bluuebunny/crossref_metadata_2025_split huggingface dataset:
Studies on glutathione metabolism in ventral prostate and chemically induced prostatic carcinoma in rats
Authors: Singhal Radhey L. , Vijayvargiya Rameshwar 
Published: February 2005

Glutathione content and the activity of glutathione reductase were examined in ventral prostate and chemically induced 11095 squamous-cell prostatic carcinoma in rats, Castration produced a significant reduction in the levels of reduced (GSH) and oxidized (GSSG) glutathione and glutathione reductase activity in the prostate. Replacement of testosterone (50 mg/kg) daily for 7 days to castrated animals elevated the reduced glutathione level and the activity of glutathione reductase almost to normal limits, Squamous-cell carcinoma was implanted in castrated and intact animals, Tumor growth in normal rats produced a decrease of almost 30% in the weight of the ventral prostate at 21 days post-implantation, although the glutathione levels remained unaffected. Much greater activity of glutathione reductase was detected in the tumor in comparison to the values noted for the normal tissue, The tumor also showed significantly higher values for the GSH/GSSG ratio, No apparent difference could be found in the rate of the growth of tumors whether implanted in normal or castrated animals, The levels of reduced and oxidized glutathione and glutathione reductase activity also seemed identical in tumors obtained from both groups of animals, Administration of testosterone (50 mg/kg) or β-estradiol (2 mg/kg) daily for 11 days to tumor-bearing castrated animals did not alter the levels of glutathione and glutathione reductase activity. A significantly higher level of blood reduced glutathione was found in tumor-bearing rats in comparison to that seen for the normal subjects.
Our results demonstrate that androgen depletion and replacement therapy influence the metabolism of glutathione in rat ventral prostate. Squamous-cell carcinoma of the prostate appears to differ from the normal tissue with respect to the observed androgen effects, There is dissimilarity in the metabolism of glutathione in the two tissues since greater activity of glutathione reductase and lower values of reduced glutathione were seen in the tumor as compared to those of the ventral prostate. Treatment with β-estradiol, an antiprostatic agent, does not seem to influence the growth or glutathione metabolism of squamous-cell carcinoma of the prostate. The observed changes in blood glutathione levels might prove to be useful as an index of rapid growth of the neoplastic tissue.
Co-operative nature of N-glycosylation of proteins at multiple sites: evidence from studies with tunicamycin
Authors: Cushley W. , Singer H. H. , Williamson A. R. 
Published: February 2005

The pattern of glycosylation of newly synthesized human and routine immunoglobulin μ-chains varies according to the degree of inhibition of N-glycosylation effected by using the antibiotic tunicamycin. Tunicamycin, at high concentrations, can apparently block N-glycosylation of μ-chains completely as judged by SDS-PAGE analysis of the biosynthetically labelled products. At lower concentrations of tunicamycin, fully giycosy]ated and totally non-glycosylated chains were the predominant molecular species. The paucity of the predicted partially glycosylated μ-chains leads us to suggest that the addition of oligosaccharides to the appropriate acceptor sites is a cooperative process.Long exposure of fluorographs reveals each of the predicted intermediately glycosylated forms of the μ-chain, and counting the number of bands on such fluorographs may prove useful in the preliminary determination of the number of N-linked oligosaccharides in a given glycoprotein.
Degradation artefacts during sample preparation for sodium dodecyl sulphate polyacrylamide gel electrophoresis
Authors: Cookson E. Jane , Beynon Robert J. 
Published: February 2005

Preparation of samples for sodium dodecyl sulphate polyacrylamide gel electrophoresis routinely involves heating the protein in solution containing detergent and reducing agent for at least two minutes. Here we show that this treatment causes fragmentation of the protein glycogen phosphorylase, whether purified or as a component of a skeletal muscle preparation. The fragments are detected as minor bands on western blots and represent the products of discrete breakage point in the peptide sequence. Protease inhibitors cannot suppress the fragmentation.
Such small amounts of immunoreactive fragments may be incorrectly identified on western blots as contaminants that were originally present in the antigen preparation. They may also be a source of ambiguity in studies that search for degradation intermediates during proteolysis.
British division of the international academy of pathology
Authors: Van Den Tweel J , Howat A J , Shepherd N A , Warren B F , Harris C 
Published: February 2005

Forthcoming meetings 5–8 July 2005 Joint Meeting with the Pathological Society of Great Britain and Ireland. Newcastle‐Upon‐Tyne, UK25–26 November 2005 Symposium on Intestinal Pathology. London, UK
Immunophenotypic alteration of the stromal component in minimal deviation adenocarcinoma (‘adenoma malignum’) and endocervical glandular hyperplasia: a study using oestrogen receptor and α‐smooth muscle actin double immunostaining
Authors: Mikami Y , Kiyokawa T , Moriya T , Sasano H 
Published: February 2005

Aims : To define the phenotypic alteration of the stromal component in association with destructive invasion which is a crucial feature in distinguishing minimal deviation adenocarcinoma (MDA) from benign endocervical glandular lesions.Methods and results : We studied endocervical glandular hyperplasias including non‐specific‐type (NEGH) (n = 3) and lobular‐type (LEGH) (n = 8), and minimal deviation adenocarcinoma (MDA) (n = 11), well‐differentiated endocervical adenocarcinoma of usual‐type (WDA) (n = 11), and adenocarcinoma in situ (AIS) (n = 6) of the cervix, by double immunostaining for oestrogen receptor (ER) and α‐smooth muscle actin (α‐SMA) using peroxidase‐ and alkaline phosphatase‐polymer methods, respectively. Glands in NEGH invariably showed nuclear staining for ER, with surrounding ER+/α‐SMA– stromal cells, whereas LEGH also harboured ER+/α‐SMA– spindle cells, but lacked nuclear staining for ER in constituent glands. In contrast, both WDA and MDA displayed accompanying stroma rich in α‐SMA+ spindle cells in close vicinity to the infiltrating neoplastic glands, with only occasional weakly ER+ stromal cells. WDA tended to contain more α‐SMA+ cells. The distribution of α‐SMA+ cells was periglandular (6/11), patchy (6/11), and/or diffuse (4/11) in WDA, whereas in MDA it was periglandular (11/11) and/or patchy (8/11). AIS was surrounded by ER+/α‐SMA− stromal cells. All cases of WDA, MDA, and AIS lacked nuclear staining for ER.Conclusions : Both MDA and WDA can be distinguished from LEGH and NEGH by identifying surrounding α‐SMA+ stromal cells and the absence or decreased number of ER+ cells, possibly as a result of the desmoplastic reaction with myofibroblasts replacing pre‐existing ER+ stromal cells. In particular, the periglandular distribution of these α‐SMA+ stromal cells can be a clue suggesting destructive stromal invasion in cases of MDA, although occasional glands may lack these cells.
Non‐invasive (intracapsular) carcinoma ex pleomorphic adenoma: recognition of focal carcinoma by HER‐2/neu and MIB1 immunohistochemistry
Authors: Di Palma S , Skálová A , Vanìèek T , Simpson R H W , Stárek I , Leivo I 
Published: February 2005

Aims : Non‐invasive carcinoma ex pleomorphic adenoma is defined as a carcinoma arising within the boundaries of a pleomorphic adenoma (PA), but which fails to display invasion beyond the capsule of host PA. Alternative names are intracapsular, in situ, or focal carcinoma. The true nature of non‐invasive carcinoma ex‐PA is still controversial; for example, it is not clear whether it represents early but genuine carcinomatous changes with the genetic make‐up of malignant cells, or simply cytological, possibly metaplastic or ‘bizarre’ changes in PA. Strong overexpression and amplification of HER‐2/neu protein has recently been demonstrated in invasive carcinoma ex‐PA. In addition, data from breast cancer studies suggest that amplification of HER‐2/neu and overexpression of its gene product is mainly involved in the initiation of breast oncogenesis. We sought to establish whether this method could help to demonstrate that what is described as non‐invasive carcinoma ex‐PA is really a genuine malignancy, albeit in an early phase.Methods and results : Eleven cases of non‐invasive carcinoma (in situ) ex‐PA were studied for HER‐2/neu status using immunohistochemistry and fluorescent in‐situ hybridization (FISH). Cells of focal non‐invasive carcinoma ex‐PA were strongly positive for HER‐2/neu protein, while the cells of the maternal PA were always negative. Two cases of low‐grade non‐invasive myoepithelial carcinoma ex‐PA were negative. In four cases out of a total of six tumours studied by FISH, we detected amplification of HER‐2/neu gene signals in tumour cells of focal, non‐invasive, carcinoma.Conclusions : The current data suggest that non‐invasive carcinoma ex PA is a genuine carcinoma within a PA. However, the presence of cyto‐nuclear atypia is not sufficient to make a definite diagnosis of malignant change, which requires a combination of morphology and immunohistochemistry.
Overexpression of Ets‐1 proto‐oncogene in latent and clinical prostatic carcinomas
Authors: Alipov G , Nakayama T , Ito M , Kawai K , Naito S , Nakashima M , Niino D , Sekine I 
Published: February 2005

Aims : The high incidence of clinically diagnosed prostatic cancer is exceeded by the frequency of tumours detected at autopsy. The Ets‐1 proto‐oncogene is expressed by a variety of malignant and normal tissues. Therefore, in this study, expression of Ets‐1 protein was investigated in ‘latent’ prostatic cancer detected at autopsy, compared with benign prostatic hyperplasia, normal prostatic tissues and clinical prostatic cancer.Methods and results : Using immunohistochemistry, we analysed Ets‐1 expression in 95 prostatic specimens including 19 cases of latent prostatic carcinoma (LPC) and 55 cases of clinical prostatic carcinoma (CPC), 11 cases of benign prostatic hyperplasia (BPH) and 10 cases of normal prostate (NP). Differences in the incidence of LPC and CPC suggest different courses for the biological progression of prostatic cancer. There was a significant difference in the degree of Ets‐1 expression in CPC and LPC (P < 0.05). Ets‐1 was not expressed in BPH and NP, but in malignant cases (57 of 74; 77.0%) commonly demonstrated immunoreactivity in the tumour cells. In our study the expression of Ets‐1 between benign and malignant, and well, moderately and poorly differentiated adenocarcinomas of prostatic cancer showed significant differences. The presence of Ets‐1 mRNA was confirmed by in‐situ hybridization in human prostatic tissues.Conclusion : Our results suggest that Ets‐1 might play an important role in carcinogenesis and/or the progression of human prostatic carcinomas.
PDGFRα‐ and c‐kit‐mutated gastrointestinal stromal tumours (GISTs) are characterized by distinctive histological and immunohistochemical features
Authors: Pauls K , Merkelbach‐Bruse S , Thal D , Büttner R , Wardelmann E 
Published: February 2005

Aims : To study the immunohistochemical and histological features of 158 gastrointestinal stromal tumours (GISTs), consisting of 137 tumours with mutations in c‐kit and platelet‐derived growth factor receptor‐alpha (PDGFRα) genes and 21 wt‐GISTs. Additionally, we evaluated the localization of PDGFRα in the normal intestine. PDGFRα gene mutations were recently described in a subset of GISTs and it has been hypothesized that PDGFRα‐mutated tumours represent a distinctive entity among GISTs.Results : PDGFRα was expressed in ganglion bodies of the myenteric plexus and in Schwann cells but not in interstitial cells of Cajal. In contrast to other GISTs, tumours with PDGFRα mutations had an epithelioid phenotype and multinuclear giant cells. Kit was down‐regulated in PDGFRα‐mutated GISTs and PDGFRα expression was decreased in c‐kit mutated tumours. Dot‐like staining of Kit and PDGFRα was associated very frequently with mutation within the respective gene.Conclusions : Features of PDGFRα‐mutated GISTs are multinuclear giant cells and dot‐like staining for PDGFRα. In contrast, c‐kit‐mutated GISTs display a spindle cell phenotype and Kit‐dots on immunohistochemistry. Our findings not only help to distinguish distinctive entities of GISTs using histological and immunhistochemical features, but also indicate that Kit and PDGFRα are differentially regulated in a subset of GISTs.
Expression of oestrogen receptor and loss of E‐cadherin are diagnostic for gastric metastasis of breast carcinoma
Authors: Van Velthuysen M‐L F , Taal B G , Van Der Hoeven J J M , Peterse J L 
Published: February 2005

Aims : To investigate whether immunohistochemical staining for oestrogen receptor (ER)α, progesterone receptor (PgR) and E‐cadherin might be useful to differentiate between metastatic breast carcinoma and primary gastric carcinoma.Methods : Gastric biopsies of 75 patients containing adenocarcinoma were stained for ERα, PgR and E‐cadherin. Included were: Group A, 28 patients with primary gastric cancer; Group B, 28 patients with an adenocarcinoma containing gastric biopsy and a clinical diagnosis of metastatic breast carcinoma; Group C, all consecutive patients with a positive gastric biopsy in 2001 (n = 19) without clinical history of breast carcinoma and not followed by gastric resection (control group).Results : All ERα+ or PgR+ carcinomas (n = 20) were of patients with a previous or concurrent history of breast carcinoma: 19 in group B, one in group C. In addition, absence of E‐cadherin staining was seen significantly more often in patients with metastatic breast carcinoma than in patients with primary gastric cancer (P < 0.001).Conclusion : Positive immunohistochemical staining for ERα or PgR of an adenocarcinoma in a gastric biopsy is diagnostic for metastatic breast carcinoma. Moreover, when carcinoma in a gastric biopsy is negative for E‐cadherin staining, metastatic breast carcinoma should be considered.
Superficial myofibroblastoma of the lower female genital tract: report of a series including tumours with a vulval location
Authors: Ganesan R , McCluggage W G , Hirschowitz L , Rollason T P 
Published: February 2005

Aims : To describe the clinical and pathological features of 12 further cases (in 11 patients) of superficial cervicovaginal myofibroblastomas (SCVM), rare tumours that hitherto have been described only in a single series of cases involving the cervix and vagina.Methods and results : The patients' ages ranged from 23 to 80 years. Ten tumours were located in the vagina and two in the vulva. Three patients had been taking tamoxifen. The tumours ranged in size from 2 to 45 mm and morphologically were well‐circumscribed lesions composed of bland ovoid to spindle‐shaped cells, often with wavy nuclei. These cells were arranged in a variety of architectural patterns and were set in a finely collagenous stroma. Five cases exhibited stromal oedema or myxoid change and in eight cases hyalinized areas with thick, dense collagen bundles were present. Immunohistochemically, there was positivity with vimentin (11 of 11 cases tested), CD34 (six of 12 cases), desmin (nine of 12 cases) and oestrogen receptor (nine of 11 cases). All cases tested were negative for smooth muscle actin, S100, h‐caldesmon, HMB45, and CD31. In this study we expand on the morphological spectrum of these rare lesions and reiterate their association with tamoxifen.Conculsions : Since these lesions may occur on the vulva, as well as the cervix and vagina, we propose the term ‘superficial myofibroblastoma of the lower female genital tract’.
Vascular endothelial growth factor (VEGF‐C1)‐dependent inflammatory response of podocytes in nephrotic syndrome glomerulopathies in children: an immunohistochemical approach
Authors: Ostalska‐Nowicka D , Zachwieja J , Nowicki M , Kaczmarek E , Siwinska A , Witt M 
Published: February 2005

Aims : To analyse expression and distribution of vascular endothelial growth factor (VEGF‐C1), podocalyxin and synaptopodin within renal tissue in nephrotic syndrome glomerulopathies in children.Methods and results : Renal biopsies performed at the time and in the manner recommended by the World Health Organization. The study group consisted of submicroscopic glomerulonephritis (n = 10), diffuse mesangial proliferation (n = 14) and focal segmental glomerulosclerosis (n = 5). The control tissue consisted of macroscopically normal appearing cortex taken from kidneys resected for localized neoplasms (n = 3). Material for immunohistochemistry was fixed in Bouin's solution and embedded in paraffin. Indirect immunohistochemistry using monoclonal anti‐human antibodies directed against VEGF‐C1, podocalyxin and synaptopodin was employed. The distribution of markers was quantified by computerized image analysis. In non‐sclerosed glomeruli (within podocyte cytoplasm), VEGF‐C1 was more expressed in podocytes of all groups (P < 0.0002), while the distribution of synaptopodin was less expressed in all groups (P < 0.0002). There was no statistical difference between all groups in the expression of podocalyxin.Conclusions : The increased permeability of the filtration barrier in steroid‐resistant glomerulopathies may be a consequence of subcellular changes in podocytes resulting from decreased expression of synaptopodin. Moreover, impaired permeability of endothelium could be secondary to increased expression of podocyte‐derived VEGF‐C1.
The expression and cellular localization of phosphorylated VEGFR2 in lymphoma and non‐neoplastic lymphadenopathy: an immunohistochemical study
Authors: Pillai G , Cook N , Turley H , Leek R D , Blasquez C , Pezzella F , Harris A L , Gatter K C 
Published: February 2005

Aims : To study the expression of phosphorylated vascular endothelial growth factor receptor 2 (VEGFR2), a membrane‐bound tyrosine kinase receptor to vascular endothelial growth factor, in lymphoma and non‐neoplastic lymphadenopathy.Methods and results : Archival cases (89 cases of lymphoma and 17 cases of non‐neoplastic lymphadenopathy) were studied immunohistochemically with three monoclonal antibodies to the different autophosphorylation sites in the cytoplasmic tail of the receptor. There was increased expression of this receptor in lymphoma and particularly in all cases of peripheral T‐cell lymphoma. In this category, there was nuclear re‐location of this receptor.Conclusions : This very interesting finding raises the possibility that VEGFR2 may be involved in the transcriptional regulation of this disease. Small molecule inhibitors to this receptor may therefore be a useful adjunct in the therapy of this disease.
On the Asymptotic Optimality of the Gradient Scheduling Algorithm for Multiuser Throughput Allocation
Authors: Stolyar Alexander L. 
Published: February 2005

We consider the model where N queues (users) are served in discrete time by a generalized switch. The switch state is random, and it determines the set of possible service rate choices (scheduling decisions) in each time slot. This model is primarily motivated by the problem of scheduling transmissions of N data users in a shared time-varying wireless environment, but also includes other applications such as input-queued cross-bar switches and parallel flexible server systems. The objective is to find a scheduling strategy maximizing a concave utility function H(u1,…,uN), where uns are long-term average service rates (data throughputs) of the users, assuming users always have data to be served. We prove asymptotic optimality of the gradient scheduling algorithm (which generalizes the well-known proportional fair algorithm) for our model, which, in particular, allows for simultaneous service of multiple users and for discrete sets of scheduling decisions. Analysis of the transient dynamics of user throughputs is the key part of this work.
Chiral stationary phase covalently bound with a chiral pseudo‐18‐crown‐6 ether for enantiomer separation of amino compounds using a normal mobile phase
Authors: Hirose Keiji , Yongzhu Jin , Nakamura Takashi , Nishioka Ryota , Ueshige Tetsuro , Tobe Yoshito 
Published: February 2005

AbstractIn order to apply the excellent chiral recognition ability of chiral pseudo‐18‐crown‐6 ethers that we developed to chiral separation, we prepared a chiral stationary phase (CSP) by immobilizing a chiral pseudo‐18‐crown‐6‐type host on 3‐aminopropyl silica gel. A chiral column was prepared by the slurry‐packing method in a stainless steel HPLC column. A liquid chromatography system using this CSP combined with the detection by mass spectrometry was used for enantiomer separation of amino compounds. A normal mobile phase can be used on this CSP as opposed to conventional dynamic coating‐type CSPs. Enantiomers of 18 common natural amino acids were efficiently separated. The chiral separation observed for amino acid methyl esters, amino alcohols, and lipophilic amines was fair using this HPLC system. In view of the correlation between the enantiomer selectivity observed in chromatography and the complexion in solution, the chiral recognition in host–guest interactions might contribute to this enantiomer separation. Chirality 17:142–148, 2005. © 2005 Wiley‐Liss, Inc.
Maintenance of gene expression patterns
Authors: Brock Hugh W. , Fisher Cynthia L. 
Published: February 2005

AbstractIn development, cells pass on established gene expression patterns to daughter cells over multiple rounds of cell division. The cellular memory of the gene expression state is termed maintenance, and the proteins required for this process are termed maintenance proteins. The best characterized are proteins of the Polycomb and trithorax Groups that are required for silencing and maintenance of activation of target loci, respectively. These proteins act through DNA elements termed maintenance elements. Here, we re‐examine the genetics and molecular biology of maintenance proteins. We discuss molecular models for the maintenance of activation and silencing, and the establishment of epigenetic marks, and suggest that maintenance proteins may play a role in propagating the mark through DNA synthesis. Developmental Dynamics 232:633–655, 2005. © 2005 Wiley‐Liss, Inc.