bluuebunny/crossref_metadata_2025_split huggingface dataset:
Identification of potato genes induced during colonization by Phytophthora infestans
Authors: Beyer Katinka , Binder Andres , Boller Thomas , Collinge Margaret 
Published: March 2003

SummarySuppression Subtractive Hybridization (SSH) was applied in a search for genes induced during the compatible interaction between Phytophthora infestans and potato. Using potato leaves that had been treated with benzo(1,2,3)thiadiazole‐7‐carbothioic acid S‐methylester (BTH) as the control tissue, a low redundancy library with a relatively low frequency of the classic plant Pathogenesis‐Related (PR) genes was generated. 288 of the clones were screened for induced sequences using Inverse Northern analysis (hybridizing the arrayed clones with radiolabelled cDNA populations). Of the 75 clones that were detectable by this method, 43 appeared to be induced. Eleven of these clones were then analysed by total RNA blot analysis, and elevation of transcript levels during P. infestans infection was confirmed for 10 of them. Some of the cDNAs analysed by RNA blot analysis have homology to genes already known to be induced during infection, e.g. to β‐1,3‐glucanase. Another group of cDNAs have homology to enzymes involved in detoxification: gamma‐glutamylcysteine synthetase, cytochrome P450, glutathione S‐transferase and an MRP‐type ABC transporter. Other infection induced cDNAs encode putative proteins that have not previously been reported to be induced by infection: e.g. the ER‐located chaperone BiP, and a homologue of Aspergillus nidulans SudD, which was isolated as a suppressor of a mutation in chromosome disjunction. The differential library therefore presents the opportunity to analyse the metabolic changes occurring during infection, and the disease process itself in more detail.
Reduced symptoms of Verticillium wilt in transgenic tomato expressing a bacterial ACC deaminase
Authors: Robison Mary M. , Shah Salehuzzaman , Tamot Bhaju , Pauls K. Peter , Moffatt Barbara A. , Glick Bernard R. 
Published: March 2003

SummaryEthylene evolved during compatible or susceptible disease interactions may hasten and/or worsen disease symptom development; if so, the prevention of disease‐response ethylene should reduce disease symptoms. We have examined the effects of reduced ethylene synthesis on Verticillium wilt (causal organism, Verticillium dahliae) of tomato by transforming tomato with ACC deaminase, which cleaves ACC, the immediate biosynthetic precursor of ethylene in plants. Three promoters were used to express ACC deaminase in the plant: (i) CaMV 35S (constitutive expression); (ii) rolD (limits expression specifically to the site of Verticillium infection, i.e. the roots); and (iii) prb‐1b (limits expression to certain environmental cues, e.g. disease infection). Significant reductions in the symptoms of Verticillium wilt were obtained for rolD‐ and prb‐1b‐, but not for 35S‐transformants. The pathogen was detected in stem sections of plants with reduced symptoms, suggesting that reduced ethylene synthesis results in increased disease tolerance. The effective control of formerly recalcitrant diseases such as Verticillium wilt may thus be obtained by preventing disease‐related ethylene production via the tissue‐specific expression of ACC deaminase.
The Potato virus Y MSNR NIb‐replicase is the elicitor of a veinal necrosis‐hypersensitive response in root knot nematode resistant tobacco
Authors: Fellers John P. , Tremblay Douglas , Handest Margaret F. , Lommel Steven A. 
Published: March 2003

SummaryA root knot nematode resistance gene in Nicotiana tabacum, Rk, providing resistance to the nematode parasite Meloidogyne incognita is tightly linked to, or is a pleiotropic gene with a veinal necrosis systemic hypersensitive response to infection by Potato virus Y (PVY) MsNr. The single PVY MsNr open reading frame was sequenced and found to have 89% protein identity to PVY N. Individual PVY MsNr polypeptides were deduced and the corresponding cDNA were cloned into a Potato virus X (PVX) based expression vector and used as templates for in vitro transcriptions. Infected plant sap, from N. benthamiana inoculated with infectious RNA, was used to inoculate both root knot nematode (RKN) resistant and susceptible tobacco lines. Lines were then evaluated for the induction of the hypersensitive response. The PVY MsNr NIb‐replicase protein was found to induce a hypersensitive response 10 days post inoculation in nematode resistant tobacco. None of the other PVX/PVY MsNr constructs induced a hypersensitive response. The NIb‐replicase of PVY N, which shares 93% identity to PVY MsNr, did not induce a hypersensitive response when expressed from the PVX vector. This confirmed that the PVY MsNr NIb‐replicase is the elicitor of PVY MsNr veinal necrosis on RKN plants and thus the first report of a Potyvirus replicase functioning as an avirulence factor.
Cowpea mosaic virus: effects on host cell processes
Authors: Pouwels Jeroen , Carette Jan E. , Van Lent Jan , Wellink Joan 
Published: March 2003

SUMMARYTaxonomy:  Cowpea mosaic virus (CPMV) is the type member of the Comoviridae and bears a strong resemblance to animal picornaviruses, both in gene organization and in the amino acid sequence of replication proteins. Little systematic work has been done to compare isolates of the virus from different parts of the world.Physical properties:  Purified preparations of virus contain three centrifugal components; empty protein shells without RNA (T) and two nucleoprotein components (M and B), containing 24% and 34% RNA, respectively. The icosahedral particles have with a diameter of 28 nm, consist of 60 copies of two coat proteins, and are heat stable.Hosts:  CPMV causes one of the most commonly reported virus diseases of cowpea (Vigna unguiculata), in which it produces chlorotic spots with diffuse borders in inoculated primary leaves. Trifoliate leaves develop a bright yellow or light green mosaic of increasing severity in younger leaves. The host range is rather limited, and few hosts are known outside the Leguminosae. The virus is transmitted by various beetles with biting mouthparts. Reported in Africa, the Philippines and Iran. Is apparently absent from North and South America.Useful website:  http://mmtsb.scripps.edu/viper/1cpmv.html (structure); http://image.fs.uidaho.edu/vide/descr254.htm (general information).
Characterization of oncogene‐silenced transgenic plants: implications for Agrobacterium biology and post‐transcriptional gene silencing
Authors: Escobar M. A. , Civerolo E. L. , Polito V. S. , Pinney K. A. , Dandekar A. M. 
Published: March 2003

SUMMARY Agrobacterium tumefaciens
tumorigenesis is initiated by the horizontal transfer of a suite of oncogenes that alter hormone synthesis and sensitivity in infected plant cells. Transgenic plants silenced for the
iaaM
and
ipt
oncogenes are highly recalcitrant to tumorigenesis, and present a unique resource to elucidate fundamental questions related to
Agrobacterium
biology and post‐transcriptional gene silencing (PTGS). The oncogene‐silenced transgenic tomato line 01/6 was used to characterize
A. tumefaciens
growth
in planta
and to screen for
iaaM
and
ipt
sequence variants. Even in the absence of macroscopic and microscopic indications of tumorigenesis,
A. tumefaciens
is capable of long‐term survival in the hypocotyl tissues of the 01/6 line.
A. tumefaciens
growth, however, is significantly reduced in the 01/6 line, with populations decreased by 96% relative to wild‐type at 52 days post‐inoculation. In addition, the 01/6 line displayed suppression of tumorigenesis against all 35 tested strains of
A. tumefaciens
. High target homology is an absolute requirement of PTGS, therefore this result suggests that regions of the
iaaM
and
ipt
oncogenes are very highly conserved across most
A. tumefaciens
strains. Finally, graft transmissibility of oncogene silencing was assessed by grafting various non‐silenced tomato genotypes on to the 01/6 line. Phenotypic and molecular evidence (tumorigenesis and absence of small interfering RNAs, respectively) suggest that oncogene silencing is not graft‐transmissible, at least to wild‐type and antisense
iaaM ‐over‐expressing genotypes.
E‐cadherin and calretinin: a useful combination of immunochemical markers for differentiation between mesothelioma and metastatic adenocarcinoma
Authors: Leers  , Aarts  , Theunissen  
Published: March 2003

Aims:To assess the diagnostic accuracy of combinations of antibodies in the differential diagnosis of metastatic carcinomas and mesotheliomas in pleural lesions.Methods and results:The specificity and sensitivity of the commercially available antibodies Ber‐EP4, MOC‐31, CEA, B72.3, CD15, E‐cadherin and calretinin were evaluated using an indirect immunoperoxidase staining technique. This technique was applied to formalin‐fixed, paraffin‐embedded tissue blocks of pleural lesions. Twenty‐one patients with metastatic carcinoma (MC) and 20 patients with malignant mesothelioma (MM) were included. The combination E‐cadherin/calretinin had the highest specificity (MC 100% and MM 91%) and sensitivity (MM 100% and MC 91%) considering both categories of tumours.Conclusions:The combination of E‐cadherin/calretinin appears to be a suitable panel for distinguishing metastatic carcinomas and mesotheliomas in pleural lesions. The additional value of other markers is limited.
Epithelioid haemangioendothelioma of the thyroid gland: a case report and review of literature
Authors: Siddiqui  , Evans  , Ro  , Ayala  
Published: March 2003

AimsThis is a hitherto unreported case of an epithelioid haemangioendothelioma of the thyroid gland.Methods and resultsThe patient was a 44‐year‐old woman who presented with a right thyroid mass. A right subtotal thyroidectomy was performed. Histologically the lesion had characteristic epithelioid and spindle cell proliferation in a background of chondromyxoid stroma. Cytoplasmic vacuolization in the epithelioid and spindle cells was present. No atypical mitotic activity or necrosis was noted. The tumour cells were positive for factor VIII‐related antigen, Ulex europeus and CD 31 and were negative for cytokeratin.ConclusionThe patient has been followed for 24 months and is free of recurrent and metastatic disease, which is supportive of a benign course in the thyroid gland.
Altered contractile proteins and neural innervation in idiopathic megarectum and megacolon
Authors: Gattuso J M , Smith V V , Kamm M A 
Published: March 2003

Aim: The aetiology of idiopathic megarectum and idiopathic megacolon is unknown. We postulated that biochemical or ultrastructural abnormalities may be pathophysiologically important, as has been observed in patients with chronic idiopathic intestinal pseudo‐obstruction.Methods and resultsResection specimens from five patients with idiopathic megarectum or megacolon were processed for paraffin wax‐embedded tissue histology (haematoxylin and eosin, Gomori trichrome and picrosirius stains, acid phosphatase activity and periodic acid–Schiff staining), and frozen tissue for histochemistry and electron microscopy. The antibodies used in the immunohistochemistry were to myosin light chain kinase, smooth muscle myosin, alpha and beta actins, filamin, tropomyosin, phosphorylated and de‐phosphorylated neurofilaments and N‐CAM. Variable hypertrophy of the muscularis mucosae and externa, no atrophy, and a variable nerve density decrease in longitudinal muscle and increase in the lamina propria was seen. In one patient beta actin and myosin light chain kinase immunoreactivity was reduced.ConclusionVariable changes in innervation, and an abnormal contractile protein immunoreactivity pattern in one patient, may be of pathogenic importance. These clinically homogeneous conditions are likely to be due to a range of underlying pathogenic abnormalities. A search for further specific biochemical abnormalities is justified.
Focal endometrial stromal hyperplasia
Authors: Stewart C J R , Michie B A , Kennedy J H 
Published: March 2003

AimsTo describe a patient in whom multiple endometrial biopsies revealed stromal proliferative lesions causing diagnostic difficulty.Methods and resultsA 39‐year‐old woman with a history of menorrhagia and dysmenorrhoea underwent two endometrial biopsies and hysterectomy. In each case histopathology revealed apparently multifocal benign stromal proliferative lesions with no evidence of invasive growth pattern. The lesions were characterized by increased cellularity, nuclear enlargement and spindle cell morphology but no mitotic activity or nuclear pleomorphism were seen. The possibility of low grade stromal neoplasm was considered in the biopsy specimens. The hysterectomy revealed no evidence of malignancy but foci of ovarian endometriosis and cervical stromal endometriosis were present.ConclusionWe suggest that the lesions represent focal endometrial stromal hyperplasia, a potential mimic of stromal nodule or stromal sarcoma in biopsy samples.
Reduced expression of retinoic acid receptor beta protein (RARβ) in human papillary thyroid carcinoma: immunohistochemical and Western blot study
Authors: Rochaix Ph , Monteil‐Onteniente S , Rochette‐Egly C , Caratero C , Voigt J J , Jozan S 
Published: March 2003

AimsTo investigate the role of retinoic acid receptor beta (RARβ) in thyroid carcinogenesis, we have investigated its expression in human thyroid samples by combined immunohistochemistry and Western blotting.Methods and resultsFifty‐eight paraffin‐embedded thyroid samples (40 normal or benign tissues, 16 papillary and two follicular carcinomas) were analysed by immunohistochemistry using a specific monoclonal antibody. Western blotting was also carried out on 11 selected samples (seven normal or benign tissues, three papillary carcinomas and one follicular carcinoma) and two human ovarian carcinomas as controls. RARβ immunostaining was nuclear and limited to the normal epithelial thyroid tissue. A dramatic decrease in RARβ immunostaining was observed in all the papillary carcinomas and in one follicular carcinoma. The other follicular carcinoma exhibited strong RARβ immunostaining. By immunoblotting, a 51 kDa signal corresponding to the RARβ was observed in nuclear extracts from normal thyroids and for one follicular carcinoma. However, this signal was lacking in the papillary carcinomas. These results were in complete agreement with the observations obtained by immunohistochemistry on the same samples.ConclusionWe present here the first demonstration of RARβ protein in normal human thyroid follicular cells. In addition, we found that its expression is decreased in papillary thyroid carcinoma.
Synovial sarcoma of the pleura and its differentiation from other primary pleural tumours: a clinicopathological and immunohistochemical review of three cases
Authors: Nicholson  , Goldstraw  , Fisher  
Published: March 2003

Aims: Synovial sarcomas are rare tumours occasionally arising in the pleural cavity, a site where their histological characteristics may be mistaken for those of malignant mesothelioma. We examined three cases of primary pleural synovial sarcoma in order to look for clinicopathological features that may help in distinguishing them from both mesotheliomas and other sarcomas that may arise in the pleura.Methods and resultsAll three patients were male, aged 42, 28 and 42, respectively, and had no known exposure to asbestos. One biphasic tumour contained neutral mucin in focal epithelial elements that also stained positively for BerEP4 and AUA1. All three tumours showed focal positivity for either keratin or EMA in the sarcomatous elements, and they also stained positively for bcl‐2 protein and MIC2 gene product (CD99).ConclusionsOur results emphasize the importance of being aware of synovial sarcoma as a possible primary pleural malignancy, especially in a young patient with a localized mass. In addition, the presence of bcl‐2 protein perhaps represents a useful marker in distinguishing synovial sarcoma, especially monophasic variants, from mesothelioma within a panel of antibodies.
Primary juxtaarticular soft tissue lymphoma arising in the vicinity of inflamed joints in patients with rheumatoid arthritis
Authors: Goodlad  , Hollowood  , Smith  , Chan  , Fletcher  
Published: March 2003

AimsPrimary soft tissue lymphoma is uncommon and little is known regarding its aetiology and pathogenesis. In a review of 37 soft tissue lymphomas we uncovered three cases associated with rheumatoid arthritis which we report herein.Methods and resultsThe clinical records and pathology of the cases are described together with the results of in situ hybridization studies with oligonucleotide probes to Epstein–Barr virus (EBV) encoded RNA (EBER). All three patients were females with a long‐standing history of rheumatoid arthritis ranging from 9 to 17 years. Each presented with a soft tissue mass in the vicinity of a joint affected by rheumatoid disease. All had received prior treatment with nonsteroidal anti‐inflammatory drugs and one also received gold, penicillamine and intra‐articular steroids to affected joints. None had received methotrexate. Histologically, the juxtaarticular soft tissue masses were all B‐cell lymphomas. None were associated with EBV as determined by in situ hybridization.ConclusionsThese cases document an association between rheumatoid arthritis and soft tissue lymphoma of B‐cell type, arising in the vicinity of an affected joint. Chronic local immune stimulation may have played a significant role in the genesis of these lymphomas, unlike the frequently reversible and EBV‐positive lymphomas that occur in rheumatoid patients on immunosuppressive therapy.
p53 expression in phyllodes tumours is associated with histological features of malignancy but does not predict outcome
Authors: Feakins R M , Mulcahy H E , Nickols C D , Wells C A 
Published: March 2003

AimsTo study p53 protein expression in phyllodes tumours of the breast, with particular attention to its prevalence and to its relationship with histological features and clinical outcome.Methods and resultsStromal and epithelial p53 immunohistochemical expression was studied in 57 phyllodes tumours (27 benign, 17 borderline, 13 malignant) using an avidin–biotin peroxidase method. High levels of expression (> 30% of stromal nuclei) were found in eight phyllodes tumours (14%). p53 expression was associated with tumour grade (P = 0.001), prominent stromal overgrowth (P = 0.0003), prominent stromal nuclear pleomorphism (P = 0.006), high stromal mitotic count (P = 0.05), and an infiltrative tumour margin (P = 0.05). Six patients were lost to follow‐up after surgery. Mean follow‐up time of the remaining 51 patients was 7.3 years (median 4.3, range 0.5–25) or until death. Sixteen patients (31%) experienced tumour recurrence. Recurrence was more likely if there was an infiltrative tumour margin (P = 0.006) or prominent stromal overgrowth (P = 0.04) but not p53 expression (P = 0.55). A minority of recurrences expressed p53 more extensively than their primary counterparts. There were five tumour‐related deaths (10% of patients). Death was associated with high grade (P = 0.0002), prominent stromal overgrowth (P = 0.0001), an infiltrative margin (P = 0.0002), prominent nuclear pleomorphism (P = 0.005), a high mitotic count (P = 0.01) and tumour size (P = 0.03). Again, p53 expression was not associated with tumour‐related survival (P = 0.13).Conclusionsp53 abnormalities occur in a minority of borderline and malignant phyllodes tumours. p53 expression is associated with known negative prognostic factors, but does not appear to be a useful determinant of tumour recurrence or long‐term survival.
Adenoid cystic carcinoma of the breast: a tumour commonly devoid of oestrogen receptors and related proteins
Authors: Trendell‐Smith  , Peston  , Shousha  
Published: March 2003

AimAdenoid cystic carcinoma (ACC) of the breast is an uncommon well‐differentiated tumour with good prognosis, and sometimes difficult to distinguish from in‐situ and invasive cribriform carcinoma (ICC) which are relatively more common. Recently, we encountered a case of ACC that proved to be totally oestrogen receptor (ER) negative by immunohistochemistry. We investigated the possibility that this may be a consistent feature that can help in differentiating ACC from ICC which are usually ER positive.Methods and resultsThe immunoperoxidase technique was used to study the expression of ER and other related proteins in six cases of ACC and two cases of ICC. All ACC cases were negative for oestrogen (ER) and progesterone (PgR) receptors whereas the two ICC were strongly positive for ER and showed a variable degree of PgR positivity. In addition, ACC cases were pS2 negative and showed minimal expression of prolactin receptors (PrlR), while the two ICC showed widespread and strong staining for pS2 and PrlR. The percentages of cells staining positively for Ki67 and p27 were generally lower in ACC than in ICC. Both tumour types were c‐erbB‐2 negative, but p53 was weakly to moderately positive.ConclusionsThe findings suggest that a negative immunoperoxidase staining for ER would confirm the diagnosis of ACC in contrast to the positive staining which is always seen in ICC. The findings also raise the issue of the presence of a specific class of ER negative breast carcinomas which are negative not because of poor differentiation, but because of their derivation from, or differentiation along, an ER negative cell lineage.
Intravascular tumour in intra‐oral pleomorphic adenomas: a diagnostic and therapeutic dilemma
Authors: Coleman  , Altini  
Published: March 2003

AimsIntravascular tumour has been described very rarely in pleomorphic adenomas. The aim of this study was to establish the frequency of intravascular tumour in pleomorphic adenomas arising in minor salivary glands and to determine the biological significance of this phenomenon.Methods and resultsRepresentative sections of 67 widely excised pleomorphic adenomas were examined for the presence of intravascular tumour. Sixty‐two cases were derived from the palate while the remaining five were from the cheeks and lips. In instances where intravascular tumour was identified, multiple serial sections were assessed and immunohistochemical stains were performed. None of these cases showed cytological evidence of malignancy. Solid cords of intravascular tumour were present in six palatal tumours (8.9%) and consisted of plasmacytoid myoepithelial cells permeating muscular walled blood vessels and capillaries both within the tumour and capsule. Immunoperoxidase staining confirmed that the intravascular cells were phenotypically identical to those of the tumour being S100‐ and smooth muscle actin (SMA) positive. There is some evidence that this phenomenon represents true vascular invasion although artefactual spillage cannot be excluded.ConclusionsAlthough the biological significance of intravascular tumour in pleomorphic adenomas of minor salivary glands remains unknown, the occurrence of metastatic disease has not been demonstrated nor have aggressive behaviour or recurrences.