Evolving knowledge for the solution of clustering problems in cellular manufacturing

Hierarchical clustering has been widely used for the solution of problems in the area of cellular manufacturing. Hierarchical clustering procedures utilize coefficients that quantify the level of similarity between pairs of machines or parts in the plant. An evolutionary methodology is proposed for the construction of new similarity coefficients that can be used by standard hierarchical clustering methodologies for the solution of cell-formation problems. A typical application is presented for the simplest case of the cell-formation problem. However, alternative similarity coefficients can be evolved for advanced formulations of the problem by suitably modifying the set of fitness cases that constitute the environment of the evolutionary process.     

Favorable outcome of ovarian germ cell malignancies treated with cisplatin or carboplatin-based chemotherapy: a Hellenic Cooperative Oncology Group study

The effect of pretreatment of human polymorphonuclear leukocites (PMNs), for 30 min with fluconazole (0.1, 1, 5 and 50 microgram/ml) and itraconazole (0.05, 0.5 and 5 microgram/ml) on phagocytosis and generation of free radicals (superoxide anion and hydrogen peroxide) was studied in vitro. Phorbol miristate acetate (200 nM) was used as a stimulant. The mean amount of superoxide anion generated by 2.5 x 10(5) PMNs per hour was 4.39 +/- 1.13 nmol for fluconazole-treated PMNs and 4.56 +/- 1.2 nmol for itraconazole, and that of hydrogen peroxide was 11.19 +/- 2.18 and 11.28 +/- 3.61 nmol, respectively. The phagocytosis percentages were 83.8% for the control group and 88. 7% in antifungal agent- treated PMNs; the phagocytosis index was 3.0 yeasts per PMN for both groups. The differences between the control and treated PMNs were not statistically significant at any of the tested concentrations.     

Management of blood pressure instability in severe tetanus: the use of clonidine

OBJECTIVE: To evaluate the effectiveness of clonidine in the management of unstable blood pressure in severe tetanus. DESIGN: Patients with severe tetanus and blood pressure instability were treated with clonidine and the results were compared with those of other patients with severe tetanus who were not treated with clonidine. SETTING: Intensive care unit of the Chest Hospital of Athens. PATIENTS: We studied 27 patients with severe tetanus and autonomic dysfunction. INTERVENTIONS: Patients were managed according to a protocol. MEASUREMENTS AND RESULTS: Clonidine was administered until blood pressure stability was the fully restored and the dose was then gradually reduced. Five patients from the nonclonidine group and 2 from the clonidine group died. CONCLUSIONS: These results suggest that clonidine is effective in the treatment of blood pressure instability in severe tetanus.     

Magnetic resonance imaging in the staging of solitary plasmacytoma of bone

PURPOSE: To assess prospectively the role of magnetic resonance (MR) imaging in the staging of patients with a solitary bone plasmacytoma (SBP). PATIENTS AND METHODS: Twelve consecutive patients with an apparent SBP underwent MR imaging of both the primary tumor and the thoracic and lumbosacral spine to seek additional foci of marrow involvement that might have been undetected by standard skeletal survey. All patients received megavoltage irradiation (total dose, 40 Gy) to the primary lesion. RESULTS: MR imaging of the thoracic and lumbosacral spine showed additional foci of marrow replacement in four of 12 patients, with signal characteristics identical to those of the primary tumor. In all four patients, the abnormal protein persisted at greater than 50% of the pretreatment value following radiation treatment. In contrast, the myeloma protein disappeared or was reduced by greater than 50% in five of the six patients with secretory disease and without additional marrow abnormalities. One of four patients progressed to multiple myeloma 10 months after diagnosis with new lesions on conventional radiographs in the same areas as detected previously by MR imaging. CONCLUSION: Four of 12 patients considered to have a SBP by standard criteria may have been understaged, because MR imaging showed additional marrow abnormalities consistent with myeloma. MR imaging of the spine may contribute to the initial staging of SBP, especially since some patients may be cured with radiotherapy.     

Angiogenesis-Related Pathways in the Pathogenesis of Ovarian Cancer

Ovarian Cancer represents the most fatal type of gynecological malignancies. A number of processes are involved in the pathogenesis of ovarian cancer, especially within the tumor microenvironment. Angiogenesis represents a hallmark phenomenon in cancer, and it is responsible for tumor spread and metastasis in ovarian cancer, among other tumor types, as it leads to new blood vessel formation. In recent years angiogenesis has been given considerable attention in order to identify targets for developing effective anti-tumor therapies. Growth factors have been identified to play key roles in driving angiogenesis and, thus, the formation of new blood vessels that assist in “feeding” cancer. Such molecules include the vascular endothelial growth factor (VEGF), the platelet derived growth factor (PDGF), the fibroblast growth factor (FGF), and the angiopoietin/Tie2 receptor complex. These proteins are key players in complex molecular pathways within the tumor cell and they have been in the spotlight of the development of anti-angiogenic molecules that may act as stand-alone therapeutics, or in concert with standard treatment regimes such as chemotherapy. The pathways involved in angiogenesis and molecules that have been developed in order to combat angiogenesis are described in this paper.     

Cure kinetics,glass transition temperature development,and dielectric spectroscopy of a low temperature cure epoxy/amine system

This article reports a study of the chemical cure kinetics and the development of glass transition temperature of a low temperature (40°C) curing epoxy system (MY 750/HY 5922). Differential scanning calorimetry, temperature modulated differential scanning calorimetry, and dielectric spectroscopy were utilized to characterize the curing reaction and the development of the cross‐linking network. A phenomenological model based on a double autocatalytic chemical kinetics expression was developed to simulate the cure kinetics behavior of the system, while the dependence of the glass transition temperature on the degree of cure was found to be described adequately by the Di Benedetto equation. The resulting cure kinetics showed good agreement with the experimental data under both dynamic and isothermal heating conditions with an average error in reaction rate of less than 2 × 10^?3 min^?1. A comparison of the dielectric response of the resin with cure kinetics showed a close correspondence between the imaginary impedance maximum and the calorimetric progress of reaction. Thus, it is demonstrated that cure kinetics modeling and monitoring procedures developed for aerospace grade epoxies are fully applicable to the study of low temperature curing epoxy resins. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

The prevalence of bcl-2, p53, and Ki-67 immunoreactivity in transitional cell bladder carcinomas and their clinicopathologic correlates

The aim of this study was to investigate the expression of bcl-2, p53 oncoproteins, and Ki-67 antigen in a series of transitional cell bladder carcinomas and its relation to the traditional prognostic indicators and patient's survival. One hundred six cases with transitional cell carcinoma (TCC) were examined for detection of bcl-2, p53 proteins, and Ki-67 antigen (MIB1 antibody). Bcl-2 immunohistochemical positivity was observed in 52% of TCCs and in 57% of low-grade and 44% of high-grade TCCs. Bcl-2 was also detected in normal urothelium and dysplastic lesions with basal cell expression, and negative staining was observed in carcinomas in situ. Tumor stage showed a significant inverse correlation with overall bcl-2 positivity. The loss of bcl-2 protein expression in higher-stage TCCs was statistically significant (Pt = .01). p53 protein was overexpressed in 50% of TCCs and more frequently in invasive and in carcinomas in situ than in superficial TCCs (Pt = .03). In contrast, detection of p53 was not observed in normal and dysplastic urothelium. p53 positivity was related to the degree of differentiation and to the stage of the disease (Pf = .01 and Pt = .03, respectively). Concerning Ki-67 antigen, its expression was found in 57.5% of TCCs. There was a strong overall correlation of Ki-67 with tumor stage (Pt = .002) and grade (Pf = .002). Univariate statistical analysis showed that the expression of p53 and Ki-67 was significantly correlated to poor prognosis (P = .02, P = .02, respectively). On multivariate analysis, none of these markers but only stage and grade were significantly correlated to prognosis (P = .02, P = .02, respectively). These findings suggest that overexpression of bcl-2 protein may be an early event in tumorigenesis. Tumors with loss of bcl-2 positivity and overexpression of p53 and Ki-67 had an unfavorable prognosis; however, in multivariate analysis, they had no independent prognostic value.     

Comparing neural networks in the discrimination of benign from malignant lower urinary tract lesions

BACKGROUND: Angiocentric cutaneous T-cell lymphomas of childhood (ACTCLC) are an unusual type of T-cell lymphomas that present with a vesiculopapular eruption mimicking hydroa vacciniforme. Most patients have been children from Asia and Latin America. OBJECTIVE: The purpose of this study was to describe four cases of ACTCLC; to discuss its clinical, histopathologic, and immunohistochemical features; to consider its possible relationship to the Epstein-Barr virus (EBV); and to clarify its classification within the spectrum of angiocentric lymphomas. METHODS: The clinical, histopathologic, and immunohistochemical features of four cases of ACTCLC were identified and analyzed. In addition in situ hybridization for EBV was performed in all cases. RESULTS: The clinical features were similar to previous cases reported under different names, such as hydroa-like lymphomas, edematous, scarring vasculitic panniculitis. Histologically, all showed angiocentric infiltrates composed mainly of T cells. In all cases there were variable numbers of CD30+ cells. The EBV was present in three of the cases. CONCLUSION: ACTCLC is a distinct type of T-cell lymphoma. It affects mainly children, and the EBV appears to play a role in the pathogenesis of this disease.     

Role of adjuvant chemotherapy in the treatment of invasive carcinoma of the urinary bladder

PURPOSE: The standard treatment for patients with muscle-invasive carcinoma of the urinary bladder is radical cystectomy. While radical cystectomy cures many patients with this tumor, almost 50% of them will develop metastatic disease. Adjuvant chemotherapy has been proposed for these patients in an attempt to reduce the probability of relapse and to improve survival. To assess whether adjuvant chemotherapy does benefit patients with muscle-invasive bladder cancer, we reviewed all phase II and III studies published in the English literature over the last 20 years. METHODS: A review of all published reports was facilitated by the use of Medline computer search and by manual search of the Index Medicus. RESULTS: Several comparative, nonrandomized studies have indicated that adjuvant chemotherapy may prolong disease-free survival. Four randomized studies have been conducted and all had a suboptimal patient accrual. Three studies used a cisplatin-containing combination chemotherapy and included primarily patients with non-organ-confined transitional-cell carcinoma (TCC) of the bladder. All three studies indicated that adjuvant chemotherapy improved disease-free survival and two of them also showed improvement in event-free survival and overall survival, respectively. CONCLUSION: Published series have been unable to establish an undisputed benefit of adjuvant chemotherapy over radical cystectomy alone for muscle-invasive bladder cancer. The interpretation of the available data is compromised by several methodologic and statistical problems. Thus, adjuvant chemotherapy cannot be considered as a standard treatment for all patients with muscle-invasive carcinoma of the bladder. Well-designed prospective randomized studies are needed to clarify the role of adjuvant chemotherapy in this disease. However, outside a protocol setting, there is some evidence that patients with extravesical disease or with lymph node involvement may benefit from adjuvant treatment with cisplatin-based combination chemotherapy. No data support such an approach for patients with muscle-invasive but organ-confined bladder cancer.     

Optimal total exchange in Cayley graphs

Consider an interconnection network and the following situation: Every node needs to send a different message to every other node. This is the total exchange or all-to-all personalized communication problem, one of a number of information dissemination problems known as collective communications. Under the assumption that a node can send and receive only one message at each step (single-port model), it is seen that the minimum time required to solve the problem is governed by the status (or total distance) of the nodes in the network. We present a time-optimal solution for any Cayley network. Rings, hypercubes, cube-connected cycles, and butterflies are some well-known Cayley networks which can take advantage of our method. The solution is based on a class of algorithms which we call node-invariant algorithms and which behave uniformly across the network