Predictive value of mutagenicity tests in chemical carcinogenesis.
Explore the source record for details and available documents.
SEARCH · PubMed Health
Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
Explore the source record for details and available documents.
Since peripheral vascular disease (PVD) is the forerunner of coronary heart disease (CHD), it is vital to detect PVD at an early stage. In the past, the non-invasive ankle arm index (AAI) has been successfully used to predict the susceptibility of PVD/CHD. However, different authors have used different permutations (i.e. highest, average and lowest) of ankle (ASBP) and arm (HSBP) systolic blood pressures to calculate AAI. This study aims to investigate the validity and applicability of different permutations of AAI formulae to predict sub-clinical PVD/CHD in young individuals. The study also investigated whether the use of AAI post-moderate exercise would enhance the predictability of PVD or CHD at an early stage. Individuals from different ethnic background within the UK took part in this study. Following 5min moderate cycle exercise using 50% of heart reserve, the AAI was significantly reduced (P<0.05). It was found that not all the permutations of AAI were acceptable and some over/under estimated AAI compared to currently accepted methodologies. According to the statistical analysis (ANOVA and 95% limits of agreement) calculation of AAI using values of (1) highest ASBP divided by highest HSBP, (2) highest ASBP divided by average HSBP, (3) average ASBP divided by highest HSBP and (4) lowest ASBP divided by average HSBP were within acceptable agreement with the standard method of calculating AAI. Inclusion of these permutations together with the standard method, would give a better predictions of PVD/CHD at an early age.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Balloon test occlusion (BTO) of the internal carotid artery (ICA) is used in conjunction with single-photon emission computed tomography (SPECT) imaging to assess the cerebrovascular collateral reserve prior to surgical manipulation of the artery. The present report reviews 56 consecutive patients with tumors or vascular lesions at the base of the skull who underwent BTO and subsequent treatment on that basis within a 3-year period. Four patients underwent carotid sacrifice, since they tolerated the BTO and had normal SPECT imaging. Postoperatively, one patient had patchy infarcts in the frontal lobe, another a middle cerebral artery territory infarction, a third had a lacunar infarct, and the fourth had an impending stroke and was treated with an emergent revascularization procedure. There were 15 patients who underwent saphenous vein bypass grafting, of these there were three graft occlusions, one of which resulted in an infarction. There were two other infarctions due to technical difficulties, one being related to the revascularization procedure. Based on these results, we suggest that passing BTO with a normal SPECT study does not necessarily indicate that the patient is immune to stroke following carotid sacrifice. Revascularization should be considered, when ICA sacrifice is deemed necessary to treat the pathologic condition adequately, to minimize the likelihood of a stroke.
One hundred and six adults with various reactions to yellow jacket (YJ), honey bee (HB) or unidentified insects (UI) were tested for allergy to insect venoms. For various reasons none received immunotherapy. Individuals completed questionnaires annually for three consecutive years and described sting reactions within the previous season. Ninety subjects completed all the questionnaires and 77 of these were re-tested at the end of the period. Nine out of 25 patients reacted with a systemic reaction when re-stung. High IgE and low IgG venom-specific antibody levels indicated an unfavourable prognosis, since eight of 11 individuals who initially presented venom-specific IgE greater than RAST class 2 and venom-specific IgG below detection limit had systemic reactions at re-sting. No such reactions occurred in subjects with no specific IgE and only one out of six with specific IgE as well as IgG reacted systematically. Skin prick tests (SPT) of less than 3mm with YJ venom 1,000 micrograms/ml excluded later systemic symptoms to stings, whereas larger skin reactions gave an equal chance of systemic or local reactions at re-sting. In individuals not stung by UI, YJ and/or HB the decline in venom-specific IgG and IgE was significant, median values ranging from 41% to 75% over the 3-year period. The decline was unaffected by the type of sting reaction prior to the initial test. SPT results did not change significantly. The findings are relevant when testing patients several years after their last insect sting and the results might indicate that the antibody decline is accompanied by a decrease in clinical sensitivity.
Explore the source record for details and available documents.
OBJECTIVE: To investigate the impact of predictive genetic testing on colonoscopic surveillance in an extended family with hereditary non-polyposis colorectal cancer (HNPCC). SETTING: Familial Bowel Cancer Service, The Royal Melbourne Hospital, Victoria. SUBJECTS: 96 people registered with the Service who were apparently unaffected members of an extended family that met the classic Amsterdam criteria for HNPCC and carried an MLH1 gene mutation (IVS9 + 3insT). INTERVENTION: Predictive genetic testing was offered in a cascade manner to at-risk family members; mutation-positive individuals were advised to have annual colonoscopic surveillance, while mutation-negative individuals were withdrawn from surveillance. MAIN OUTCOME MEASURES: Previous compliance with recommended colonoscopic surveillance; uptake and results of genetic testing; expected effect of genetic test results on number of colonoscopies over five years. RESULTS: 22 of the 96 family members (23%) were not complying with recommended surveillance. Of 48 individuals offered predictive genetic testing, 41 (85%) responded and 39 (81%) underwent testing. Seven of the 39 (18%) were positive for the family-specific mutation, and 32 (82%) were negative. The 39 tested individuals and 37 of their descendants who were registered with the screening program had undergone 70 colonoscopies in the five years before genetic testing. In the five years after testing, only 37 surveillance colonoscopies were planned (annual or two-yearly colonoscopies for the six mutation-positive individuals and five-yearly colonoscopies for four mutation-negative individuals with previously identified adenoma), an almost 50% reduction in colonoscopies. CONCLUSION: Predictive genetic testing in HNPCC families allows many individuals to be withdrawn from regular colonoscopic surveillance. It may therefore reduce costs, as well as have emotional benefits for many individuals.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
The EEG, as recorded from electrodes in deep structures of the brain in cases of intractable seizures, has been surveyed to assess its predictive value in the partial epilepsies. In addition to scalp EEGs and depth EEGs in control situations, ictal recordings of tape-recorded seizures and the interictal enhancement of EEG signs by benzodiazepines have been analyzed. All results have been quantified by computer analysis. The predictive value of the EEGs has been assessed in 2 ways: (1) by comparison with the pathology found after surgery and (2) by the long-term clinical status of the patient postoperatively. Twelve cases with lesions found in limbic structures and 6 with cortical involvement are reported. In the latter cases secondary firing of the hippocampus, with its low threshold for seizures, frequently followed, though more rapidly than could be timed by visual inspection alone. Bilateral signs both in scalp EEGs and in depth were a common finding in the cases with limbic lesions. In those patients with marked clinical improvement, follow-up computerized studies of pre- and post-operative scalp EEGs revealed normalization in both hemispheres, leading to the proposal that a focus of defective tissue may impair neuronal function in widely distant regions of the brain.
The laboratory tests of 38 patients in pediatric age with Disseminated Intravascular Coagulation (DIC) were retrospectively evaluated. In all patients were performed PT, aPTT, platelets count, FDP dosage and biological assay of Fibrinogen. In most of them the activity of FII, FV, FVII, FX and FVIII was assaied. According to the diagnostic criteria of FSP greater than 8 micrograms/ml, Platelets less than 150 10(9)/1 and Fibrinogen less than 150 ml/dl, in 16 patients the diagnosis of DIC was possible since first examination, while in 9 patients it became possible within 2-4 days; in 13 patients we never could diagnose DIC, although it was reasonably present, since the criteria above mentioned were never simultaneously satisfied. Looking back in our experience, we confirm that the platelets count and the quantitation of plasmatic Fibrin Degradation Products (FDP) are the most useful tests for the diagnosis of full blown DIC, and that the biological assay of plasmatic fibrinogen helps to follow the disorder. A low level of FVIII:C seems to be a forecast of failure. None of the other test performed give any useful information for diagnosis when it is not possible with the above mentioned tests.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
In a prospective study the accuracy of B-mode ultrasound imaging alone was compared with its use in conjunction with bidirectional Doppler ultrasound, carotid phonoangiography, and oculoplethysmography to independently assess contrast arteriograms of carotid arteries studied for presumed extracranial vascular disease. The addition of B-mode real-time imaging improved the accuracy of diagnosis by nearly 10%.