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Biomedical subjects

W G Jones

Publications and source records attributed to W G Jones.

At least 109 records · Page 6Linked to original sources
PubMed1983

Endotoxins in cotton: washing effects and size distribution.

Endotoxin contamination was measured in washed and unwashed cottons from three distinct growing areas, California, Mississippi, and Texas. The data show differences in endotoxin contamination based upon the geographic source of the cotton. It is also shown that washing bulk cotton before the carding process results in lower endotoxin in the cotton dust. Washing conditions can affect the endotoxin levels, and all size fractions of the airborne dust contain quantifiable endotoxin contamination. Endotoxin analyses provide a simple and reliable method for monitoring the cleanliness of cotton or airborne cotton dusts.

Air Microbiology↗
PubMed1983

The quantitation of sister chromatid exchanges in lymphocytes of cancer patients at intervals after cytotoxic chemotherapy.

Venous blood was taken from patients with cancer, prior to and up to 42 days after the administration of cytotoxic chemotherapy. Lymphocytes were stimulated to divide in vitro, and examined for sister chromatid exchanges (SCEs). Cyclophosphamide rapidly increased the frequency of SCE, which returned to approximately double the control value 24 hr after administration. The remaining SCEs disappeared more slowly. There was a positive correlation between the dose of drug and the frequency of SCE measured immediately and 4 hr, 20 hr and 21 days after treatment. As patients received successive courses of treatment the number of SCEs generally increased from about 0.14 to 0.25 per chromosome. After this, further chemotherapy was often less effective in inducing them. The presence of SCEs in peripheral blood lymphocytes may be a useful indicator for the occurrence and persistence of alkylating metabolites, residual damage in the DNA and individual responses of patients to a standard regimen.

Adult↗
PubMed1983

An EORTC phase II study of vindesine in advanced prostate cancer.

In a phase II study of vindesine in patients with bi-dimensionally measurable primary or metastatic prostate cancer, 27 patients (given 3 mg/m2 weekly for at least 4 treatment cycles) were evaluable for response 6 weeks from the start of treatment. Dose escalation to 4 mg/m2 weekly was attempted. Five patients (19%) achieved a partial remission of short duration, 11 patients (41%) showed no change and 11 patients (41%) showed progression. Thirty-one patients were evaluable for toxicity. Neurotoxicity occurred in 58% (severe in 23%) and was apparently cumulative dose-dependent, although there was variable individual sensitivity. Haematological toxicity was evidenced by lack of dose escalation in 32% of patients, dose delay in 71% and some degree of anaemia in 48%. Alopecia occurred in 55%. Other toxicities were few and minor. Vindesine shows marginal activity in prostatic cancer but at this dose schedule causes appreciable toxicity.

Aged↗
PubMed1983

Radiation treatment planning for bladder cancer: a comparison of cystogram localisation with computed tomography.

A comparison has been made between the target volumes of radical radiotherapy treatment plans produced with the aid of marker cystograms, and target volumes derived from computed tomography (CT) scans in 60 patients with bladder cancer. This has demonstrated inadequacies of the cystograms due to the inability to delineate extravesical spread of tumour and, as many patients with bladder cancer had a significant residual urine, emptying the bladder by catheterisation may have given a false impression of the shape and size of the target volume. Analysis of the results showed that cystographic localisation resulted in serious underdosage of the tumour in 18% of patients and failure to include all the bladder in 37%. Conventionally produced target volumes showed potentially significant discrepancies in 85% of patients when compared with target volumes delineated by CT.

Humans↗
PubMed1983

Respiratory effects of diesel exhaust in salt miners.

The respiratory health of 259 white males working at 5 salt (NaCl) mines was assessed by questionnaire, chest radiographs, and air and He-O2 spirometry. Response variables were symptoms, pneumoconiosis, and spirometry. Predictor variables included age, height, smoking, mine, and tenure in diesel-exposed jobs. The purpose was to assess the association of response measures of respiratory health with exposure to diesel exhaust. There were only 2 cases of Grade 1 pneumoconiosis, so no further analysis was done. Comparisons within the study population showed a statistically significant dose-related association of phlegm and diesel exposure. There was a nonsignificant trend for cough and dyspnea, and no association with spirometry. Age- and smoking-adjusted rates of cough, phlegm, and dyspnea were 145, 159, and 93% of an external comparison population. Percent predicted flow rates showed statistically significant reductions, but the reductions were small and there were no dose-response relations. Percent predicted FEV1 and FVC were about 96% of predicted.

Adult↗
PubMed1982

Serum ferritin as a third marker in germ cell tumours.

Serial measurements of serum ferritin have been assessed as an additional marker in a study of 12 patients with germ cell tumours. The standard markers, serum AFP and beta HCG, were also assessed serially. During treatment elevated levels of serum ferritin were detected in 10 patients, elevated AFP in 10 patients and elevated beta HCG in 6 patients. A poor prognosis was associated with persistently raised serum ferritin and either, or both, elevated AFP and beta HCG levels. Decreasing levels of serum ferritin indicated favourable response to treatment; rising values were associated with recurrence or dissemination of tumour. Even if serum ferritin cannot be classed specifically as a tumour product, it may be useful in the early detection of residual or recurrent tumour.

Adolescent↗
PubMed1982

Sister chromatid exchanges in human lymphocytes exposed to single cytotoxic drugs in vivo or in vitro.

Venous blood was taken from apparently healthy volunteers and patients with cancer, the latter both before and at intervals after treatment with single cytotoxic drugs. Cells from untreated individuals were exposed to a range of concentrations of drugs in culture medium. Chlorambucil, treosulfan and cyclophosphamide (activated by hepatic microsomes) significantly increased the numbers of SCEs, both in vitro and in the lymphocytes of patients. While methotrexate and 5-fluorouracil had no effect, bleomycin slightly increased the number of SCEs, but only in vitro. Although the in vitro dose-effect relationship indicated which drugs would increase the frequency of SCE in vivo, the magnitude of the response tended to be overestimated. When patients were treated with drugs the frequency of SCE increased, then declined with time. Though this complicates the quantitative relationship between dose and damage, SCEs may be useful to monitor the effects of alkylating agents on normal tissues.

Adult↗
PubMed1980

Lymphocyte supernatants and the electrophoretic mobility of erythrocytes: further experience of cancer diagnosis.

A double-blind trial of the tanned-erythrocyte electrophoretic mobility test for cancer has been carried out. This included 70 normal subjects as controls, 61 subjects with disease other than cancer, and 229 cancer patients. Slowing values generally increased in the order given, with certain diseases having values within the range positive for cancer. Exposure to viral infection also tended to produce false positives. Slowing values above 50%, however, appear to be definitely associated with cancer. For the middle range of slowing values (25-50%) there is some overlap between the 3 groups, so that a statistical probability of the presence of malignancy is available from the test. With slowing values below 25% there is little likelhood of cancer. Tumour type influences the test result, as does, to a lesser extent, tumour bulk.

Adult↗
PubMed1978

A whole blood control for the Coulter Model S.

The white cell count, red cell count, haemoglobin, and mean cell volume of a new preserved whole blood preparations used as a control material for the Coulter Model S were found to be stable for at least two months. This material provides a cheap and stable whole blood control which is now in routine use in 18 laboratories throughout Wales.

Blood↗
PubMed1977

Further observations of the detrusor electromyogram.

Using sophisticated recording equipment and two fine copper wire electrodes introduced through the cystoscope into the bladder muscle of conscious patients at cystoscopy, reproducible electromyographic recordings were obtained from the normal and the neuropathic bladders of a group of patients. By means of simultaneous recording of the electromyographic activity of the rectus abdominis muscle in these patients, it was found that, in general, the variations in electromyographic activity of the normal bladder with filling and voiding are quite independent of abdominal muscle activity. The upper motor neuron bladders by a way of contrast showed continuing electrical activity even at rest and this activity increases with abdominal contraction. Lower motor neuron bladders remain electrically silent at all times including during abdominal muscle contraction. This suggests that the bladder electrodes do not record muscle activity from the abdomen or elsewhere and confirms the validity of the detrusor EMG.

Abdominal Muscles↗