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T Mason

Publications and source records attributed to T Mason.

At least 91 records · Page 5Linked to original sources
PubMed1983

Heme regulates transcription of the CYC1 gene of S. cerevisiae via an upstream activation site.

We show that expression of the iso-1-cytochrome c gene of Saccharomyces cerevisiae, CYC1, is tightly regulated by levels of intracellular heme. Expression is reduced at least 200-fold in cells grown under conditions of heme deficiency. Studies on the regulation of a CYC1-lacZ fused gene and direct determination of mRNA levels indicate that this control is transcriptional. Furthermore, we show that the heme regulatory site in the CYC1 promoter region is an upstream activation site (UASc) centered about 275 bp upstream from the region of transcriptional initiation. The latter region is required for optimal transcription and contains three TATA box sequences and six prominent mRNA initiation sites that span 34 bp. Substitution of the UASc with the UAS of the yeast GAL10 gene results in activation of the normal set of CYC1 transcripts. In this case, however, transcription is independent of regulation by heme, suggesting that in the wildtype, heme controls initiation per se and not translation or mRNA stability.

Cytochrome c Group↗
PubMed1982

Determination of left ventricular ejection fraction by visual estimation during real-time two-dimensional echocardiography.

It has been shown that the measured reduction in the cross-sectional area of the left ventricle (LV), as viewed in the short axis, closely approximates its ejection fraction (EF). We assessed the reliability of using two-dimensional echocardiography (2DE) to visually estimate the EF during real-time viewing, without the need of digitizers, planimetry, or calculations. Twenty-five adult hospitalized patients with either suspected or known cardiac disease were evaluated prospectively. Each patient also had gated nuclear angiography during the same admission, and 14 had cardiac catheterization with left ventriculography. The EF was determined by 2DE using a visual estimate of the percent area reduction of the LV cavity in the short-axis view at the level of the papillary muscles. All 2 DE studies were read by two or more blinded reviewers, with a value for the EF to the nearest 2.5% determined by consensus. These values correlated closely to the values determined in all 25 patients with gated nuclear angiography (r = 0.927) and the 14 patients who had left ventriculography (r = 0.935). We believe that this method of visually estimating the LVEF will enable echocardiographers to easily use 2 DE for a reliable and instantaneous assessment of ventricular function, without the need of sophisticated analytical equipment.

Adult↗
PubMed1980

Simultaneous transurethral prostatectomy and herniorrhaphy. A study of 63 cases.

Transurethral prostatectomy and herniorrhaphy were performed as a combined procedure for 63 patients during the period 1974 to 1978. The intraoperative and postoperative courses are compared with those of a control group of 82 patients who underwent herniorrhapies as an isolated procedure during the same period. The simultaneous performance of transurethral prostatectomy and herniorrhaphy in this group of patients was safe as well as cost-effective.

Acute Disease↗
PubMed1977

Oestrogen excretion and ovarian pathology in postmenopausal women with atypical hyperplasia, adenocarcinoma and mixed adenosquamous carcinoma of the endometrium.

Urinary oestrogen and pregnanediol excretion were measured before and after hysterectomy and bilateral salpingo-oophorectomy in 26 postmenopausal women with adenocarcinoma of the endometrium, 10 postmenopausal women with mixed adenosquamous carcinoma and 11 postmenopausal women with atypical hyperplasia (the patient groups). The results were compared with the values obtained in 22 active postmenopausal women, 20 hospitalized postmenopausal women and 18 women who had been subjected to hysterectomy and bilateral salpingo-oophorectomy for cancer of the cervix (the control groups). The ovaries and Fallopian tubes obtained at operation were examined for evidence of current or past excessive oestrogen production. Preoperative oestrogen values were higher in the patient groups than in the controls and the elevated values persisted after oophorectomy. The implications of these findings are discussed.

Adenocarcinoma↗
PubMed1976

Systematic variables affecting simian virus 40-induced T-antigen expression and transformation in human cells.

Simian virus 40 (SV40) infection of human skin fibroblast and human tumor cells resulted in the expression of T-antigen and transformed foci. By examining various conditions of input virus multiplicity and initial cell density, the systematic variation of T-antigen determination was minimized. The most uniform results were obtained at multiplicities of about 275 plaque-forming units/cell. Within limits (5 X 10(4) to 2 X 10(5) cells/dish), initial cell density had little effect on T-antigen expression. Volume of virus inoculum was critical for some cell lines, but not for others. Cell passage level had no general effect on T-antigen expression, although specific cell lines demonstrated increased or decreased levels of T-antigen expression with serial passage for no apparent reason. T-antigen expression correlated with virus-induced cell transformation (focus formation) at two different multiplicities. In addition, T-antigen assays at 3 days gave consistently more reproducible results than transformation assays at 21 days in seven cell lines tested at two multiplicities of infection. These results defined input multiplicity as the major source of systematic variability and will permit development of a more reproducible tool in the evaluation of individuals at high risk of cancer.

Antigens, Neoplasm↗
PubMedDate not supplied

Tarasoff liability: its impact for working with patients who threaten others.

Few court rulings can have had the international impact on mental health professionals than the case of Tarasoff in the U.S.A. For psychiatric nurses the issues pertaining to this case affects the everyday working practices for those working with patients who, at one stage or another, threaten the welfare of others. This is as much the case for forensic psychiatric nurses as it is for general psychiatric nurses, and indeed any nurse who receives a threat, regarding a third party, from a patient. This paper sets out the brief history of the Tarasoff case and highlights the main issues for practitioners. Tarasoff and the problem of social control is discussed and the professional concerns regarding the prediction of violence and the duty to third parties are debated. The ramifications of the Tarasoff case, in terms of its restrictions and extensions, are outlined, and the impact for carers is discussed.

Duty to Warn↗
PubMedDate not supplied

Developmental effects of intermittent prenatal exposure to 1,1,1-trichloroethane in the rat.

The effects of daily three 1-h exposures to 7000 ppm 1,1,1-trichloroethane (TCE) on physical and behavioral development were examined in Sprague-Dawley rats exposed during the last week of gestation. A sham group was exposed to filtered air. Offspring of both groups were fostered to untreated dams. No significant group differences were detected in total maternal weight gain or food and water consumption, but differences were observed in initial litter characteristics, including a longer gestation period in the TCE group, a smaller number of litters delivered in the TCE group, and fewer live pups per litter in the TCE group. At birth, the total litter weight was less in the TCE group, but there was no significant difference in average pup weight. Pups prenatally exposed to TCE did not differ from shams in day of eye opening, pinnae detachment, or incisor eruption. The TCE group weighed less the first 2 weeks of life, was impaired in its ability to perform the inverted screen, negative geotaxis, and vertical screen tests, and had less forelimb grip strength. Locomotor activity was reduced in the TCE group, and the ratio of brain to body weight was reduced in TCE-exposed offspring. These data provide evidence for neurobehavioral teratogenicity of intermittent prenatal exposure to high concentrations of TCE in rats.

Animals↗
PubMedDate not supplied

Aerobic capacity, weight gain and psychotropic medication.

The relationship between physical health and psychological wellbeing is a complex one, with each impacting upon the other to one degree or another. Psychiatric patients are often reported to be not as physically healthy as their counterparts in the general population, with reports of increased weight gain and decreased activity. This study of two classifications of psychiatric patients in a high security psychiatric establishment was an attempt to ascertain if such a relationship existed between physical fitness, psychopathology, weight gain and medication levels. Using standardized tests to assess two parameters of health-related fitness--Harpenden skinfold callipers to estimate percentage body fat (BF), and a submaximal cycle ergometer ride for aerobic capacity (VO2 max)--results were compared with the general population using the Allied Dunbar National Fitness Survey (Sports Council and Health Education Authority, 1992) as a reference. The results indicate significant differences in aerobic fitness between the two groups (P < 0.01) and such differences could be a cause for concern and may constitute a threat to both physiological and mental wellbeing.

Adult↗