Search PubMed⌕ Search

Biomedical subjects

A Hart

Publications and source records attributed to A Hart.

At least 91 records · Page 5Linked to original sources

Mastectomy or conservation: the patient's choice.

STUDY OBJECTIVE: To determine whether, if given the choice, patients with breast cancer would prefer mastectomy or conservation treatment, neither treatment having been shown to be preferable. DESIGN: Non-randomised case series with 28 patients interviewed after two years and all followed up. SETTING: Secondary care referral centre. PATIENTS: 153 women, aged less than 65, with T1, T2, N1, and N0 tumours of the breast given the choice of treatment (that is, all eligible patients from December 1979). INTERVENTIONS: Patients were asked, after information and counselling, which treatment they would prefer. The chosen treatment was given without further question. Mastectomy included node sampling and local radiotherapy if indicated. Conservation treatment comprised excision of the lump, external radiotherapy, and irridium wire implant to tumour bed. MAIN RESULTS: Conservation treatment was chosen by 54 women and mastectomy by 99. Reasons for preferring mastectomy included desire for rapid treatment for domestic or employment reasons and fear of possibility of future mastectomy. Only two of the sample interviewed regretted their choice. During limited follow up no advantages to either form of treatment were seen in terms of recurrence or survival. CONCLUSIONS: Patients with breast cancer are capable of choosing treatment and should play a part in deciding which treatment to have. They do not automatically choose to retain the breast.

Adult↗

Buoyant density fluctuations during the cell cycle of Bacillus subtilis.

A simple rapid method for preparing synchronous cultures of Bacillus subtilis has been used to investigate changes in density during the cell cycle. Asynchronous cells separated on a stepped Percoll density gradient had a mean cell density of 1.117 g ml-1 +/- 0.004. Samples from a synchronous culture exhibited variation (ca. 1.5%) in mean cell density which was greatest at the onset of cell division. An asynchronous control culture showed little variation in density. These results are discussed in relation to previous work on Escherichia coli.

Bacillus subtilis↗

Nondetectable levels of interferon gamma is a critical host defense during the first day of herpes simplex virus infection.

Previous studies have demonstrated the importance of IFN alpha/beta in resistance to primary viral infections. However, the role of IFN gamma in primary infections is unclear. The present studies were undertaken to determine whether IFN gamma induction was an important early host defense against primary HSV infection. The approach was to block the IFN gamma response with antibodies to IFN gamma prior to infection and at various times post-infection (p.i.). The data indicates that treatment of mice with anti-IFN gamma prior to infection enhanced mortality (89% vs 37%). Anti-IFNs given at various times post HSV challenge proved most effective within the first 24 h of infection. The above results suggest for the first time that IFN gamma mediates important host defense(s) early during primary HSV infection. Similar results were obtained using antibody to IFN alpha/beta.

Animals↗

Prognostic implication of hyperdiploidy as based on DNA flow cytometric measurement in childhood acute lymphocytic leukemia--a multicenter study.

The pretreatment distribution of DNA content was determined in the leukemic blasts of 114 children with standard risk acute lymphocytic leukemia. The patients were admitted to four different centers for pediatric oncology, participating in a national study ALL-V. In 39 of 107 evaluable patients (36.4%), a single aneuploid leukemic line was detected with a median DNA Index of 1.22 (range 1.10-1.40). These hyperdiploid patients did not differ from those with diploid disease for the presenting features of age, sex, FAB classification, immunophenotype, or white blood cell count. However, patients with hyperdiploid acute lymphocytic leukemia had a significantly longer (p = 0.021) disease-free survival after a median observation period of 52 months. These observations indicate that routinely applied flow cytometry of DNA content can identify a fairly large subgroup of children with standard risk acute lymphocytic leukemia who have a low probability of relapse. It may be considered to exempt these patients from more intensive treatment regimens.

Aneuploidy↗

Ultrastructural features of Cowdria ruminantium in midgut epithelial cells and salivary glands of nymphal Amblyomma hebraeum.

Colonies of Cowdria ruminantium were studied in midgut epithelial cells and salivary gland acini of nymphal Amblyomma hebraeum that were infected experimentally as larvae. Colonies were found in both tissues and studied with light and electron microscopy. Colonies observed within gut cells frequently contained 2 types of the organism: electron-dense and reticulated forms. The morphology of colonies from salivary glands, as seen with light microscopy, varied from compact, densely-staining, small colonies to larger ones in which individual organisms were apparent. With electron microscopy, most organisms in salivary glands were reticulated and appeared to be dividing by binary fission. In both types of host cells, colonies often contained a dense inclusion to which reticulated organisms were adhered.

Animals↗

Ultrastructural and biochemical changes in human jejunal mucosa associated with enteropathogenic Escherichia coli (0111) infection.

A case of prolonged diarrhoea following Escherichia coli 0111 gastroenteritis is reported. Electron microscopy of the jejunal biopsy revealed effacement of the brush border and attachment of bacteria by pedestal formation. Specific activities of brush border enzymes showed marked depression of disaccharidases, zinc-resistant alpha-glucosidase, and alkaline phosphatase. In contrast, marker enzymes for basolateral membranes and endoplasmic reticulum were unaffected. The biochemical changes support the pathogenic mechanism suggested by ultrastructural studies previously reported.

Biopsy↗

Hormonal regulation of four urea cycle enzymes in postnatal rat liver in organ culture.

The administration of hydrocortisone to 3- to 15-day-old rats increased the levels of hepatic argininosuccinate synthetase (ASS) and arginase. In 13-day-old rat liver explants maintained in organ culture, ornithine carbamoyltransferase (OTC), carbamoylphosphate synthetase (CPS) and arginase were stimulated by betamethasone. Actinomycin D prevented the responses of the latter two enzymes. Dibutyryl cyclic AMP raised OTC, CPS, ASS and arginase in vitro. The responses of the latter three enzymes were blocked by cycloheximide and puromycin and partially inhibited by actinomycin D. The simultaneous presence of betamethasone and dibutyryl cyclic AMP in the culture medium raised CPS and OTC in an additive manner. The sequential treatment of the cultures with betamethasone followed by dibutyryl cyclic AMP increased CPS and arginase synergistically and amplified the response of ASS to dibutyryl cyclic AMP.

Animals↗

The treatment of advanced bladder cancer with methotrexate and cis-platinum--a pharmacokinetic study.

As part of a phase III study in advanced bladder cancer, 5 patients received methotrexate (MTX) 50 mg/m2 as a single agent every 2 weeks, and with every alternate dose of MTX (i.e. every 4 weeks) cis-platinum (CDDP) 50 mg/m2 was given simultaneously, together with saline hydration and diuresis. The clearance of MTX was measured in a total of 12 courses by serial serum sampling for up to 72 hr following injection. In 4 patients (with a mean pretreatment creatinine clearance of 97 ml/min) there was no significant difference between the clearance of MTX when given alone [mean t1/2 (beta) 3.2 hr] and when given 2 weeks later with concurrent CDDP [mean t1/2 (beta) 2.9 hr]. In 1 patient with a pretreatment creatinine clearance of 52 ml/min the clearance of MTX when given alone (without hydration) was significantly delayed compared with the clearance of MTX when given 2 weeks later concurrently with CDDP and saline hydration [t1/2 (beta) 19 and 4.5 hr respectively]. Of the 5 patients so far treated with MTX-CDDP, 2 have had a partial objective response and 3 have had stable disease (including 2 with a marked subjective response). These data indicate that in patients with satisfactory renal function, low-dose MTX and CDDP may be given concurrently without risk of enhanced drug toxicity.

Aged↗

An organ culture of postnatal rat liver slices.

A technique for the organ culture of postnatal and adult rat liver has been developed. Liver slices, 0.3 mm thick, were maintained in Conway units at the interphase between medium and a 95% O2:5% CO2 atmosphere. Postnatal liver in culture for up to 72 h had healthy hepatocytes throughout the explants; if adult liver was used the upper 0.2 mm was healthy after 24 h. These slices incorporated tritiated orotate and leucine into trichloroacetic acid-precipitable material. Incorporation of orotate was shown to be spread over the entire slice of neonatal liver. Culturing did not alter the potassium ion content of postnatal liver. Tyrosine aminotransferase activity in liver slices from postnatal, adult, and adrenalectomized adult rats was stimulated by glucocorticoids and dibutyryl cyclic AMP. Cycloheximide and actinomycin D prevented this response. Further, cortisol exerted a permissive effect on the stimulation of tyrosine aminotransferase activity by dibutyryl cyclic AMP in slices from adrenalectomized rats. Induction of urea cycle enzymes by cortisol was demonstrated in cultures of liver from adrenalectomized adult animals.

Adrenal Glands↗

Plasma fibrinogen levels and the clinical course of acute myocardial infarction.

Plasma fibrinogen levels were followed from admission to the coronary care unit up to 3 months after an acute myocardial infarction (AMI) (51 patients at entry--49 patients at follow-up). Mean initial value as determined with 24 hours of onset of symptoms was 522 mg% +/- 205 S.D. Peak value 845 mg% +/- 215 S.D. was reached 3-5 days after onset of symptoms. Mean fibrinogen level on a later follow-up was similar to the initial value (521 mg% +/- 145 S.D.). Our data confirm that a rise in the plasma fibrinogen level is common after myocardial necrosis. No correlation was found between the maximum peak value and the clinical course of the disease. However, death, reinfarction and cardiogenic shock were more frequent among patients with an initial plasma fibrinogen level higher than 400 mg%. Our findings suggest that the acute increase in fibrinogen following necrosis is less significant to the clinical course than a chronically high plasma fibrinogen level.

Adult↗