Search PubMed⌕ Search

Biomedical subjects

A Williams

Publications and source records attributed to A Williams.

At least 487 records · Page 27Linked to original sources
PubMed1989

Sequential flow cytometric analysis of cell-cycle related changes in LFA-1 (CD18/CD11a) expression by trisomy 21 (Down's syndrome) lymphoblastoid cells.

Lymphocyte function associated antigen 1 (LFA-1) is a heterodimeric leucocyte adhesion molecule comprising non-covalently associated 95 kD, CD18 and 180 kD, CD11a subunits. Lymphoblastoid cell-lines (LCL) derived from persons with Down's syndrome (Trisomy 21) exhibit increased expression of LFA-1 compared with normal LCL. Although this is probably due to a gene-dosage related increase in the synthesis of CD18, cell-cycle differences between Trisomy 21 (T21) and normal LCL could also influence LFA-1 expression. We have therefore analysed expression of CD18 on G1 and G2M cells using sequential flow cytometry. T21 and normal LCL were co-stained with the DNA-binding vital dye HO342 (Hoechst 33342), and with a CD18 monoclonal antibody. The LCL were first sorted on the basis of HO342 staining into G1 and G2M populations, and these fractions then analysed for CD18 expression. Irrespective of the stage of the cell-cycle, expression of CD18 was increased on T21 compared with normal LCL. Although more CD18 was detected on both T21 and normal G2M compared with G1 cells, the relative density of CD18 in G2M was less than in G1 because G2M cells were larger.

Antigens, CD↗
PubMed1989

Binding of anti-EMA, AGF 4:48 and the lectin UEA-1 to human ovarian carcinomas: histological and clinical correlations.

The staining reactions of the monoclonal antibodies anti-EMA, AGF 4:48 and the lectin UEA-1 from Ulex europaeus were investigated in formalin-fixed, paraffin-embedded sections of 36 primary ovarian carcinomas. The staining patterns were graded and related to tumour type, differentiation, FIGO stage and patient survival. Both antibodies and UEA-1 showed variations in their staining between and within tumours. The staining of mucinous tumours using anti-EMA was significantly less than in non-mucinous tumours. No other significant associations were found between staining grade and the different variables under study. The variations in staining were not demonstrated to have any prognostic significance.

Adenocarcinoma, Mucinous↗
PubMed1989

Ocular toxicity of desferrioxamine--an example of copper promoted auto-oxidative damage?

Three patients with rheumatoid disease were given the 'iron chelating' drug desferrioxamine (DFX), which also has an appreciable affinity for copper. The drug was injected cautiously, in lower doses than in patients with thalassaemia, and intramuscularly to evaluate its anti-inflammatory effects. Two of the three patients developed ocular abnormalities. One patient, who also received methyldopa, developed severe but reversible visual failure associated with an abnormal electro-oculogram (EOG); another showed reversible depression of the EOG. Analysis of the cerebrospinal fluid (CSF) of this patient showed an increase in phenanthroline detectable (non-caeruloplasmin-bound) copper. Analysis of the CSF of the third patient, who did not develop any clinical or electrophysiological ocular abnormalities, was normal. Haematological assessments indicated that all three patients probably had reduced iron stores. With in-vitro systems DFX was shown to mobilise copper from albumin and to facilitate copper movement across a cell membrane model, a property that was enhanced by methyldopa. Our observations are consistent with the concept that in rheumatoid patients low iron stores may result in binding of copper by DFX and that this may be of central importance in causing the ocular toxicity of DFX.

Aged↗
PubMed1989

IgG and IgE antibodies after immunotherapy with bee and wasp venom.

IgG and IgE antibody levels have been followed for a period of 2 years in patients receiving immunotherapy with bee and wasp venom. 106 adult patients who had had anaphylactic reactions to wasp stings had initially low IgG antibody levels to wasp venom which rose with therapy (p less than 0.001). IgE antibody levels also showed an initial rise but subsequently fell (p less than 0.001). The pattern was similar to that previously reported in children who had had anaphylactic reactions to bee stings, but who, after a course of immunotherapy, were able to tolerate stings with impunity. 60 adults who had had anaphylactic reactions to bee stings showed a different pattern, with initially high IgG antibody levels which did not rise further. Since two thirds of this group were beekeepers or members of beekeeper's families, the high initial IgG antibody levels could have been a response to the frequent stings to which such individuals are prone. The fact that high levels did not protect against anaphylaxis shows, however, that the classical concept of 'blocking antibody' is in need of revision.

Bee Venoms↗
PubMed1989

Supervision of pastoral volunteers.

Pastoral care in hospitals can be enhanced by the use of trained volunteer lay people from a variety of backgrounds. God can use all these different personalities as a channel of His love and grace to the sick, injured, and their families. This article summarizes the chaplain's role with initial preparation, training, coordination, and recognition and support of such volunteers.

Chaplaincy Service, Hospital↗
PubMed1989

Human pharmacokinetics of samarium-153 EDTMP in metastatic cancer.

Samarium-153 ethylenediaminetetramethylene phosphonic acid ([153Sm]EDTMP) has been proposed to palliate pain resulting from osteoblastic metastatic bone cancer. Encouraging results in dogs with primary malignant bone cancer provided the catalysis for human biodistribution studies in five patients with metastatic skeletal carcinoma. The objective was to assess the preferential localization of [153Sm]EDTMP in bony lesions and compare it to the 99mTc-labeled phosphonates. Blood clearance of [153Sm]EDTMP was rapid with minimal accumulation in nonosseous tissues. Both radiopharmaceuticals showed identical lesion uptake in 23 paired lesions (p greater than 0.05). This indicates that the two radiopharmaceuticals concentrate in metastatic skeletal lesions by the same mechanism and since [153Sm]EDTMP emits beta radiation it may be therapeutically useful in ameliorating metastatic bony cancer pain.

Aged↗
PubMed1989

Interaction between cortisol and microbial proteases.

Binding (or interaction) of cortisol with microbial molecule(s) was observed by employing Bio-Gel HTP affinity chromatography and subsequently by fluorescence spectrophotometry. Molecule(s) in the crude extract of baker's yeast and in other microbial proteases exhibited varied degrees of cortisol-binding. Bacterial protease (type IX) had highest, while the type XXVI enzyme had the lowest, binding capacity. In addition, these two proteases exhibited a distinct difference in the alterations of ultraviolet spectra due to interaction with cortisol. Using casein as a substrate, cortisol, CTP, trypsin inhibitor or leupeptin appreciably inhibited type IX protease at low concentrations of Ca2+. However, thyroxine had no effect on this protease.

Bacteria↗
PubMed1988

Experimental charge measurement at leaving oxygen in the bovine ribonuclease A catalyzed cyclization of uridine 3'-phosphate aryl esters.

The title esters are demonstrated to be specific substrates of bovine pancreatic ribonuclease A (EC 3.1.27.5). The Brønsted dependence of kcat/Km at pH 7.50 for the enzyme-catalyzed cyclization versus the pKa of the leaving phenol exhibits two regression lines of almost identical slope for respectively 2-chlorophenols and 2,6-unsubstituted phenols: log kcat/Km = -0.20 pKa ArOH + 5.47 (n = 5, r = 0.957); log kcat/Km = -0.17 pKa ArOH + 5.79 (n = 4, r = 0.965). Comparison of the Brønsted beta 1g's with that for the standard reaction where imidazole catalyzes the cyclization (beta 1g = -0.59) indicates considerably less development of negative charge on the leaving oxygen in the enzyme case, providing experimental evidence for the hypothesis that electrophilic assistance is involved in catalysis. The existence of two essentially parallel Brønsted correlations is not reflected in the standard reaction of substrate with imidazole. Modeling studies indicate that the phenyl ring of the substrate can take up a range of positions away from the active site; the presence of ortho chloro substituents considerably restricts the motion of the phenyl leaving group.

Animals↗
PubMed1988

The clinical value of measuring immunoglobulins when assessing penicillamine therapy in rheumatoid arthritis.

Immunoglobulins are often high in active rheumatoid arthritis and fall when treatment with a slow-acting anti-rheumatic drug is instituted. We assessed the value of monitoring immunoglobulins during penicillamine therapy; 145 patients were followed for up to 5 years, IgA, IgM and IgG levels were compared to 12 other clinical and laboratory variables on 903 occasions. Mean levels of IgA and IgG fell by 10-30%. These changes were less than with ESR or clinical measures such as articular index and duration of morning stiffness. Immunoglobulin levels showed weak correlations with other variables. Only a small number of patients had hypogammaglobulinemia. Initially, 5 cases had low IgA with subsequent falls in 3 more. Initially, 2 cases had low IgG with subsequent falls in 5 more. No patients had low IgM levels. These changes seemed clinically irrelevant. Radiological progression was related to IgA levels. Patients with persistently high rates of radiological progression had persistently higher serum IgA. We conclude that IgM gives the most "acute phase" pattern of response. IgA gives more theoretically interesting information, especially concerning radiological progression. There is only a limited amount of clinically valuable information gained from measuring immunoglobulins.

Adult↗
PubMed1988

Priority setting in public and private health care. A guide through the ideological jungle.

Priority setting means deciding who is to get what at whose expense. In the context of health care, the 'what' is that statement refers to different sorts of health care, and the 'who' to different sorts of people. The 'whose expense' is not so straightforward. It appears to refer to 'who will pay the bill', and in a public health care system this might seem to be the government, though behind the government stands the taxpayer, and that means all of us. Even in a private health care system it is rarely the patient who meets the bill directly, for some or all of it will be met by an insurer, and the costs of any particular treatment episode will be spread over many premium-payers. But in the context of an economic, rather than a financial, analysis the phrase 'at whose expense' has to be interpreted in a different way, based on the notion of opportunity cost, rather than on the notion of expenditure. When so reinterpreted, it means 'who is to go without' health care in order that other shall have it. Giving priority to one group of people means taking it away from another group, though for obvious reasons politicians tend not to dwell on this implication, leaving us to infer, from what is not said, who the 'low priority' groups are. In any honest and open discussion of these issues, however, that implication must be faced squarely, and we must not shrink from identifying who (implicitly) the 'low priority' people are, in any particular system of health care.

Health Planning↗
PubMed1988

The early diagnosis of legionnaires' disease in a Legionella pneumophila aerosol-infected guinea pig model; comparison of a method developed for detecting Legionella pneumophila antigens in urine and the demonstration of circulating antibody by enzyme-linked immunosorbent assay.

The appearance of Legionella pneumophila antigen in the urine of guinea-pig with experimental airborne legionnaires' disease was investigated and compared with that of emerging antibody by use of enzyme-linked immunosorbent assay. Models with high dose (acute) and low dose (chronic) infection were studied. Antigen was detected after 40 h in the high dose group but animals died (at 3 days) before an antibody response could be elicited. In the low dose group, antigen was detected 4 days after infection, well before serum antibody was detected (7-10 days). Small, but significant, amounts of antigen were detected up to 17 days after infection in surviving animals. Although detection of L. pneumophila antigen in urine has been proposed before, and achieved on an ad hoc basis, the technique is not in routine, general use. This is due mainly to difficulties of evaluation in relation to other methods of early diagnosis in the human situation where infectious dose, time of infection, host uniformity and availability of samples present difficulties. The use, in this study, of a highly relevant aerosol-infected guinea-pig model of legionnaires' disease has avoided these uncertainties and hopefully proved the value of this technique for general routine use. The antigen detection test was shown to be rapid, sensitive and reliable, and allowed diagnosis of legionnaires' disease earlier than was possible by demonstrating antibody. In addition, the detection of antigen in urine is a convenient and non-invasive procedure.

Aerosols↗