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Biomedical subjects

K Jones

Publications and source records attributed to K Jones.

At least 469 records · Page 26Linked to original sources
PubMed1977

Oestrogen-associated disease of the renal microcirculation.

The effect of oestrogen-containing compounds on platelet factor 3, platelet life span, renal platelet localization and the fibrinolytic activity of forearm venous blood has been studied in eleven women with the renal vascular abnormalities of the loin pain and haematuria syndrome. The results were compared with those obtained in twenty-nine healthy female volunteer subjects. 2. Platelet factor 3 (PF3) availability was found to be increased in patients with the loin pain and haematuria syndrome during normal menstrual cycles. Oestrogens produced an increase in PF3 availability in both patients and control subjects. 3. Platelet life span was shortened and the index of renal platelet localization increased when patients with the loin pain and haematuria syndrome received oestrogens. No change in platelet kinetics was found in the healthy control subjects receiving oestrogens. 4. The fibrinolytic activity of forearm venous blood, both at rest and after venous occlusion, was increased in the healthy control subjects in response to oestrogens. No such response was seen in the patients with the loin pain and haematuria syndrome. 5. It is suggested that the change in platelet function may be causally related to the intrarenal vascular abnormalities. 6. The possible role of oestrogens in causing these disturbances or unmasking pre-existing abnormalities of platelet function or fibrinolysis is discussed.

Adult↗
PubMed1977

Chromosome variants in children with psychiatric disorders.

The authors studied the frequency of chromosome variants in 48 hospitalized children with psychiatric diagnoses (study group) in comparison with 10 hospitalized children with nonpsychiatric diagnoses (control group) and the results of three surveys of newborn children. They found that the frequency of variants in their study group was elevated in comparison with their control group and with the newborn surveys.

Adolescent↗
PubMed1976

Comparison of a gas chromatographic and colorimetric method for the determination of plasma paracetamol.

Plasma paracetamol levels have generally been determined either by gas chromatography (Stewart and Willis, 1975), which relies on complex equipment, or by spectrophotometry (Knepil, 1974), which can be time-consuming. The introduction by Glynn and Kendal (1975) of a simple colorimetric method based on the reaction of paracetamol with nitrous acid to give 2-nitro-4-acetamidophenol appears to have overcome these disadvantages, thereby providing a suitable procedure for the rapid measurement of plasma paracetamol in cases of overdose. The method was reported to be specific for paracetamol, no interference being caused either by the sulphate and glucuronide conjugates of paracetamol or by a large number of other commonly found drugs. This communication presents the results of a study in which plasma paracetamol levels determined by the colorimetric method were compared with those determined by an established gas chromatographic technique.

Acetaminophen↗
PubMed1976

A relative deficiency of cytochrome P-450 and aryl hydrocarbon [benzo(a)pyrene] hydroxylase in hyperplastic nodules induced by 2-acetylaminofluorene in rat liver.

The concentrations of cytochrome P-450 and the activities of aryl hydrocarbon [benzo(a)pyrene] hydroxylase (AHH) and reduced nicotinamide adenine dinucleotide phosphate-cytochrome c reductase were measured in early (gray-white) and remodeled (brown) hyperplastic nodules induced in the livers of rats with 2-acetylaminofluorene and were compared to the values in control livers and in the liver surrounding the nodules. Cytochrome P-450 content of early (14 weeks) hyperplastic nodules is 30% of the activity of untreated control livers and 48% of the activity of the surrounding liver. AHH activity of the early nodules is 10% of the control activity and 33% of the activity in the surrounding nonnodular liver. Nicotinamide adenine dinucleotide phosphate-cytochrome c reductase activity in the microsomes of early nodules is 76% of the control activity and 78% of the activity in the surrounding liver. In the late remodeled nodules, (22 and 25 weeks), the cytochrome P-450 content is 40% of that of controls and AHH activity is 15% of the control activity. In primary hepatomas induced by 2-acetylaminofluorene, cytochrome P-450 content is 21% of that of controls, AHH activity is 11% of the activity of controls, and reductase is 50% of the control activity. These results, indicating a relative nodule deficiency in some of the cellular components believed to be important in the activation of hepatocarcinogens and hepatotoxins, offer one possible explanation for the relative resistance to carcinogen cytotoxicity of hyperplastic liver nodules.

2-Acetylaminofluorene↗
PubMed1975

Oral contraceptives and breast cancer. Progress report of an epidemiological study.

322 women aged 16-45 years undergoing treatment for newly diagnosed breast cancer, together with 502 matched control patients, have been interviewed at six hospitals. The data suggest that the use of oral contraceptives is unrelated to the risk of breast cancer. While this result is reassuring, it is important to remember that it mst be many years yet before the question of the possible relation between oral contraceptives and breast cancer is finally settled.

Adolescent↗
PubMed1975

REM sleep and contingent negative variation development.

Three subjects demonstrated the ability to respond in a contingent negative variation (CNV) paradigm during rapid eye movement (REM) sleep. However, the CNV did not appear as it does in the waking state. This failure of the CNV to develop during REM sleep might be attributed to electrophysiological changes accompanying REM sleep.

Adult↗
PubMed1975

Skin porphyrin and photosensitivity in the porphyric rat.

Skin porphyrin assays and photobiological studies in normal and porphyric rats suggest that in the latter, skin photosensitivity to 400 nm radiation is associated with raised uroporphyrin and 7-carboxylic porphyrin in the skin.

Animals↗
PubMed1975

Sterilization: a review of 98 sterilized women.

The details of 98 women sterilized over a three-year period are presented. They show that female sterilization is a safe procedure which has a satisfactory result in many cases and confers many secondary benefits. However, some regret is common and is associated with a high incidence of psychiatric and marital morbidity, and this is shown to be related to pre-operative factors. A method of pre-operative assessment is outlined which should minimize the risk of a poor outcome following female sterilization.

Affective Symptoms↗
PubMed1974

In situ localization of globin messenger RNA formation. II. After treatment of Friend virus-transformed mouse cells with dimethyl sulfoxide.

Globin messenger RNA (mRNA) levels in Friend virus-transformed mouse cells have been estimated by in situ hybridization of DNA copy (cDNA) to fixed preparations of cells and by hybridization of cDNA to extracted cytoplasmic RNA in true solution. The results obtained by both methods agree in showing that a low level of globin mRNA can be detected in untreated Friend cells. The levels of hemoglobin and globin mRNA have also been correlated after treatment of Friend cells with dimethyl sulfoxide (DMSO). The results obtained by both experimental approaches show that there is a minimum period of treatment with DMSO required in order that Friend cells may become hemoglobinized, and that this period coincides with the time when globin mRNA accumulates. Moreover, bromodeoxyuridine prevents both hemoglobin and globin mRNA accumulation.

Animals↗