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T Marshall

Publications and source records attributed to T Marshall.

At least 181 records · Page 10Linked to original sources
PubMed1989

Sodium dodecyl sulfate-polyacrylamide gel electrophoresis without a stacking gel: use for high sample throughput.

Sodium dodecyl sulfate-polyacrylamide gel electrophoresis without a stacking gel minimizes lateral spreading of protein when samples are applied in agarose wells and allows high sample throughput (6 samples/cm gel width). The method is simple and convenient to use and gives comparable resolution to the standard method with 4-20% or 6-30% polyacrylamide gradient gels. Best results are obtained when the upper zone of the separating gel is of low polyacrylamide concentration. This indicates a need for the molten agarose to penetrate and anneal with the separating gel.

Electrophoresis, Polyacrylamide Gel↗
PubMed1989

Electrophoresis of human salivary proteins: response to natural stimulation.

Human saliva was analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and the response to different natural stimuli investigated. Serva Blue R revealed pink/violet-staining proteins ("lumicarmines"). These intensified following stimulation but in an unpredictable and sometimes disproportionate manner, causing pattern changes. This variable response undermines their potential forensic value for suspect identification.

Eating↗
PubMed1989

Trans-regulation and differential cell specificity of human papillomavirus types 16, 18, and 11 cis-acting elements.

The noncoding region (ncr) of human papillomavirus (HPV) types 16, 18, and 11 contains promoter and/or enhancer function. We have localized the sequence containing the constitutive enhancers of HPV types 16, 18, and 11 to 315, 230, and 213 bp fragments, respectively, for comparative studies. The region of homology shared between the enhancers of the three viruses is limited to the sequence ATTTTTGGCTT, which is also present in the ncr of HPV 6b and 33. We have also examined the enhancer activity of the HPV ncrs in three human cervical carcinoma cell lines, one noncervical human carcinoma cell line, and one monkey kidney established cell line. We observed cell-specific differences in the constitutive expression of the enhancers in the various cell lines. The conditional enhancer activity of the ncr of the viruses is increased in trans by the E2 gene product of HPV 16. Transactivation by E2 is mediated through the E2 binding motif on HPV enhancer plasmids with a heterologous but not with a homologous promoter. Our preliminary studies also indicate a repressor function for the E7 gene of HPV 16.

Base Sequence↗
PubMed1989

Covert psychiatric disturbance in patients with globus pharyngis.

There is currently little agreement concerning the aetiology of globus pharyngis (née hystericus), and both physical and psychological factors have been suggested as primary causes of this common disorder. Using validated research questionnaires we tested the hypothesis that there is significant psychiatric morbidity in female globus patients but not in males. One hundred and twenty-one globus patients (90F, 31M) were tested on the Crown-Crisp Experiential Index (CCEI), the General Health Questionnaire (GHQ), the Hysteroid Obsessoid Questionnaire (HOQ) and the Eysenck Personality Questionnaire (EPQ). Female globus patients, but not males, have low extraversion scores and high GHQ scores when compared with age- and sex-matched ENT patient controls, and high mean levels of anxiety, depression and somatic concern on the CCEI. In females the mean total CCEI score was not significantly different from the mean of a psychiatric out-patient group. The males had total CCEI scores similar to a group with no psychiatric symptoms. Globus patients did not have hysteroid traits. We conclude that a substantial minority of globus patients has significant psychiatric morbidity. It is important to exclude mild, reactive-type depression and conversion disorder in these patients, in whom invasive physical investigations are inappropriate.

Adult↗
PubMed1989

Nucleolar organiser regions in adenocarcinoma in situ of the endocervix.

The AgNOR technique was used to analyse 11 cases of adenocarcinoma in situ of the endocervix and five examples of healthy cervices to assess whether areas of "increased nuclear activity" could be located adjacent to the malignant tissue. Areas of adenocarcinoma in situ had significantly more AgNOR staining dots than apparently normal bordering areas ("transitional areas") and areas of endocervical epithelium remote from adenocarcinoma in situ. There were no significant differences between AgNOR counts in transitional areas and areas remote from adenocarcinoma in situ, and between these areas and histologically normal cervices. These observations provide no support for the hypothesis that areas of glandular atypia of lesser severity or zones of "increased nuclear activity" exist adjacent to adenocarcinoma in situ.

Adenocarcinoma↗
PubMed1989

Heterogeneity of serum creatine kinase isoenzyme MM in myocardial infarction: clinical significance and post-synthetic conversion of "abnormal" sub-bands.

We investigated the "abnormal" sub-bands of serum creatine kinase (CK; EC 2.7.3.2) isoenzyme MM in acute myocardial infarction (AMI), using isoelectric focusing in polyacrylamide gels, and compared the patterns with those for non-AMI patients and for athletes with increased CK. The "abnormal" sub-bands a (pI 7.55), b (pI 7.35), c (pI 7.25), d (pI 7.05), e (pI 6.85), f (pI 6.72), g (pI 6.50), h (pI 6.40), i (pI 6.28), j (pI 6.20), and k (pI 6.15), in common with "normal" sub-bands 1 (pI 6.91), 2 (pI 6.65), and 3 (pI 6.35), were less uniformly distributed in the AMI and demonstrated a faster rate of anodal conversion than in the non-AMI patients and athletes. "Abnormal" sub-bands a and b were detected only in the AMI patients. Incubation of myocardial CK-MM, predominantly CK-MM 1, with 2-mercaptoethanol, 15 mmol/L, resulted in conversion to the "abnormal" sub-bands b and c. Incubation of myocardial CK-MM with normal serum of low total CK yielded CK-MM 3, which on further incubation with 2-mercaptoethanol, 15 mmol/L, resulted in conversion to the "abnormal" sub-bands f and g. Comparable in vitro incubation of serum from AMI patients gave pattern changes consistent with conversion of CK-MM 1 to b, c; CK-MM 2 to d, e; and CK-MM 3 to f, g.

Adult↗
PubMed1988

Nuclear magnetic resonance and radionuclide angiographic assessment of acute myocardial infarction in a randomized trial of intravenous streptokinase.

Sixty-six patients presenting with their first evolving transmural acute myocardial infarction (AMI) were randomized to receive either streptokinase (n = 41) or placebo therapies (n = 25) within 6 hours of the onset of chest pain. These patients then underwent supine rest, exercise and after-nitroglycerin radionuclide angiography 3 weeks after AMI. Nuclear magnetic resonance (NMR) imaging was performed at 3 weeks as a more direct estimate of AMI size. Although peak creatine kinase values were comparably elevated between groups (2,367 +/- 1,486 IU/liter for streptokinase vs 2,637 +/- 1,305 IU/liter for placebo), there was a significant reduction in NMR-measured AMI size in the streptokinase group (3 +/- 2% of left ventricular volume vs 10 +/- 4% in the placebo group, p less than 0.05). This occurred despite comparable resting (54 +/- 11 vs 47 +/- 10% and exercise (53 +/- 12 vs 49 +/- 11%) global ejection fractions. However, following nitroglycerin, there was an improvement in global ejection fraction in the streptokinase-treated group that was not observed with placebo (61 +/- 13 vs 48 +/- 10%, p less than 0.05). A similar pattern was also observed with regional functional analysis. Thus, streptokinase therapy leads to a significant reduction in NMR-measured AMI size and to a greater degree of reversible left ventricular dysfunction.

Adult↗
PubMed1988

Studies on the expression of Cu,Zn superoxide dismutase in human tissues during development.

The developmental expression of Cu,Zn superoxide dismutase in human lung and erythrocytes has been studied using activity measurements, immunoblotting and immunohistochemistry. Enzyme activity in erythrocytes increased significantly during gestation but no developmental trend was seen in lung. Immunoblotting identified a single enzyme form that was present in a variety of tissues and immunohistochemistry showed the enzyme to have widespread distribution in lung tissue. These data indicate that Cu,Zn superoxide dismutase is consistently expressed during human development and that, unlike in other species, no late-fetal surge in expression occurs.

Cytosol↗
PubMed1988

High resolution two-dimensional electrophoresis and sodium dodecyl sulphate-polyacrylamide gel electrophoresis of cheese proteins after rapid solubilisation.

The proteins of cheese are rapidly solubilised by heating to 95 degrees C in buffered 2% sodium dodecyl sulfate, 5% 2-mercaptoethanol. Electrophoretic analysis of the solubilised proteins by either one-dimensional sodium dodecyl sulphate-polyacrylamide gel electrophoresis or high resolution two-dimensional electrophoresis yields reproducible patterns characteristic of an individual cheese and its extent of ripening. The patterns reveal (i) the residual amounts of milk casein and whey proteins, and (ii) the appearance of casein degradation products, including pink-violet components as detected by Coomassie Blue staining.

Cheese↗
PubMed1988

An evaluation of two-dimensional electrophoresis for detection of human serum proteins in acute myocardial infarction.

High resolution two-dimensional electrophoresis indicates that serum proteins previously only detected in patients with acute myocardial infarction (AMI) (Gomo et al., Electrophoresis 1983, 4, 298-302) are also present in the serum protein patterns of other patients (AMI negative or demonstrating acute phase response) and are faintly detected even in controls. Thus, these proteins are not specific to AMI and are probably acute phase reactants. However, they do demonstrate a characteristic time course response in sequential samples from AMI patients.

Acute-Phase Reaction↗
PubMed1988

Serial nuclear magnetic resonance imaging of acute myocardial infarction with and without reperfusion.

To compare nuclear magnetic resonance (NMR) image-derived T1 and T2 changes during evolving infarction, 14 dogs were studied serially: (1) 1 to 2 hours after left anterior descending coronary occlusion, (2) 2 to 3 hours after coronary occlusion (n = 7) or in the first hour after reperfusion following 2 hours of occlusion (n = 7), and (3) 5 days and (4) 21 days after occlusion/reperfusion. In addition, the extent of T1 and T2 abnormalities was compared to the extent of infarction as determined histologically for each set of images. With sustained coronary occlusion, an increase versus control values (T1 = 351 +/- 11 msec; T2 = 41 +/- 2 msec) was observed in the second hour after occlusion (T1 = 448 +/- 51 msec; T2 = 51 +/- 8 msec), gradually reaching a maximum by day 5 (T1 = 490 +/- 64 msec; T2 = 63 +/- 9 msec). By 21 days, T1 had decreased to 427 +/- 43 msec and T2 to 55 +/- 11 msec. However, with myocardial reperfusion, an abrupt increase in both T1 and T2 occurred compared to prereperfusion values in the first hour after release of occlusion, from 445 +/- 32 msec to 555 +/- 65 msec and from 52 +/- 5 msec to 65 +/- 8 msec, respectively. Subsequently, T1 remained elevated whereas T2 normalized. Only on day 21 images was there a good correlation between the extent of T1 and T2 abnormalities and infarct size, in both nonreperfused (r = 0.87; p less than 0.05), and reperfused (r = 0.89; p less than 0.01) dogs.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1988

Release of lysosomal enzyme beta-glucuronidase from isolated human eosinophils.

The human eosinophil contains lysosomal enzymes that can contribute directly to tissue injury and inflammation. Characterization of lysosomal-enzyme release from the eosinophil has been largely limited to isolates from patients with hypereosinophilia. Because eosinophils from such individuals may not demonstrate normal functional responses, we established a method to obtain purified, normal human eosinophils with a Percoll gradient. With this method, it is possible to isolate eosinophils (95.5 +/- 3.9%) and neutrophils (greater than 99%) in high purity from normal subjects. With these granulocyte isolates, we evaluated and compared release of the lysosomal enzyme, beta-glucuronidase (BG), after cell activation with opsonized zymosan particles. Neutrophils released 33.0 +/- 1.2% (mean +/- SEM; n = 5) of total BG (30 minutes of incubation with zymosan), whereas eosinophil secretion was 24.2 +/- 1.7% (n = 5). The fungal metabolite, cytochalasin B (CB), which inhibits microfilament activity, enhanced BG secretion from neutrophils (33.0 +/- 1.2% to 42.8 +/- 2.8% with CB; p less than 0.01). In contrast, CB had no effect on eosinophil BG release. Interestingly, BG content in eosinophils is 101.2 +/- 3.9 micrograms phenolphthalein per 10(6) cells per 18 hours, which compares to a neutrophil level of 51.0 +/- 3.2 (p less than 0.001). Thus, although eosinophils and neutrophils release a similar percentage of total cellular BG on stimulation with zymosan particles, the absolute amount of enzyme per cell is greater in the eosinophil than in the neutrophil. Study of eosinophil function promises to elicit a more complete insight into its contribution to tissue injury.

Cell Separation↗
PubMed1988

A pathologist's view of terrorist violence.

The experience of the Northern Ireland State Pathology Service is drawn on to illustrate the forensic aspects of death by shooting and bombing caused by terrorists. The investigations into these deaths have to contend with rumours and allegations which can inflame feelings in the community or mislead the investigators and this aspect is dealt with. The conclusion is reached that when terrorist violence erupts there must be a forensic service able to cope and maintain the usual high standards of scientific investigation.

Autopsy↗
PubMed1988

Heterogeneity of serum creatine kinase isoenzyme MM in myocardial infarction: standardization of patterns by use of cord-blood serum.

We investigated serum creatine kinase (CK; EC 2.7.3.2) isoenzyme MM in myocardial infarction, using isoelectric focusing in polyacrylamide gels. As many as 14 sub-band species were detected, and sequential sampling revealed a progressive anodal shift in their distribution. A nomenclature for sub-band typing is proposed. It denotes the major sub-bands as 1 (pl 6.91), 2 (pl 6.65), and 3 (pl 6.35); which are usually detected in sera of normal CK range. Abnormal sub-bands (associated with increases in the concentrations of CK) are denoted as a (pl 7.55), b (pl 7.35), c (pl 7.25), d (pl 7.05), e (pl 6.85), f (pl 6.72), g (pl 6.50), h (pl 6.40), i (pl 6.28), j (pl 6.20), and k (pl 6.15). Cord-blood sera gave highly reproducible CK-MM patterns characterized by prominent detection of sub-bands 1-3 and faint detection of c, e, f, g, h, i, and j. It is recommended as a standard for CK-MM sub-band typing.

Creatine Kinase↗