrated by simulating the effect of tip clearance, blade geometry, and blade velocity on the output of the eddy current sensor. This allows an understanding of the sources of error in the blade time of arrival estimate and hence insight into the accuracy of the blade vibration measurement.
Flow field and species concentration measurements in the primary zone of an aero-engine combustion chamber
Authors: Xiao Yinli , Wang Zupeng , Lai Zhengxin , Chen Kefei , Song Wenyan
Published: January 2018

The principal features of primary zone determine the performance parameters of the whole combustion chamber, such as the pollutant emissions and combustion efficiency. In this work, flow field and major species concentration measurements are conducted in the primary zone of an aero-engine combustion chamber. The operating conditions such as air inlet temperature, chamber pressure, and air-to-fuel ratio are chosen to replicate the realistic operating conditions. The velocity field and streamlines are obtained by particle imaging velocimetry technology. The concentrations of major species are acquired by a spontaneous Raman scattering system. This article validates the feasibility of two laser diagnostic measurement techniques and presents the initial results under realistic aero-engine conditions.
An experimental study on torque characteristics of magnetorheological brake with modified magnetic core shape
Authors: Sohn Jung Woo , Gang Han Gyeol , Choi Seung-Bok
Published: January 2018

In this article, a new type of magnetorheological brake is designed and its torque characteristics are investigated experimentally. The proposed magnetorheological brake consists of an outer housing, a rotating drum, magnetorheological fluid, and a copper wire coiled magnetic core to generate a magnetic field. At first, the structural configurations of the magnetorheological brakes are presented with conventional and modified magnetic core shape. To achieve enhanced braking torque under limited small size, a modified magnetic core shape is adopted in the proposed magnetorheological brake. After manufacturing the magnetorheological brakes and measurement of braking torque, it is verified that the proposed magnetorheological brake with modified magnetic core shape has improved braking torque compared to conventional-type magnetorheological brake. For the actuator application, the dynamic characteristics, such as rising time, settling time, and falling time, of the proposed magnetorheological brake is also experimentally evaluated by observing the step response. In addition, the torque tracking control performance is also investigated by adopting fuzzy–proportional–integral–derivative control algorithm for desired input of sinusoidal and multi-magnitude step input. It is demonstrated that the proposed magnetorheological brake can be successfully used as an actuator with limited small size.
Prognostic Value of Cytokeratin 19 Fragment (CYFRA 21–1) and Cytokeratin-Positive Cells in Bone Marrow Samples of Breast Cancer Patients
Authors: Pierga J.-Y. , Deneux L. , Bonneton C. , Vincent-Salomon A. , Nos C. , Anract P. , Magdelénat H. , Pouillart P. , Thiery J.-P.
Published: January 2018

The aim of this study was to investigate the relationship between the detection of micrometastatic cells by immunocytochemistry (ICC) with an anticytokeratin antibody and cytokeratin fragment (CYFRA 21–1) expression detected by an immunofluorescent assay in bone marrow of breast cancer patients. Micrometastatic CK+ cells were screened with a pancytokeratin antibody A45 B/B3 from bone marrow aspiration samples of 102 breast cancer patients (65 primary tumors, 10 local recurrences and 27 distant metastases). CYFRA 21-1 levels were assessed in bone marrow supernatant of these patients before collection of the mononucleated interface cells on a Ficoll-Hypaque density gradient and in 20 control patients. CYFRA 21-1 and CK+ cell detection by ICC were both correlated with clinical stage. CYFRA 21-1 was significantly elevated in patients with micrometastatic disease detected by ICC: 4.77 ng/mL (± 10.87 SD) versus 1.00 ng/mL (± 1.36 SD) in patients with negative ICC (p=0.01). In univariate analysis, a CYFRA 21-1 value ≥1 ng/mL and the presence of CK+ cells were associated with a poorer survival for patients with stage I to III breast cancer (n=65). On multivariate analysis, only pathological nodal status and presence of CK+ cells in bone marrow were independent prognostic factors for overall survival. In conclusion, in this series CYFRA 21-1 was correlated with detection of CK+ cells by ICC in bone marrow, but cannot replace ICC. The presence of CK+ cells in bone marrow remains a strong independent prognostic factor in primary breast cancer.
Prognostic Significance of Elevated Endothelin-1 Levels in Patients with Colorectal Cancer
Authors: Arun C. , London N.J.M. , Hemingway D.M.
Published: January 2018

Background

Prognostic factors from clinical, laboratory and pathological data of patients with colorectal cancer are essential to identify high-risk groups to whom beneficial adjuvant therapy could be given. Endothelin-1, a growth factor, has been associated with the development and spread of solid tumours. This prospective study was performed to determine whether preoperative plasma big ET-1 levels might be useful as a prognostic indicator in patients with colorectal carcinoma.

Method

Sixty-five consecutive patients with colorectal cancer confirmed by biopsy were included prospectively into this study over a 12-month period. Plasma samples from a peripheral vein were obtained prior to surgery. Univariate analysis of survival using age (< or > 70 years), sex, Dukes’ stage (A&B versus C), tumour size (< or > 50 mm), vascular invasion and plasma big ET-1 levels was performed and significant factors were then analysed with the Cox regression model.

Results

Three variables, age, Dukes’ tumour stage and plasma big ET-1 levels, were found to have prognostic significance (p<0.05). Factors associated with a poorer prognosis were age >70 years (p=0.02), Dukes’ C tumours (p=0.04) and plasma big ET-1 levels >4.2 pg/mL (p=0.02). The Cox regression model identified the same three variables as having independent prognostic value for overall survival.

Conclusion

Preoperative plasma big ET-1 levels may be useful in predicting overall survival in patients with colorectal cancer. Plasma big ET-1 levels may be useful in the selection of high-risk lymph node-negative patients with colorectal cancer for adjuvant therapy.
Clinical Significance of Preoperative Serum Sialic Acid Levels in Colorectal Cancer: Utility in the Detection of Patients at High Risk of Tumor Recurrence
Authors: Feijoo-Carnero C. , Rodríguez-Berrocal F.J. , de la Cadena M. Pez , Ayude D. , de Carlos A. , Martínez-Zorzano V.S.
Published: January 2018

This study was conducted to evaluate the significance of preoperative serum sialic acid levels in the diagnosis and prognosis of colorectal cancer (CRC). Total sialic acid (TSA) was determined by the thiobarbituric acid method and normalized to total protein (TP). A postoperative follow-up of CRC patients classified as Dukes’ stages A, B or C was performed and survival analysis was carried out to evaluate the impact of sialic acid levels on tumor recurrence. Our diagnostic studies indicate that TSA/TP is a better marker than either TSA or carcinoembryonic antigen (CEA), especially for the detection of CRC patients at an early stage. At a cutoff of 30.90 nmol/mg of protein, TSA/TP showed a sensitivity of 85% with a specificity of 97% to discriminate CRC patients from healthy donors. In survival analysis, both TSA and TSA/TP were found to be significant prognostic factors for tumor recurrence in CRC. Furthermore, TSA/TP could distinguish patients at high risk of recurrence within Dukes’ stage B and in multivariate analysis it was identified as the best independent prognostic factor. According to our results, preoperative serum TSA/TP content could supply additional information to that provided by Dukes’ stage about the prognosis of CRC patients.
Clinical Significance of Serum Gastrin Levels in Patients with Colorectal Cancer
Authors: Tocchi A. , Mazzoni G. , Puma F. , Miccini M. , Daddi G. , Bettelli E. , Cassini D. , Brozzetti S.
Published: January 2018

Aims

An association between elevated serum gastrin levels and the presence of human colorectal cancer has been reported, and gastrin has been shown to stimulate the growth of experimentally induced colon neoplasia. The aim of this study was to determine the preoperative and postoperative concentrations of serum gastrin in 53 patients with colorectal cancer and to assess the correlation between gastrin levels and tumor characteristics and prognosis.

Materials and Methods

A prospective study was performed over a six-year period during which 53 patients received potentially curative surgery for colorectal cancer. The prognostic variables used for the analysis included age, sex, tumor site, stage and degree of differentiation, preoperative and postoperative serum values of carcinoembryonic antigen (CEA) and gastrin, cancer-related mortality, and survival. CEA and gastrin serum values were determined using radioimmunological methods. Follow-up was carried out with clinical and radiological tests.

Results

The mean preoperative gastrin concentration was 51.2 ± 27.4 pg/mL (range 12–146). Significantly increased serum gastrin concentrations, which returned to normal after surgery, were detected only in patients with well-differentiated cancer (74.2 ± 28.3 pg/mL; moderately differentiated, 52.1 ± 23.8; poorly differentiated, 29.9 ± 12.3, p=0.02). The prognosis was unrelated to serum gastrin level; instead, tumor stage, preoperative CEA value, and degree of differentiation affected patient survival.

Conclusions

This study showed that the serum gastrin concentration is not an appropriate clinical oncogenic factor. Although occurring only in well-differentiated tumors, serum gastrin is unrelated to the prognosis of patients with colorectal cancer.
Frequent Detection and Immunophenotyping of Prostate-Derived Cell Clusters in the Peripheral Blood of Prostate Cancer Patients
Authors: Schmidt H. , De Angelis G. , Bettendorf O. , Eltze E. , Semjonow A. , Knichwitz G. , Brandt B.
Published: January 2018

Background

Recent scientific studies have failed to determine parameters for the assessment of prostate cancer aggressiveness. The present study deals with the detection of blood-borne cancer cells based on polymerase chain reaction (PCR) and cell enrichment methods. The contradictory results reported in the literature have called into question the clinical usefulness of this diagnostic method in the preoperative staging of clinically localized prostate cancer.

Methods

We established a combined method of density gradient centrifugation and immunomagnetic separation using epithelium-specific antibodies, i.e. cytokeratins, to isolate prostate-derived circulating cells from the peripheral blood of patients with prostate cancer. Isolated cells were characterized by DNA staining and immunocytochemistry using antibodies for the detection of prostate-specific antigen (PSA), proliferation-associated proteins (MIB-1, H1 and H3) and apoptosis-associated proteins (M30, c-FasR).

Results

We applied these methods to 68 prostate cancer patients and were able to isolate cell clusters in 98%. Immunophenotypic and morphological characterization of PSA-positive prostate-derived cell clusters found in the peripheral blood of prostate cancer patients showed two main populations: 1) in 35% of the investigated prostate cancer patients we detected rounded cell aggregates of probable cancer cells expressing proliferation-associated proteins and lacking apoptosis-associated protein expression; 2) in all cases there was a high frequency of circulating dysmorphic cell clusters positive for apoptosis-associated protein expression.

Conclusion

Our results demonstrate the existence of at least two different types of blood-borne prostate-derived circulating cell clusters. Of these, only the less frequent, round, small cell clusters harbor features that are probably necessary for the cells to survive for metastatic spread.
TPS and CA 19-9 Measurements in the Follow-Up of Patients with Pancreatic Cancer and Chronic Pancreatitis
Authors: Slesak B. , Harlozinska-Szmyrka A. , Knast W. , Sedlaczek P. , Einarsson R. , van Dalen A.
Published: January 2018

The aim of this study was to assess the value of TPS and CA 19–9 in a long-term follow-up analysis of 11 patients with chronic pancreatitis (CP) and 15 patients with pancreatic cancer (PC). In all monitored patients with chronic pancreatitis the initial TPS level was below 200 U/L, whereas CA 19–9 was elevated in two of them. In one patient a dramatic increase in the TPS concentration (820 U/L) was measured at the last follow-up visit (after 8.6 months), which led to the detection of PC. In all patients with PC the preoperative TPS level exceeded 200 U/L, whereas CA 19–9 was elevated in only nine patients. After the Kausch-Whipple operation 11 patients showed no evidence of disease and in eight of these patients both TPS and CA 19–9 were within the reference range; however, in three patients liver metastases were detected after 8–24 months from the last tumor marker measurement. In four of the 15 patients both markers were elevated at the end of the follow-up period and distant metastases were clinically confirmed. Our results indicate that in patients with CP and PC undergoing long-term follow-up, TPS reflects the clinical status of patients more accurately than CA 19–9.
Comparison of Expression of Cathepsins B and L and MMP2 in Endothelial Cells and in Capillary Sprouting in Collagen Gel
Authors: Caserman S. , Lah T.T.
Published: January 2018

The lysosomal cysteine proteinases cathepsins B and L are known to play an important role in the invasive growth of tumor cells, but their association with angiogenesis has been less well studied. The aim of this study was to determine the possible role of endothelial cell-associated cathepsins B and L in induced capillary growth in the aorta ring model of angiogenesis. Specific inhibitors of cysteine proteinases did not inhibit capillary growth in aorta ring culture and only slightly inhibited the degradation of surrounding collagen. In contrast, strong inhibition of both processes by the matrix metalloproteinase inhibitor BB-94 was observed, indicating the importance of endogenous MMP production in angiogenesis. In support of this finding, we demonstrated a significant increase in endogenous endothelial mRNA of MMP2, but not of cathepsins B and L, in proliferating primary human dermal microvascular endothelial cells (HMVEC-d) in culture. However, MMP2 mRNA expression was increased only when the cells were embedded in collagen but not when they were grown on plastic, regardless of the addition of the growth factors VEGF or bFGF. Moreover, on plastic the impairment of MMP2 induction by growth factors was observed. The differential effect of growth factors implies the crosstalk with integrin signaling as a consequence of binding to the different matrix. This study suggests that endothelial cell-associated cathepsins B and L are not involved in the invasive growth of capillaries from existing blood vessels and that the presence of collagen is necessary for MMP2 expression in endothelial cells.
Efficacy of Cancer Chemotherapy in Relation to the Pretreatment Number of Lymphocytes in Patients with Metastatic Solid Tumors
Authors: Lissoni P. , Brivio F. , Fumagalli L. , Messina G. , Ghezzi V. , Frontini L. , Giani L. , Vaghi M. , Ardizzoia A. , Gardani G.S.
Published: January 2018

The evidence of lymphocytopenia has been demonstrated to predict a poor prognosis in terms of survival in advanced cancer patients. This finding is not surprising because of the fundamental role of lymphocytes in mediating tumor cell destruction. Despite the importance of lymphocytes in the pathogenesis of cancer, there are only few data about the profile and the function of lymphocytes during the various antitumor therapies, and in particular the relation between lymphocyte pretreatment number and response to chemotherapy remains to be established. The present study was performed to evaluate whether the evidence of lymphocytopenia before the onset of treatment may influence the efficacy of chemotherapy in metastatic cancer patients affected by the most frequent tumor types. The study included 183 patients (lung cancer: 89; colorectal cancer: 63; breast cancer: 31), 95 of whom had been previously treated with chemotherapy. The chemotherapeutic regimens consisted of oxaliplatin plus 5-fluorouracil and folates in untreated colorectal cancer, weekly irinotecan in pretreated colorectal cancer, cisplatin plus gemcitabine or etoposide in untreated lung cancer, weekly vinorelbine in pretreated lung cancer, and taxotere in breast cancer patients who had been previously treated with anthracyclines. Lymphocyte count was considered to be abnormally low for values below 1500/mm3. Lymphocytopenia was found in 79/183 (43%) patients, without any significant differences in relation to tumor histology. A complete response (CR) was achieved in 6/104 patients with a normal lymphocyte count and in none of the 79 lymphocytopenic patients. A partial response (PR) was obtained in 39 patients with a normal lymphocyte count and in only eight patients with a low lymphocyte count prior to therapy. Therefore, irrespective of the type of chemotherapy, the objective tumor response rate (CR + PR) in lymphocytopenic patients was significantly lower than in patients with normal pretreatment lymphocyte counts (8/79 vs 45/104; p<0. 001). This study shows that the evidence of lymphocytopenia prior to chemotherapy is associated with a lower efficacy of treatment in terms of objective tumor regression rates in patients with metastatic solid tumors, and suggests that the action of chemotherapy may depend at least in part on an interaction with the antitumor immunity. Pretreatment lymphocyte count may represent a new, simple biological marker to be taken into consideration by oncologists in the chemotherapeutic treatment of metastatic cancer.
Statistical Diagnostics Emerging from External Quality Control of Real-Time PCR
Authors: Marubini E. , Verderio P. , Raggi C. Casini , Pazzagli M. , Orlando C.
Published: January 2018

Besides the application of conventional qualitative PCR as a valuable tool to enrich or identify specific sequences of nucleic acids, a new revolutionary technique for quantitative PCR determination has been introduced recently. It is based on real-time detection of PCR products revealed as a homogeneous accumulating signal generated by specific dyes. However, as far as we know, the influence of the variability of this technique on the reliability of the quantitative assay has not been thoroughly investigated. A national program of external quality assurance (EQA) for real-time PCR determination involving 42 Italian laboratories has been developed to assess the analytical performance of real-time PCR procedures. Participants were asked to perform a conventional experiment based on the use of an external reference curve (standard curve) for real-time detection of three cDNA samples with different concentrations of a specific target. In this paper the main analytical features of the standard curve have been investigated in an attempt to produce statistical diagnostics emerging from external quality control. Specific control charts were drawn to help biochemists take technical decisions aimed at improving the performance of their laboratories. Overall, our results indicated a subset of seven laboratories whose performance appeared to be markedly outside the limits for at least one of the standard curve features investigated. Our findings suggest the usefulness of the approach presented here for monitoring the heterogeneity of results produced by different laboratories and for selecting those laboratories that need technical advice on their performance.
Interobserver Reproducibility of Immunohistochemical Her-2/Neu Evaluation in Human Breast Cancer: The Real-World Experience
Authors:   Italian Network for Quality Assurance of Tumor Biomarkers (INQAT) Group, Paradiso A. , Marubini E. , Verderio P. , Cortese M.E. , De Paola F. , Silvestrini R. , Simone G. , Marzullo F. , Menard S. , Tagliabue E. , Tomasich G. , Mottolese M. , Querzoli P. , Bevilacqua G. , Campani D. , Granato A. , Marinaro E. , Folicaldi S. , Naldi N. , Ludovini V. , Maioli P. , Bernardi L.
Published: January 2018

In spite of the large number of studies on technical problems affecting the interlaboratory reproducibility of IHC HER-2/neu determination, only little is known about factors limiting the intra- and interobserver reproducibility in the actual practice of HER-2/neu expression analysis. The aim of the present INQAT study was to evaluate the intra- and interobserver reproducibility of IHC HER-2 analysis among pathologists routinely working in Italian laboratories. Twenty immunostained slides were distributed to 12 pathologists who had to report, for each slide, the semiquantitative analysis of the percentage of immunopositive cells and the qualitative evaluation of the intensity of membrane staining. The intra- and interobserver reproducibility as well as the reproducibility between each laboratory and the reference values were quantified adopting an approach based on computation of the weighted kappa statistic (Kw). Additionally, in order to evaluate the contribution of each category to the overall agreement, the kappa category-specific statistics (Kcs) were estimated for both classification criteria by jointly considering all the participating laboratories. The intraobserver analyses showed a satisfactory level of reproducibility for both the percentage of positive cells (median Kw, 0.94; range: 0.80–0.96) and membrane staining (median Kw, 0.86; range: 0.78–0.96). Similarly, a fairly good level of reproducibility for the percentage of cells (median Kw, 0.89; range, 0.73–0.96) and the intensity of membrane staining (median Kw, 0.84; range, 0.72–0.92) were observed from comparisons with reference values. When all possible pairwise comparisons were performed, a satisfactory level of interobserver reproducibility was found for most laboratories. Kw values varied between 0.51 and 0.98 (median Kw, 0.80) and between 0.61 and 0.94 (median Kw, 0.81) for semiquantitative and qualitative measurements, respectively. Analysis of the contribution of the extreme categories to the overall agreement showed a substantial or almost perfect agreement for both classification criteria. Conversely, the contribution of intermediate categories appeared to be scarce or slight for the percentage of immunostained cells and slight or fair for the intensity of membrane staining. We conclude that, overall, the interobserver reproducibility in IHC analysis of HER-2/neu expression is satisfactory, although classification of the intermediate categories is problematic, both with regard to the percentage of immunostained cells and the intensity of membrane staining.
Mismatch Repair Protein MSH2 Expression and Prognosis of Colorectal Cancer Patients
Authors: Bernardo C.G. , Gonzílez J.J. , Sanz L. , Barbón E. , Noval J.G. , Fresno M.F. , Aza J.
Published: January 2018

Introduction and aims

The role of genetic factors in the etiology and prognosis of patients with sporadic colorectal cancer is controversial. We have therefore investigated the biological and clinicopathological influence of immunohistochemical MSH2 expression in colorectal cancer.

Patients and methods

A total of 49 consecutive patients with unselected colorectal cancer operated on in our unit were included in the study. All tumors were resected and tumor specimens were evaluated for MSH2 expression. Clinicopathological data and patient survival were correlated with MSH2 staining. Uni- and multivariate analyses were performed. The minimum follow-up period was five years.

Results

Curative resection was performed in 34 patients (64.9%), 14 of whom subsequently relapsed. At the end of the overall follow-up 25 (51%) patients had died, 21 of cancer-related causes. Twenty-eight patients (57.1%) were negative for MSH2 staining. Only vascular invasion was significantly correlated with MSH2 expression (lower median values; p=0.04). The overall median survival was 47.9 months (95% CI=27–86.6%). Multivariate analysis of variables in relation to survival showed that T stage (p=0.001), N stage (p<0.001) and MSH2 expression (p=0.01) were independent factors for survival.

Conclusions

Reduced MSH2 expression is frequent in unselected colorectal cancer patients. Only vascular invasion was correlated with MSH2 expression in this study. Survival was related to TN stage and MSH2 staining.
PAP Modulations in Daudi Cells and Molt-3 Cells Treated with Etoposide are Mutually Associated with Morphological Evidence of Apoptosis
Authors: Thomadaki E. , Havredaki M. , Tsiapalis C.M.
Published: January 2018

Daudi (B-cell line) and Molt-3 (T-cell line) cells provide a model for the study of apoptosis, the induction of which is often accompanied by concominant modulations of proteins involved in mRNA maturation. One of these proteins is poly(A) polymerase (PAP), which is responsible for mRNA cleavage and polyadenylation. A number of recent reports also suggest involvement of mRNA maturation and stability in the induction of specific pathways of cell apoptosis. In this study we identified PAP activity levels and isoform modulations in two different cell lines (Daudi and Molt-3) and related them to DNA fragmentation (a hallmark of apoptosis) and cell cycle phase specificity in terms of the temporal sequence of events and the time that elapsed between administration of the apoptosis inducer (the widely used anticancer drug etoposide) and the observed effects. Treatment of both cell lines with 20 μg/mL etoposide induced apoptosis after four hours in Molt-3 cells and only after 24 hours in Daudi cells, as revealed by two independent methods. In Daudi cells the PAP activity levels and isoforms were downregulated prior to ΔΨm reduction, DNA fragmentation and the morphological changes of the nucleus, whereas in Molt-3 cells no PAP activity and isoform modulations were observed prior to the early hallmarks of apoptosis.
Antibody Response after Vaccination with Antigen-Pulsed Dendritic Cells
Authors: Battaini F. , Besusso D. , Sfondrini L. , Rossini A. , Morelli D. , Tagliabue E. , Menard S. , Balsari A.
Published: January 2018

Dendritic cells (DCs) are the most potent antigen-presenting cells of the immune system capable of initiating immune responses to antigens. It is also well documented that cancer patients often experience anergy against tumor antigens. In this study we selected the best protocol for inducing the production of antibodies against the HER2 oncoprotein using DCs to overcome anergy. Murine DCs were pulsed in vitro, using different protocols, with recombinant HER2 fused to a human Fc (in order to improve DC antigen uptake) and were used to vaccinate mice. The obtained results indicate that antigen-pulsed DCs can induce an antibody response and that adding CpG after antigen pulsing greatly increases anti-HER2 antibody production.
Shift in the Balance between Circulating Thrombospondin-1 and Vascular Endothelial Growth Factor in Cancer Patients: Relationship to Platelet α-Granule Content and Primary Activation
Authors: Gonzalez F.J. , Rueda A. , Sevilla I. , Alonso L. , Villarreal V. , Torres E. , Alba E.
Published: January 2018

Tumoral angiogenesis is regulated by the balance between factors that activate and inhibit angiogenesis. Elevated levels of activators have been associated with a poor prognosis in cancer patients, but little is known about the net balance between circulating activators and inhibitors in these patients. This study was designed to determine whether the balance between circulating concentrations of the angiogenesis inhibitor TSP-1 and the activator VEGF differs from that in healthy persons, and to shed light on the possible role of platelets in this balance. Twenty-five cancer patients and 18 healthy subjects were included. Serum and plasma concentrations of VEGF, TSP-1 and PF4 were measured by ELISA. Our results showed that in healthy subjects the balance between the TSP-1 and VEGF concentrations in serum and in serum minus plasma was twice to three times as high as in cancer patients (p<0.05). The theoretical TSP-1 content per platelet was greater in healthy subjects than in patients (94 vs. 53.6 ng/mL, p<0.05), and platelet activation (determined indirectly as the plasma concentration of PF4) was greater in cancer patients (129 vs. 48 IU/mL, p<0.01). Platelet activation correlated significantly with serum concentration of TSP-1 (r=0.470, p=0.018) and showed a tendency toward correlation with plasma concentration of TSP-1 (r=0.382, p=0.059). Our findings show that the circulating TSP-1/VEGF balance is diminished in cancer patients. Platelet activation may play an important role in this decrease and may ultimately lead to increased angiogenic activity in these patients.
Expression and Clinical Significance of Pepsinogen C in Uveal Melanomas
Authors: Alvarez M.L. , Gonzílez L.O. , Barbón J.J. , Astudillo A. , Vizoso F.J.
Published: January 2018

Purpose

we investigated by immunohistochemistry the pepsinogen C (pepC) expression in uveal melanomas and analyzed the possible relationship to clinicopathological parameters and prognostic significance.

Methods

We studied 22 patients who had undergone enucleation of the eyeball or local tumor resection for uveal melanoma. The specimens were immunostained for pepC on formalin-fixed, paraffin-embedded sections. Sex, age, tumor location, histological type, local invasion, postoperative treatment and metastasis were evaluated.

Results

Eleven tumors (50%) were positive for pepsinogen C. The percentage of pepC-positive tumors was significantly higher in uveal melanomas with scleral invasion than in those without scleral invasion (p<0.01). PepC expression was significantly associated with a shortened overall survival (p<0.05).

Conclusions

Our results show that pepsinogen C may be expressed by uveal melanoma and suggest that this protein could be considered as a new, unfavorable prognostic factor in these tumors.
Vitamin D Receptor Polymorphisms and Prostate Cancer Risk in Brazilian Men
Authors: Maistro S. , Snitcovsky I. , Sarkis A.S. , da Silva I.A. , Brentani M.M.
Published: January 2018

Vitamin D seems to be an important determinant of prostate cancer risk and inherited polymorphisms in the 3′untranslated region of the vitamin D receptor (VDR) gene have been associated with the risk and progression of prostate cancer in some populations. We therefore studied VDR gene polymorphisms, as detected by ApaI and TaqI restriction fragments, in multiethnic Brazilian men (165 patients and 200 controls) for association with prostate cancer risk and parameters of disease severity (serum PSA, Gleason score and tumor stage). No statistical correlations were found. The unique ethnical background of Brazilian subjects, characterized by an extensive racial mixture of European, African-American and Native American, might have blunted any ethnic-specific significance of VDR polymorphisms. Further investigations of the associations between VDR and other genetic or environmental factors are warranted.
Endothelin-1 is a Novel Prognostic Factor in Non-Small Cell Lung Cancer
Authors: Arun C. , DeCatris M. , Hemingway D.M. , London N.J.M. , O'Byrne K.J.
Published: January 2018

Endothelin-1 (ET-1) is a potent vasoactive peptide and a hypoxia-inducible angiogenic growth factor associated with the development and growth of solid tumours. This study evaluated the expression of big endothelin-1 (big ET-1), a stable precursor of ET-1, and ET-1 in non-small cell lung cancer (NSCLC). Big ET-1 expression was evaluated in paraffin-embedded tissue sections from 10 NSCLC tumours using immunohistochemistry and in situ hybridisation. The production of big ET-1 and ET-1 was studied in six established NSCLC cell lines. The plasma concentrations of big ET-1 were measured in 30 patients with proven NSCLC prior to chemotherapy by means of a sandwich enzyme-linked immunoassay and compared to levels in 20 normal controls. Big ET-1 immunostaining was detected in the cancer cells of all tumours studied. Using in situ hybridisation, tumour cell big ET-1 mRNA expression was demonstrated in all samples. All six NSCLC cell lines expressed ET-1, with big ET-1 being detected in three. The median big ET-1 plasma level in patients with NSCLC was 5.4 pg/mL (range 0–22.7 pg/mL) and was significantly elevated compared to median big ET-1 plasma levels in controls, 2.1 pg/mL (1.2–13.4 pg/mL) (p=0.0001). Furthermore, patients with plasma big ET-1 levels above the normal range (upper tertile) had a worse outcome (p=0.01). In conclusion, big ET-1/ET-1 is expressed by resected NSCLC specimens and tumour cell lines. Plasma big ET-1 levels are elevated in NSCLC patients compared to controls with levels >7.8 pg/mL being associated with a worse outcome. The development of selective ET-1 antagonists such as Atrasentan indicates that ET-1 may be a therapeutic target in NSCLC.
Vascular Endothelial Growth Factor (Vegf) and Other Common Tissue Prognostic Indicators in Breast Cancer: A Case-Control Study
Authors: Nicolini A. , Campani D. , Miccoli P. , Spinelli C. , Carpi A. , Menicagli M. , Ferrari P. , Gadducci G. , Rossi G. , Fini M. , Giavaresi G. , Bonazzi V. , Giardino R.
Published: January 2018

VEGF is a specific mitogen and survival factor for endothelial cells and a key promoter of angiogenesis in physiological and pathological conditions. Nevertheless, VEGF tissue evaluation in cancer patients as a prognostic factor compared to the conventional histological and biological parameters is still controversial. In this case-control study, tissue VEGF was retrospectively determined by immunohistochemistry and related to T, N, ER, PgR, c-erbB-2, p53, MIB-1 and cyclin D1 in 129 breast cancer patients. Seventy-four of these patients had developed distant metastases postoperatively. The remaining 55 patients had remained disease-free >10 years after surgery. In 17 (13%) of the 129 patients (six with distant metastases and eleven disease-free) tissue and plasma VEGF were concomitantly evaluated. In univariate analysis no significant differences in VEGF and tumor size were found between metastatic and disease-free patients, whereas there were significant differences in N, ER, PgR, c-erbB-2, p53, MIB-1 and cyclin D1 (p ranging from 0.001 to 0.0001). In multivariate analysis VEGF showed less significance than N, ER, c-erbB-2, MIB-1 and cyclin D1 (p=0.012, p=0.007, p=0.005, p=0.005, p=0.002 and p=0.001, respectively). VEGF was a significant unfavorable prognostic indicator only in the N+ subset (p=0.015), while ER (p=0.05 and p=0.021) and MIB-1 (p=0.031 and p=0.022) were significant in both the N+ and N– subgroups. In multivariate analysis in the 74 metastatic cases VEGF did not show any significance in relation to disease-free interval and overall survival from the time of mastectomy and from the time of relapse, whereas N and PgR did (p ranging from 0.018 to 0.001). In conclusion, tissue VEGF does not seem a suitable candidate to replace conventional histological and other common biological prognostic factors in breast cancer.
The Prognostic Value of Vascular Endothelial Growth Factor, Urokinase Plasminogen Activator and Plasminogen Activator Inhibitor-1 in Node-Negative Breast Cancer
Authors: Meo S. , Dittadi R. , Peloso L. , Gion M.
Published: January 2018

The vascular endothelial growth factor (VEGF) and the plasminogen activator system play an essential role in solid tumor angiogenesis and in tumor invasion and metastasis. In the present study we investigated the relationship between patient outcome and levels of VEGF, urokinase plasminogen activator (uPA) and plasminogen activator inhibitor-1 (PAI-1) in tumor cytosols of 196 node-negative primary invasive breast cancer patients who did not receive any adjuvant therapy. The median follow-up was 65 months. VEGF, uPA and PAI-1 were measured by commercially available enzyme-linked immunosorbent assays. Cox's univariate analysis showed that pT (p=0.0007), uPA (p=0.0156) and PAI-1 (p=0.0015) had a significant impact on relapse-free survival, whereas VEGF did not have any prognostic value (p=0.18). Bivariate analysis showed significant interactions between uPA and PAI-1 (p=0.0035) and between VEGF and PAI-1 (p=0.006). Our study confirms that uPA and PAI-1 cytosol levels can be considered as prognostic factors for relapse-free survival in node-negative breast cancer. Moreover, the interaction between VEGF and PAI-1 warrants further investigation into the relationship between the biomarkers of angiogenesis and those of the protease cascade.
Accuracy and Clinical Correlates of Two Different Methods for Chromogranin A Assay in Neuroendocrine Tumors
Authors: Ferrari L. , Seregni E. , Lucignani G. , Bajetta E. , Martinetti A. , Aliberti G. , Pallotti F. , Procopio G. , Torre S. Della , Luksch R. , Bombardieri E.
Published: January 2018

Measurement of chromogranin A (CgA) plays a major role in the management of neuroendocrine tumors (NET); however, reliable assaying of CgA is made difficult by the rapid hydrolysis following its release into the bloodstream. This study was aimed at the assessment of two assays for CgA in NET patients. CgA was measured in 93 patients by means of an enzyme-linked immunosorbent assay (ELISA) and an immunoradiometric assay (IRMA). The specificity and sensitivity of CgA were evaluated in relation to tumor histology. The clinical accuracy of the two assays was evaluated by receiver-operating characteristic (ROC) curve analysis. Regression analysis demonstrated different immunoreactivity for CgA of the antibodies used in the two kits (r=0.61). The two assays had different accuracy also in classifying patients according to their clinical condition (91% vs 64% specificity and 79% vs 79% sensitivity for the ELISA and IRMA assay, respectively) and tumor histology (81% vs 85% sensitivity for the ELISA and IRMA assays, respectively, in carcinoids; 92% vs 67% sensitivity for the ELISA and IRMA assays, respectively, in pancreatic islet cell tumors). The different clinical accuracy of the two assays was confirmed by the ROC analysis (AUC=0.90 vs AUC=0.87 for the ELISA and IRMA assays, respectively). In conclusion, because of the poor standardization of the commercially available measurement tools the clinical accuracy of CgA measurement depends on the assay used. This makes it difficult to compare CgA values measured with different kits and affects the clinical accuracy of the different assays for CgA.
Effect of Opium Smoking on Concentrations of Carcinoembryonic Antigen and Tissue Polypeptide Antigen
Authors: Naghibalhossaini F. , Ay J. , Alavi J. , Oveisi S. , Chahardooli R.
Published: January 2018

Previous studies have related opium and its pyrolysates to the risk of developing certain cancers. The aim of this work was to evaluate the clinical usefulness of determining carcinoembryonic antigen (CEA) and tissue polypeptide antigen (TPA) levels in habitual opium smokers. Serum CEA concentrations were measured in 128 opium smokers and in 44 controls of cigarette only smokers and 47 normal non-smokers by an EIA-based assay. TPA levels were also determined in serum and urine of a subgroup in the study population. The results indicated that serum CEA concentrations are higher in opium smokers than in healthy tobacco smokers (p=0.004) and non-smokers (p=0.001). The amount of opium used correlated with the serum CEA level (r=0.276, p<0.0001). The mean urine and serum TPA levels of the opium-addicted population were also higher than that of the non-smoking control group, but the differences were not statistically significant. We conclude that opium smoking is associated with elevated serum CEA levels. Therefore, for management of opium users with neoplastic diseases, increased levels of serum CEA should be viewed with caution to avoid misdiagnosis.