Search PubMed⌕ Search

Biomedical subjects

R K Wilson

Publications and source records attributed to R K Wilson.

87 records · Page 5Linked to original sources

Bob's by-lines.

Explore the source record for details and available documents.

Language↗

Clinical implications of a "nonspecific" transbronchial biopsy.

The diagnostic accuracy of transbronchial biopsy via fiberoptic bronchoscope was reviewed in 127 noncritically ill patients. Biopsy results were analyzed according to whether a "specific" pathologic diagnosis of neoplasm, granuloma or pneumonia, or a "nonspecific" diagnosis of inflammation, fibrosis or normal lung was made. The clinical significance of a "nonspecific" biospy specimen was evaluated by clinical follow-up of at least 12 months (mean 15 months) and by grouping patients according to the type of abnormality found on chest roentgenography. Clinical follow-up was available in 119 of these patients. The over-all "specific" diagnostic yield for biopsy with secretions was 49 per cent, with transbronchial biopsy being the sole means of specific diagnosis in 14 per cent of the patients with a peripheral mass lesion, in 18 per cent of the patients with localized infiltrative processes and in 52 per cent of the patients with diffuse infiltrative processes. In 64 (52 per cent) patients both biopsy specimens and secretions were diagnostically nonspecific. In 16 (77 per cent) patients with peripheral mass lesions but nonspecific biopsy findings and secretions, neoplasm was diagnosed by more invasive procedures. However, 22 (91 per cent) patients with localized and 12 (75 per cent) patients with diffuse infiltrative processes had benign clinical follow-up suggesting that open lung biopsy in such patients should be reserved for patients with obvious clinical or roentgenographic evidence of deterioration.

Biopsy↗

Evaluation of transbronchial biopsy of the lung.

Transbronchial biopsy of the lung through the fiberoptic bronchoscope is becoming a widely utilized clinical diagnostic technic. The authors reviewed the histologic features of 109 consecutive cases. The primary problem is the small size of the pulmonary tissue samples obtained, which is further compounded by an apparent mechanical inability to enter the biopsy forceps into dense nodules of neoplastic tissue. The diagnosis of carcinoma can best be made by examining the periphery of the cancer for microscopic extension into adjacent pulmonary parenchyma; however, multiple levels of the tissue block are needed to find such foci. A second problem reflects the use of transbronchial biopsy in the early clinical evolution of various infectious diseases in which pulmonary tissue may contain organisms without a fully developed inflammatory response, which would ordinarily provide the clue to the infective agent. The latter problem appears in cases of infections by Pneumocystis carinii. Close cooperation between the clinician and the pathologist is particularly important in all of these clinical situations.

Biopsy↗

Human epidermal growth factor receptor cDNA is homologous to a variety of RNAs overproduced in A431 carcinoma cells.

The recently discovered similarity between the human epidermal growth factor (EGF) receptor and the avian erythroblastosis virus v-erb-B protein supports the hypothesis that viral oncogenes share a common evolutionary origin with genes encoding growth-regulating cell-surface receptors. To elucidate the relationship between receptors and malignant transformation, we have now used a fragment of v-erb-B as a probe to screen a cDNA library of mRNA from A431 human carcinoma cells, which possess a large number of EGF receptors. Of the six clones isolated, the largest (pE7) contains an insert of 2.4 kilobase pairs (kbp) whose deduced amino acid sequence is homologous to the v-erb-B protein and identical to reported EGF receptor peptide sequences. This pE7 cDNA hybridized to three prominent RNAs of approximately 10, 5.6 and 2.9 kilobases (kb), and to three minor species of 6.3, 4.6 and 3.3 kb. All were present in elevated levels in A431 cells. The prominent 2.9-kb RNA was homologous only to the 5' portion of the pE7 insert. This result raises the possibility that differential RNA processing is used by A431 cells to generate a variety of RNAs.

Amino Acid Sequence↗

An evaluation of several blood transfusion filters.

Several blood transfusion filters designed to remove microemboli were evaluated for filtration and flow characteristics, as well as for hemolysis and for release of particulate debris from the filter. The Dacron wool filter, a depth filter, was superior at removing microemboli measured with an electronic particle size analyzer. A 25 micrometer pore mesh filter was least effective at removing microemboli from stored blood, but demonstrated the most favorable flow rates and induced no apparent red blood cell destruction during filtration. In general, filter efficiency and filter induced hemolysis correlated inversely with flow rate. No filter tested released significant quantities of particulate debris when compared with unfiltered isotonic saline.

Blood Transfusion↗

Mitochondrial gene organization and expression in petunia male fertile and sterile plants.

In cytoplasmic male-sterile Petunia lines, NADH dehydrogenase subunit 3 (nad3) and ribosomal protein S12 (rps12) are cotranscribed with the chimeric gene pcf and located in the region of the mitochondrial genome associated with cytoplasmic male sterility (CMS) in Petunia. In fertile Petunia line 3704, the genes for nad3 and rps12 are cotranscribed with an unidentified open reading frame (orf143). In the homologous region of fertile line 3699, there is an ORF that lacks a genomic DNA-encoded stop codon; instead an RNA editing event creates a stop codon, resulting in an ORF of 161 codons. While expressed sequences homologous to this open reading frame can be detected in sterile lines, a contiguous orf143/orf161 gene does not exist in the CMS-encoding mitochondrial genome. Transcription at the CMS-associated pcf locus and the fertile orf143/nad3/rps12 locus is complex, with multiple 5' and 3' termini. The presence of the nuclear fertility restorer gene affects the abundance of a transcript class with 5' termini--121 nucleotides before the pcf start codon, and greatly reduces the abundance of a pcf gene product with apparent molecular mass of 25 kDa which is present in both vegetative and reproductive tissues of CMS plants. In addition to the 25 kDa protein product, small amounts of precursor and processed pcf products with higher molecular mass have been detected; their possible role in the CMS phenotype is unknown. Current hypotheses for the mechanism of action of CMS-associated and fertility restorer genes are discussed.

Amino Acid Sequence↗