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Biomedical subjects

W Wei

Publications and source records attributed to W Wei.

At least 199 records · Page 11Linked to original sources
PubMed1992

Direct chromosome analysis of seven primary colorectal carcinomas.

Chromosome studies were performed on direct preparations of seven cases of primary colorectal carcinomas. Two cases had relatively simple chromosome changes: 48,XY,+8,+21/51, XY,+8,+9,+10,+i(17q),+21, and 47,der(X)t(X;14)(q11;q11)-Y,t(6;18)(p22;q24)+7,+8,der(19)t (19;?)(q13;?). The five others had complicated deletions and translocations; 1p- was noted in five cases, and i(17q) was noted in three cases.

Adenocarcinoma↗
PubMed1991

Nasopharyngeal carcinoma and lymphoinfiltration.

Originally referred to as 'lymphoepithelioma', undifferentiated and poorly differentiated nasopharyngeal carcinoma (NPC) tissues showed intense lymphoinfiltration. In a study of cryosections from 15 NPC tissues, we found that infiltrating lymphoid elements were comprised predominantly of lymphocytes, but plasma cells, follicular dendritic cells, and eosinophils were also commonly seen. Subpopulations of lymphocytes having the same phenotypes tend to aggregate, forming clusters or secondary follicles in stromatous tissues. The tumor areas were mainly infiltrated by T cells. Tumor cells and/or apparently normal epithelium in the paratumorous areas frequently expressed CD21, CD23, CD40 and a B lymphocytes carcinoma cross-reacting antigen (BLCa), all of which are involved in B cell activation and proliferation. CD21 and BLCa were strongly expressed near the surface of both squamous and columnar epithelium by those epithelial cells which are at advanced stage of differentiation, while CD40 was expressed by epithelial cells at earlier stages of differentiation located at or near the basement membrane. CD23 was mainly expressed by columnar cells and basal cells underlying squamous epithelium, but not, or weakly so, by flattened squamous cells or reserve cells underlying columnar epithelium. The large majority of tumor cells expressed CD40 and BLCa. A substantial proportion of them also expressed CD23, but the tumor cells were not reactive for CD21. Despite eosinophilic infiltration, IL-6 was not detected in tumor tissues. IL-1 was, however, detected in abundance in the cytoplasm of follicular dendritic-like cells and in the intercellular spaces in tumor areas and surrounding stromatous tissues. The immunobiology of NPC is discussed in the light of these observations.

Antibodies, Monoclonal↗
PubMed1991

Functional tagging of regulatory elements in the plant genome.

In comparison with animals, relatively few plant genes have been identified that have been shown to be under organ-, tissue- or cell-type-specific regulation. In this paper, we describe how the beta-glucuronidase (GUS) reporter gene (gusA or uidA), fused to a weak promoter (a truncated (-90 bp) CaMV35S promoter), can be used to identify tissue-specific markers in transgenic tobacco plants. The rationale was that the expression of gusA would be determined primarily by position effect. Quantitative analysis revealed that, of 184 -90-gus transgenic plants, 73% exhibited gusA gene activation in leaf tissue, and the level of GUS enzyme activity varied over a 300-fold range within the population. In comparison, transformation with a promoterless gusA gene resulted in GUS expression in 78% of all plants analyzed (in leaf and/or root) and expression levels were three-fold or more lower. Qualitative GUS analysis of single locus -90-gus transformants revealed differential expression in diverse tissues. The spatial pattern of GUS activity was unique to individual transformants, was a reflection of differential gusA gene transcription, and was stably transmissible to progeny. Evidence for preferential expression in roots not only of the -90-gus, but also the promoterless gusA gene is presented. The value of the -90 bp promoter-gusA sequence, which is termed an 'interposon', as a tool both to identify native enhancer sequences in situ and to investigate position effects in plants, is discussed.

Enhancer Elements, Genetic↗
PubMed1990

Simultaneous identification of viral proteins and nucleic acids in cells infected with Aleutian mink disease parvovirus.

A method combining in situ hybridization and immunohistochemistry was used to characterize cells infected with Aleutian mink disease parvovirus (ADV). Single-stranded RNA hybridization probes specific for obligate replicative intermediates and antisera specific for virion or non-structural proteins were employed. Crandell feline kidney cells in which the ADV-G strain of ADV was permissively replicating contained virion and non-structural proteins, large amounts of single stranded virion DNA, duplex replicative form (RF) DNA, and mRNA. Late in the infectious cycle, however, cells containing non-structural proteins but little nucleic acid were observed, probably representing cells in the end stage of viral cytopathology. Sections of lung prepared from mink kits infected with the ADV-Utah 1 strain were then examined. Alveolar type II cells permissively replicating ADV contained viral nucleic acids and proteins in patterns nearly identical to CRFK cells, suggesting that permissive ADV replication was similar in vitro and in vivo. Another population of ADV containing cells that had cytoplasmic virion antigen, but undetectable levels of non-structural protein was found in vivo. Furthermore, although virion DNA was present in the cytoplasm of these cells, RF DNA or mRNA could not be detected. These cells may have been alveolar macrophages sequestering viral particles.

Aleutian Mink Disease Virus↗
PubMed1990

A synergism of antigen challenge and severe magnesium deficiency on blood and urinary histamine levels in rats.

The effects of severe and moderate magnesium (Mg) deficiency on blood and urinary histamine were studied in 36 male weanling Sprague-Dawley rats with or without IgE-stimulating antigen challenge. The rats were divided into six groups: two each on 50 (severely deficient), 300 (moderately deficient), and 2000 (control) ppm Mg diets without and with immunization with ovalbumin challenge on days 0, 14, and 29. Unimmunized severely Mg-deficient rats had significantly elevated urinary histamine which returned to normal by 22 days, but whole blood histamine was still significantly elevated at 36 days. Both blood and urinary histamine of immunized severely Mg-deficient rats were significantly higher than those of all the other groups throughout the study, particularly after the antigen challenge. There was a synergism of antigen challenge and severe Mg deficiency on blood and urinary histamine levels. The results suggest that severe Mg deficiency can aggravate diseases which are caused by abnormal histamine release after exposure to an IgE-stimulating antigen.

Animals↗
PubMed1990

Nucleotide sequence of the 5'-terminal palindrome of Aleutian mink disease parvovirus and construction of an infectious molecular clone.

The 5'-terminal palindrome of the ADV-G strain of Aleutian mink disease parvovirus (ADV) was molecularly cloned and sequenced. A full-length molecular clone of ADV-G, denoted pXVB, was then constructed. When this clone was transfected into cell cultures, infectious ADV could be rescued. Virus derived from pXVB was nonpathogenic for adult mink, as is the parent ADV-G strain.

Aleutian Mink Disease Virus↗
PubMed1987

Regional chemotherapy through a saphenous vein graft for the treatment of head and neck cancers.

Regional chemotherapy was given through a vein grafted between the common carotid and external carotid arteries to 20 patients who had a variety of advanced head and neck cancers. The objective response rate was 73.6%, which included 36.8% complete response. The median duration of response was more than 10 months. The toxicity was mild and well tolerated. The complication rate associated with the procedure was low. This form of regional chemotherapy has significant advantages over the conventional form that uses drugs given through the retrograde temporal artery because the catheter-related complications are eliminated, the perfusion of the tumor can be maintained consistently, and, consequently, the response rate is high and the duration of response is increased.

Adult↗
PubMed1987

Oestradiol binding activity in rat liver tumours and in human hepatocellular carcinoma.

Oestradiol binding activity was studied in normal liver tissues of rats as well as in experimentally induced liver tumours by incubating a cytosol prepared from the tissue with radioactive oestradiol. The free radioactive hormone was absorbed by a dextran-charcoal suspension, and the amount required to saturate the receptors was calculated by a Scatchard plot. Similar activity was observed in normal human liver as well as naturally occurring hepatocellular carcinoma.

Animals↗
PubMed1986

Parapharyngeal space tumours.

Tumours in the parapharyngeal space have been difficult diagnostic and management problems. Consideration of the anatomy in three dimensions may be illustrated with computed tomography. Fifteen patients with parapharyngeal space tumours are presented, including six salivary gland tumours, four neurogenic tumours and five tumours from miscellaneous origin. The tumours were all treated by surgical excision. The preferred approach was the transcervical route. Additional procedures, including total conservative parotidectomy, were carried out depending on the pathology. Mandibulotomy was required for only one patient whose tumour had infiltrated the base of the skull and extended intracranially.

Adenoma↗