bluuebunny/crossref_metadata_2025_split huggingface dataset:
Brome mosaic virus, good for an RNA virologist’s basic needs
Authors: Kao C. Cheng , Sivakumaran K. 
Published: March 2003

Abstract Taxonomic relationship: Type member of the Bromovirus genus, family Bromoviridae. A member of the alphavirus‐like supergroup of positive‐sense single‐stranded RNA viruses. Physical properties: Virions are nonenveloped icosahedrals made up of 180 coat protein subunits (
Fig. 1). The particles are 26 nm in diameter and contain 22% nucleic acid and 78% protein. The BMV genome is composed of three positive‐sense, capped RNAs: RNA1 (3.2 kb), RNA2 (2.9 kb), RNA3 (2.1 kb) (
Fig. 2).Electron micrograph of brome mosaic virus. The average diameter of each particle is 26 nm.imageSchematic of BMV RNAs, and the initiation sites for viral RNA synthesis. (A) The RNAs are capped with a 7‐methyl‐guanylate at the 5′ end and possess a tRNA‐like structure at the 3′ end. The initiation sites of minus‐strand RNA synthesis from the penultimate cytidylate are indicated with an arrow. The protein coding sequences are indicated in boxes. The position of the domain in protein 1a that is highly conserved in capping‐associated proteins is denoted with verticle stripes. The region denoted with horizontal stripes contains helicase‐like motifs. The grey region in 2a contains the central RdRp‐like sequences. (B) Minus‐strand RNA3 is used to promote synthesis of genomic RNA3 and subgenomic RNA4 (orf, open reading frame).image Viral proteins: RNA1 encodes protein 1a, containing capping and putative RNA helicase activities. RNA2 encodes protein 2a, a putative RNA‐dependent RNA polymerase. RNA3 codes for two proteins: 3a, which is required for cell‐to‐cell movement, and the capsid protein. The capsid is translated from a subgenomic RNA, RNA4 (1.2 kb). Hosts: Monocots in the Poacea family, including Bromus inermis, Zea mays and Hordeum vulgare, in which BMV causes brown streaks. BMV can also infect the dicots Nicotiana benthamiana and several Chenopodium species. In N. benthamiana, the infection is asymptomatic while infection of Chenopodium can cause either necrotic or chlorotic lesions. Useful website:
http://www4.ncbi.nlm.nih.gov/ICTVdb/ICTVdB/10030001.htm
In situ PCR detection of phytoplasma DNA in embryos from coconut palms with lethal yellowing disease
Authors: Cordova Ivan , Jones Phil , Harrison Nigel A. , Oropeza Carlos 
Published: March 2003

SUMMARYDNA of the lethal yellowing (LY) phytoplasma was detected in 13 of 72 embryos from fruits of four diseased Atlantic tall coconut palms by polymerase chain reaction (PCR) assays employing phytoplasma universal rRNA primer pair P1/P7, nested LY group‐specific rRNA primer pair 503f/LY16Sr or LY phytoplasma‐specific nonribosomal primer pair LYF1/R1. Phytoplasma distribution in sectioned tissues from six PCR positive embryos was determined by in situ PCR and digoxigenin‐11‐deoxy‐UTP (Dig) labelling of amplification products. Dig‐labeled DNA products detected by colourimetric assay were clearly evident on sections from the same three embryos investigated in detail by in situ PCRs employing primer pairs P1/P7 or LYF1/R1. Deposition of blue–green stain on sections as a result of each assay was restricted to areas of the embryos corresponding to the plumule and cells ensheathing it. By comparison, similarly treated embryo sections derived from fruits of a symptomless Atlantic tall coconut palm were consistently devoid of any stain. Presence of phytoplasma DNA in embryo tissues suggests the possible potential for seed transmission which remains to be demonstrated.
Characterization of homologues of the apple proliferation immunodominant membrane protein gene from three related phytoplasmas
Authors: Morton Anne , Davies David L. , Blomquist Cheryl L. , Barbara Derek J. 
Published: March 2003

SUMMARYHomologues of the immunodominant membrane protein gene from apple proliferation (AP) phytoplasma have been cloned and sequenced for three further members of the AP subclade, namely European stone fruit yellows, peach yellow leaf roll and a European isolate of pear decline (PD). The putative translation products of all three were similar in size to that of AP and all had a transmembrane region towards the N‐terminus and a large C‐terminal hydrophilic domain, probably held on the outside of the cell membrane in vivo. Sequence similarities for the putative proteins were compared with interrelationships of the phytoplasmas as measured by rRNA gene sequence similarity. The proteins from AP and PD were more similar (57% identical in the major hydrophilic domain) than those for any other pair (31–34%), but these two phytoplasmas were not more closely related by rRNA gene sequences than other pairs. The possibility that the relative similarities of these proteins is related to the host is discussed. It is suggested that the similarity of the AP and PD proteins may reflect the fact that these two proteins have narrow plant host ranges in two closely related genera in the tribe Maloideae (family Rosaceae), whilst the other two have broader host ranges, mainly in the tribe Prunoideae.
Autopsy findings in 27 children with haemophagocytic lymphohistiocytosis
Authors: Öst  , Nilsson‐Ardnor  , Henter  
Published: March 2003

Aims:Primary haemophagocytic lymphohistiocytosis (HLH) is a fatal childhood disorder. The diagnosis is difficult to establish, clinically as well as histopathologically, and it is markedly underdiagnosed. Because of these difficulties, we wanted to elucidate the histopathological findings in population‐based patient material.Methods and results:The post‐mortem findings in 27 children with primary HLH diagnosed in Sweden between 1971 and 1986 was reviewed. Twelve of these patients had an affected sibling and three additional children had parental consanguinity. Some of the children showed generalized disease, whereas in others only one or a few organs were affected. The major histological alteration was an accumulation of primarily lymphocytes, but also of histiocytes, some of which exhibited evidence of haemophagocytosis. The haemophagocytic activity may be difficult to detect if there are pronounced post‐mortem changes, particularly in the spleen, and it is therefore preferable to perform the autopsy as soon as possible after death in order to minimize autolysis. Haemophagocytosis was most commonly observed in the spleen (17/24), the lymph nodes (17/23) and the bone marrow (9/23), indicating that a negative bone marrow examination does not rule out this diagnosis. Three additional patients had discrete signs of haemophagocytosis in the bone marrow. In the spleen, the lymph nodes and the bone marrow, lymphocytic depletion, pronounced in some cases, could be observed, even without prior treatment with steroids or cytostatics. In the liver, most of the patients demonstrated an infiltration of lymphocytes into the portal tracts similar to that seen in chronic persistent hepatitis (22/27), a finding which is uncommon in infancy and therefore suggestive of the diagnosis HLH. Other organs involved included the thymus, lungs, intestine, pancreas, kidney, heart and striated muscle.Conclusions:The diagnosis of HLH must be based on clinical, histological and additional laboratory findings. A negative bone marrow examination is common. Previous treatment with steroids and/or cytostatic drugs may attenuate or even eliminate the typical histological findings. Liver findings similar to those in chronic persistent hepatitis are common.
CD44 variant expression in inflammatory colonic mucosa is not disease specific but associated with increased crypt cell proliferation
Authors: Fromont Hankard  , Cezard  , Aigrain  , Navarro  , Peuchmaur  
Published: March 2003

Aims:A recent study reported increased epithelial expression of CD44 variants in ulcerative colitis (UC) compared with Crohn's disease (CD). However, the use of CD44 expression for diagnostic purposes in inflammatory bowel disease has been controversial, and the meaning of the appearance of CD44 variants in epithelial colonic cells remains unknown. We investigated the relationship between CD44 isoform expression and crypt cell proliferation in paediatric colitis.Methods and results:The expression of CD44v3, CD44v6, and MIB1 (proliferation marker) was studied by immunohistochemistry on surgical colonic samples of UC (n = 13), CD (n = 10), colostomy resections with non‐specific mucosal inflammation (NSMI) (n = 3), and normal controls (n = 5). The proliferation index (% of MIB1 positive cells) was assessed in both v6 positive and v6 negative crypts. Epithelial expression of CD44v3 and v6, negative in normal controls, was variable and focal in colitis. No preferential expression of CD44 variants was found in UC. The proliferation index was dramatically increased in v6 positive crypts compared with v6 negative crypts in UC, CD and NSMI.Conclusions:These data suggest that CD44 variant staining is not a useful marker for distinguishing paediatric UC from CD, and that CD44v6 expression in the inflamed colonic mucosa is not disease specific but is related to crypt cell proliferation.
Clear cell carcinoma of the pancreas: an adenocarcinoma with ductal phenotype
Authors: Lüttges  , Vogel  , Menke  , Henne‐Bruns  , Kremer  , Klöppel  
Published: March 2003

AimsPrimary clear cell carcinoma of the pancreas resembling metastatic renal carcinoma has only rarely been described. To date it has been poorly characterized as a distinct tumour entity.Methods and resultsWe report a case of clear cell carcinoma in a 53‐year‐old man involving the head of the pancreas and which had a small intraductal papillary component. The clear cell portion comprised about 90% of the tumour mass. It showed predominantly a solid growth pattern with a few scattered tubular structures. Immunocytochemically the tumour cells stained positively for cytokeratins 7, 8, 18 and 19, whereas the reaction for vimentin and neuroendocrine markers was negative. K‐ras analysis revealed a point mutation at codon 12 with mutation of GGT to GAT.ConclusionThe intraductal tumour component of this clear cell carcinoma as well as the cytokeratin pattern and the K‐ras mutation suggest that this rare type of pancreatic cancer has a ductal phenotype.
Histological demarcation of lateral borders: an unsupportable criterion for distinguishing malignant melanoma from Spitz naevus and compound naevus
Authors: Okun M R 
Published: March 2003

AimsThe objective of this study was to determine the validity of sharpness of lateral margins (an important component of the pattern analysis method) as a criterion for the histological distinction of naevi from malignant melanoma.Methods and resultsThe sharpness of lateral borders in a series of histologically unequivocal malignant melanomas, Spitz naevi and compound naevi, chosen at random from dermatopathology slide archives, was determined. The incidence of poor demarcation of lateral borders in malignant melanomas was about equal to that of Spitz naevi and was significantly less than in compound naevi. The sharpness of lateral borders frequently varies with level of sectioning.ConclusionsThe proposal that malignant melanomas have a significantly greater incidence of poor demarcation of lateral borders than benign melanocytic neoplasms (Spitz naevi and compound naevi) was shown to be without validity on cited empirical grounds as well as theoretical grounds (the lack of constancy of pattern from a 3‐dimensional standpoint).
Differentiation of desquamative interstitial pneumonia (DIP) from pulmonary adenocarcinoma by immunocytochemistry
Authors: Mutton A E , Hasleton P S , Curry A , Bishop P W , Egan J , Carroll K B , Hanley S 
Published: March 2003

AimAfter a misdiagnosis of pulmonary adenocarcinoma as desquamative interstitial pneumonia (DIP), we investigated whether immunohistochemical markers could differentiate these conditions.Methods and resultsThree cases of DIP and one pulmonary adenocarcinoma masquerading as DIP were studied by light and electron microscopy. All cases were mucin‐negative. The cases of DIP were CD68 positive but cytokeratin‐negative. The adenocarcinoma was cytokeratin‐positive (AE1/3 and CAM5.2), as well as showing some CD68‐positive cells. Markers for carcinoma (CEA, Ber‐EP4, and Leu M1) were negative in all cases. Ultrastructurally the adenocarcinoma appeared to be derived from Type II pneumocytes.ConclusionBefore a diagnosis of DIP is made, cytokeratin markers should be used.
Gains and losses of CD44 expression during breast carcinogenesis and tumour progression
Authors: Bànkfalvi À , Terpe H‐J , Breukelmann D , Bier B , Rempe D , Pschadka G , Krech R , Böcker W 
Published: March 2003

AimsThis study was performed to investigate whether the CD44 immunophenotype of breast lesions correlates with the clinical evolution and prognosis of breast cancer.Methods and resultsOne‐hundred and fifty‐two routinely processed normal, benign and malignant breast tissue samples were investigated by the following monoclonal antibodies: CD44 s (F10–44–2), CD44v3 (3G5), CD44v4 (11.10), CD44v5 (VFF‐8), CD44v6 (VFF‐18), CD44v7 (VFF‐9), CD44v9 (11–24) after wet autoclave pretreatment for antigen retrieval. We found that: (1) in normal breast tissues luminal epithelial cells lacked detectable CD44 in contrast to basal cells, which constitutionally expressed CD44 s, v3, v5 v6 and v9 isoforms; (2) in the intraductal compartment of benign hyperplastic lesions, there was scattered or focal staining for CD44 s, v5, v6, v7 and v9 isoforms; (3) in neoplastic lesions restricted neo‐expression of CD44v3 and v4 was detected; and (4) the CD44 immunophenotype of invasive breast carcinomas was influenced largely by differentiation grade, steroid receptor status of the tumours and significantly correlated with metastatic involvement of the axillary lymph nodes.ConclusionsQualitative and quantitative changes of CD44 expression are implicated in early stages of breast carcinogenesis. The restricted neo‐expression of certain CD44 isoforms in breast neoplasias suggests that CD44 might be a potential target for future antibody‐based tumour therapy.
Ovarian hepatoid yolk sac tumours: morphological, immunohistochemical and ultrastructural features
Authors: Devouassoux‐Shisheboran  , Schammel  , Tavassoli  
Published: March 2003

AimThe clinicopathological, immunohistochemical and ultrastructural features of two ovarian hepatoid yolk sac tumours (H‐YST) from our files are reviewed.Methods and resultsUsing avidin–biotin–peroxidase complex technique, the immunoprofile of these tumours was compared to that of a classic yolk sac tumour and to that previously reported for hepatocellular carcinomas. The clinicopathological and morphological features of our cases are similar to the seven previously reported ovarian cases. This rare germ cell tumour occurs in young females (mean age = 17.6 years) and presents most commonly with abdominal pain and a large ovarian mass (average size = 140 mm). Histologically, the tumours display a striking resemblance to hepatocellular carcinoma. The absence of an associated typical pattern of yolk sac tumour or other germ cell neoplasm may make it difficult to recognize the germ cell origin of this lesion. Our cases demonstrated positive staining for alpha‐fetoprotein and alpha‐1‐antitrypsin. In addition, there was immunoreactivity with polyclonal carcinoembryonic antigen (CEA) antiserum in a canalicular pattern, focal staining for inhibin, oestrogen and progesterone receptors and absence of immunoreactivity for CK7 that contrasts with the immunophenotype of a usual yolk sac tumour.ConclusionsOvarian H‐YST and hepatocellular carcinoma share a similar immunoprofile. Ovarian H‐YST is a highly aggressive tumour, most patients exhibit recurrence or die of disease within 2 years of diagnosis.
A novel immunohistochemical detection system using mirror image complementary antibodies (MICA)
Authors: Mangham D C , Isaacson P G 
Published: March 2003

AimsTo describe and illustrate a novel and highly sensitive peroxidase‐based immunohistochemical detection system which employs mutually attractive, mirror image complementary antibodies (MICA).Methods and resultsTo demonstrate the sensitivity of the MICA system alongside the avidin–biotin complex (ABC) method, we selected a range of mouse monoclonal and rabbit polyclonal primary antibodies against antigens that are generally regarded as relatively difficult or impossible to detect on formalin‐fixed, paraffin‐embedded lymphoid tissue. Compared with the ABC method, the MICA immunodetection method enabled us to dilute primary antibodies up to 200‐fold with equivalent or superior immunostaining results and, usually, considerably shortened primary antibody incubation times.ConclusionsWe have described and illustrated a novel immunohistochemical detection system and demonstrated greatly increased sensitivity over the commonly used ABC system. An additional advantage of the MICA system is that it is avidin‐free and so avoids non‐specific staining due to endogenous tissue biotin.
Pleomorphic adenomas of the parotid express different mesenchymal phenotypes: demonstration of matrix gene expression products characteristic of the fibroblastic and chondrocytic cell lineages
Authors: Neureiter  , Böhmer  , Kirchner  , Aigner  
Published: March 2003

AimsPleomorphic adenomas of the salivary glands are characterized by their high tissue diversity. Many studies have explored the derivation and differentiation of the neoplastic cells. We investigated the composition of the collagenous extracellular tumour matrix and could show a specific biochemical composition pattern in the different tumour areas.Methods and resultsIn epithelially differentiated acinar and ductal areas there was positive staining for basement membrane collagen type IV and no, or only scarce, staining for collagen types I, II, III, or VI. Solid areas mostly lacked any extracellular matrix. In areas with fibrous tissue‐like appearance, the fibroblast‐typical interstitial collagen types I, III and VI were seen. Chondroid areas showed abundantly the characteristic cartilage components, collagen type II and, pericellularly, type VI collagen.ConclusionsOur data show the presence of fibroblastic and chondrocytic cell differentiation in pleomorphic adenomas. Thus, they confirm that these neoplasms display, besides epithelial cell types, also real mesenchymal cell and tissue types. Differences in the abundance and the biochemical composition of the extracellular tumour matrix account largely for the morphological heterogeneity of pleomorphic adenomas of the salivary glands.
Primary alveolar soft part sarcoma of bone
Authors: Park  , Unni  , Kim  , Han  , Yang  , Wenger  , Sim  , Lucas  , Ryan  , Nadim  , Nojima  , M Fletcher  
Published: March 2003

AimsAlveolar soft part sarcoma is a distinct, rare soft tissue tumour occurring primarily within the skeletal muscles or musculofascial planes in young adults. Primary involvement of bone is extremely rare. We report on six patients with alveolar soft part sarcoma occurring primarily in bone.Methods and resultsThorough clinical and radiographic examinations were done to rule out any other primary site. The patients were four women and two men aged 17–35 years (mean, 24.5 years). The primary site of the tumour was the femur in three patients, the ilium in one and the fibula in two. In one of the patients with fibular involvement, the tibia was also involved by direct extension. Of the long bone lesions, three were centred in the metaphysis and one in the diaphysis. Radiographically, all of the lesions demonstrated an osteolytic pattern of bone destruction with ill‐defined margins and a wide zone of transition between the lesion and adjacent normal bone. Microscopically, all tumours showed the typical histological pattern of alveolar soft part sarcoma. Diastase‐resistant, periodic acid–Schiff‐positive crystalline structures were identified within the cytoplasm and confirmed ultrastructurally. Immunohistochemically, a keratin stain was negative in all cases; there was positive staining for MyoD1 in the cytoplasm but not the nuclei. Distant metastasis developed in four patients; one died.ConclusionAlveolar soft part sarcoma arising in bone is extraordinarily rare but should be considered in the differential diagnosis of metastatic hypernephroma in a young patient.
Thyroid transcription factor‐1 is the superior immunohistochemical marker for pulmonary adenocarcinomas and large cell carcinomas compared to surfactant proteins A and B
Authors: Kaufmann  , Dietel  
Published: March 2003

AimsAntibodies against the thyroid transcription factor‐1 (TTF‐1) and the surfactant proteins A and B (SPA, SPB) were compared as paraffin‐reactive immunohistochemical markers for non‐small cell carcinomas of pulmonary origin.Methods and resultsWe studied 138 carcinomas of pulmonary origin (98 adenocarcinomas, 20 non‐neuroendocrine large cell carcinomas, 20 squamous cell carcinomas) and a total of 276 extrapulmonary carcinomas of various primary origins. Using the monoclonal antibody 8G7G3/1, TTF‐1 was detectable in 75% of non‐mucinous pulmonary adenocarcinomas and in 40% of large cell carcinomas but in only 10% of mucinous adenocarcinomas and not in squamous cell carcinomas. In contrast, both SPA and SPB were positive in only 45% of pulmonary adenocarcinomas and in 10% and in 5% of the large cell carcinomas, respectively. TTF‐1 had a specificity of 0.98 for pulmonary carcinomas as 5/7 thyroid carcinomas were the only TTF‐1‐positive extrapulmonary tumours. Anti‐SPB and anti‐SPA had specificities of 1.00 and 0.97, respectively.ConclusionsThe monoclonal antibody 8G7G3/1 against TTF‐1 should be the first choice as a component of an antibody panel aiming to prove or to exclude the pulmonary origin of non‐mucinous adenocarcinomas and non‐neuroendocrine poorly differentiated carcinomas, especially in patients presenting with metastatic carcinomas of unknown primary site.
Epstein–Barr virus and gastric carcinoma in Western patients: comparison of pathological parameters and p53 expression in EBV‐positive and negative tumours
Authors: Chapel  , Fabiani  , Davi  , Raphael  , Tepper  , Champault  , Guettier  
Published: March 2003

AimsThe presence of Epstein–Barr virus (EBV) was studied in 56 gastric carcinomas from Western patients by in‐situ hybridization for EBV‐encoded RNAs (EBER). EBV‐positive and negative carcinomas were compared for various pathological parameters including p53 overexpression.Methods and resultsEBERs transcripts were detected in seven cases overall: four cases of 52 conventional carcinomas (7.7%) and three cases of four gastric carcinomas with lymphoid stroma (75%). EBER positivity was diffuse in five cases and restricted to a localized area of the tumour in two cases of conventional carcinoma. A monoclonal EBV genomic pattern was demonstrated in the case tested by Southern blot analysis. By immunohistochemical analysis, neither EBV latent or lytic cycle proteins nor C3d/EBV receptor were expressed by neoplastic cells. EBER positivity was significantly correlated with prominent lymphoid reaction (P = 0.0002) which was associated with numerous PS100‐positive dendritic cells and with HLA‐DR expression by tumour cells (P = 0.03). p53 immunoreactivity in more than 30% of tumour cells was detected in 25 out 49 EBV‐negative cases and was absent in EBV‐positive cases except in one case with focal EBER‐positivity.ConclusionsFocal staining for EBER is an unusual finding in the setting of gastric carcinoma and these results suggest that there might be two types of EBV‐associated gastric carcinoma in which the viral infection will play a different role. The presence of a stromal lymphoid reaction which is strongly correlated with EBV positivity, is associated with antigen‐presenting ability by HLA‐DR‐positive tumour cells or abundant dendritic cells. The function of p53 appears preserved in all EBV‐associated carcinomas except in one case with focal EBER expression whereas the immunohistochemical pattern of p53 is suggestive of a mutational phenomenon in 51% of EBV‐negative cases.