Search PubMed⌕ Search

Biomedical subjects

W E Taylor

Publications and source records attributed to W E Taylor.

34 records · Page 2Linked to original sources
PubMed1987

Use of scanning electron microscopy and energy dispersive X-ray analysis (SEM-EDXA) in identification of foreign material on bullets.

The authors report two cases in which examination of foreign material embedded in or adherent to bullets provided critical information in the reconstruction of a crime scene. Analysis of small particles by scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDXA) can be accomplished without destruction or injury of the particles. In one case, the detection and identification of mineral fragments embedded near the nose of a bullet provided conclusive evidence that the bullet had ricocheted from a fireplace before striking the victim. In the second case, analysis of particles from two bullets identified them as them as bone fragments, thus proving which shots fired from a police officer's gun had killed a suspected burglar. SEM-EDXA has not been widely used to identify such material on bullets, but should be considered a potentially powerful tool in forensic science.

Adolescent↗
PubMed1985

Stringent response in Escherichia coli induces expression of heat shock proteins.

The rpoD gene (encoding the 70,000 Mr sigma subunit of Escherichia coli RNA polymerase) is the most distal gene in an operon that contains three genes. The promoter-proximal gene is rpsU (encoding ribosomal protein S21) and the middle gene is dnaG (encoding DNA primase). During the stringent response, caused by a deficiency in an aminoacyl-tRNA, expression of rpsU is decreased, while expression of rpoD is not. This disco-ordinate regulation is due to increased transcription from a minor promoter upstream from rpoD, in the dnaG gene. Transcription from this promoter is also increased during the heat shock response. Expression of other heat shock proteins was found to increase during the stringent response. Thus, the stringent response in E. coli induces expression of heat shock proteins. The requirements for this stringent induction of the heat shock proteins differ from those for temperature induction during the heat shock response.

Base Sequence↗
PubMed1984

Transcription from a heat-inducible promoter causes heat shock regulation of the sigma subunit of E. coli RNA polymerase.

The rpoD gene encoding the sigma subunit of E. coli RNA polymerase is cotranscribed with rpsU and dnaG, encoding ribosomal protein S21 and DNA primase, respectively. After temperature upshift, a heat shock promoter (Phs) located within dnaG is transiently induced, causing increased transcription of rpoD. The extent of induction is sufficient to account for the heat shock response of sigma synthesis. The initiation site of this promoter was located about 360 bp upstream of rpoD by promoter cloning and S1 nuclease mapping. Plasmid deletions generated with Bal 31 nuclease show that the DNA sequence CTGCCACCC in the -44 to -36 region of this promoter is necessary for its heat shock activity. Heat induction of transcription from Phs is under the control of HtpR, a positive regulator of the heat shock response.

Base Sequence↗
PubMed1983

Renal cell carcinoma and systemic amyloidosis: demonstration of AA protein and review of the literature.

A case of renal cell carcinoma associated with systemic amyloidosis in a patient with nephrotic syndrome is presented. Amyloid deposits were present in the resected tumor, ipsilateral kidney, and spleen. Potassium permanganate treatment of histologic sections as well as immunoperoxidase staining identified AA protein within the amyloid. Surgical removal of the tumor caused marked remission of the patient's proteinuria. Thirty-nine previously reported cases of renal cell carcinoma with amyloidosis are reviewed. Most tumors have clear cell histologic features, and the amyloid distribution follows the "secondary" pattern. A possible mechanism of amyloid production in renal cell carcinoma is presented in which the tumor directly or indirectly participates in the modification of SAA protein into a precipitable form.

Adenocarcinoma↗
PubMed1983

Xanthogranulomatous pseudotumor of the vagina: evidence of a local response to an unusual bacterium (mucoid Escherichia coli).

Utilization of nonconventional bacterial strains and electron microscopy occasionally may aid in the recognition of unusual microorganisms which fail to be demonstrated by more conventional bacterial stains. We report an unusual case of recurrent vaginal polyps, initially thought by physical examination to represent a malignant neoplasm and histologically to represent a granular cell tumor. The lesions were comprised microscopically of sheets of large, polygonal, histiocytic-like cells with abundant eosinophilic granular cytoplasm. With the Dieterle silver stain, the cytoplasm of these cells contained large numbers of intracellular rod-shaped bacilliform bodies thought to be microorganisms. These organisms stained not at all or very poorly with more conventional bacterial stains, such as Gram and Giemsa stains. Electron microscopy was employed to confirm the presence of intra- and extracellular bacilliform bodies and the absence of large numbers of cytosegresomes, the latter characteristically seen in typical granular cell tumors. Cultures of tissue from the biopsy documented a pure strain of a mucoid form of Escherichia coli. We were unable to identify any prior report describing a similar recurrent inflammatory vaginal lesion in which mucoid E. coli was demonstrated. We discuss possible pathogenesis of this case, and relate it to morphologically similar diseases, such as Whipple's disease and malakoplakia, in which there appears to be defective clearance of bacteria from a variety of tissues.

Aged↗
PubMed1982

Acute suppurative thyroiditis in children.

The ability of the thyroid gland to withstand infection is a well known phenomenon. In this regard, inflammatory disease of the thyroid gland in children is an uncommon occurrence. The frequency with which this proceeds to abscess formation is rare. Review of the literature of the past 25 years reveals only 21 reported cases of acute suppurative thyroiditis in children, only one of which has been reported in the otolaryngologic literature. We report two cases of thyroid abscess in children initially presented as painful swellings in the lower neck. An overview of the management of these patients is detailed, including a discussion of the appropriate utilization of diagnostic studies. Demonstration of an internal fistula originating from the pyriform sinus underscores the need to consider a fourth branchial arch remnant as a possible source of infection. The importance of obtaining appropriate bacterial, fungal, and acid-fast cultures is stressed, as is the role of antibiotic therapy and definitive surgery once the diagnosis of thyroid abscess is made.

Abscess↗
PubMed1980

WinRho: Rh immune globulin prepared by ion exchange for intravenous use.

An Rh immune globulin [Rh IgG] for intravenous use, WinRho, has been prepared by the Winnipeg Rh Institute by a modification of the ion-exchange column method of Hoppe and colleagues. When administered to Rh-negative male and nonpregnant female volunteers WinRho was found to be nonpyrogenic, nontoxic, safe and protective against Rh alloimmunization. In a clinical trial with 240 microgram given at about 28 weeks' gestation and 120 microgram given after delivery to Rh-negative women at risk of Rh immunization WinRho was effective in preventing Rh immunization. Of the 870 women carrying Rh-positive fetuses who were treated with WinRho during pregnancy and were not tested several months after delivery 14 would have shown evidence of Rh immunization by the time of delivery if WinRho had been ineffective; none showed such evidence. Of the 1122 women carrying Rh-positive fetuses who were retested 4 to 6 months after delivery 83 would have shown evidence of Rh immunization at that time if WinRho had been ineffective; only 1 showed such evidence. The efficiency of yield of anti-D with the modified method of production, the fct that it can be given intravenously (a route that causes the patient less discomfort and immediately results in high anti-D levels) and the lower levels of contaminating IgA and IgM make WinRho the preparation of choice for preventing Rh immunization.

Chromatography, Ion Exchange↗
PubMed1979

Escherichia coli RNA polymerase binding and initiation of transcription on fragments of lambda rifd 18 DNA containing promoters for lambda genes and for rrnB, tufB, rplC,A, rplJ,L, and rpoB,C genes.

Promoters of genes for bacteriophage lambda and for Escherichia coli ribosomal RNA (rrnB), elongation factor Tu (tufB), ribosomal proteins L11 (rplK), L1 (rplA), L10 (rplJ), and L7/L12 (rplL), and RNA polymerase subunits beta (rpoB) and beta' (rpoC) were studied by use of two types of filter binding assays which measured E. coli RNA polymerase binding and initiation of transcription on restriction fragments of lambda rifd 18 DNA. The DNA fragments selectively retained on filters were eluted, concentrated, and analyzed by gel electrophoresis. The binding characteristics of these promotor fragments were qualitatively determined by varying the RNA polymerase, salt, and glycerol concentrations in the polymerase binding assay with HaeIII fragments of lambda rifd 18 DNA. The approximate map locations of these small HaeIII fragments were determined by HaeIII digestion of the larger, previously mapped EcoRI, HindIII, and SmaI restriction fragments of the phage DNA. The base compositions proximal to the 5' ends of mRNA's from promoters on these DNA fragments were elucidated by the polymerase initiation assay, in which the addition of various combinations of nucleoside triphosphates to the reaction allowed RNA polymerase to form high-salt-resistant initiation complexes with some of the known SmaI + EcoRI, EcoRI + HindIII, or HaeIII restriction fragments of lambda rifd 18 DNA. The data obtained by this technique are consistent with the map positions and 5' mRNA base sequences of the known lambda promotors p'R, po, pR and pL. In the main focus of this work, we have determined the approximate map locations and 5' mRNA base compositions of several promoters for known E. coli genes including rrnB, tufB, rplK,A, and rplJ,L. No promoter was detected between rplL and the rpoB,C genes. Thus our data are consistent with the conclusion of Yamamoto and Nomura (1978) that the beta and beta' mRNA is probably cotranscribed from the promoter for rplJ,L. Finally, the approximate map positions and the NTP combinations which initiated transcription of several unknown lambda and E. coli in vitro promoters are reported. The methods reported should prove useful for studying the characteristics of promoters on other cloned DNA regions.

Bacteriophage lambda↗
PubMed1979

Isolation and characterization of transducing phage coding for sigma subunit of Escherichia coli RNA polymerase.

A transducing phage has been isolated with codes for the sigma subunit of Escherichia coli RNA polymerase. Transducing phage were selected from E. coli shotgun collections of HindIII or Sac I fragments cloned into Charon 25, a new bacteriophage lambda vector that is capble of forming lyosogens at high temperature. Transduction of an E. coli strain carrying a temperature-sensitive mutation in the sigma gene was used for the selection. The positions of restriction sites for Sac I, HindIII, Xho I, Bgl II, and Kpn I in the cloned bacterial DNA segments were determined. Phage containing the HindIII fragment complement both primase (dnaG) and sigma (rpoD) whereas those containing the Sac I fragment complement only sigma. Results of analyses of the proteins made both in vivo after infection of UV-irradiated cells and in vitro in a coupled transcription/translation system suggest that a Sac I site separates the promoter for sigma from the sigma structural gene. The direction of transcription of sigma was determined to be clockwise with respect to the E. coli genetic map.

Bacterial Proteins↗
PubMedDate not supplied

Primary pulmonary hypertension: an unusual case associated with extrahepatic portal hypertension.

A patient with both extrahepatic portal hypertension and primary pulmonary hypertension is reported. The pulmonary hypertension developed without a surgical portal-systemic shunt, and at autopsy there was no evidence of a large spontaneous shunt. This association of pulmonary arterial hypertension and portal venous hypertension without either intrinsic liver disease or a large portal-systemic anastomosis has not been reported previously. Our case supports the concept that portal hypertension with its attendant portal-systemic collateral circulation may be the major predisposing cause of pulmonary hypertension both in intrinsic liver disease and extrahepatic portal vein obstruction.

Adolescent↗
PubMedDate not supplied

Barium sulfate crystals in a fine needle aspiration biopsy specimen from a neck mass in a patient with squamous cell carcinoma. A case report.

A fine needle aspirate of a neck mass in a 79-year-old man with a previous laryngectomy for squamous cell carcinoma was submitted for examination. In addition to cytologic findings of squamous cell carcinoma, there were numerous birefringent crystals of varying shapes and sizes. Energy dispersive x-ray analysis confirmed that these crystals were barium sulfate. Recognition of barium sulfate crystals in a fine needle aspiration or other cytologic specimens is important since barium granulomas may mimic neoplasms clinically. Barium sulfate may also indicate rupture of an organ or the presence of a fistula.

Aged↗