Biomedical subjects
G Tucker
Publications and source records attributed to G Tucker.
Novel bioconversions for the production of designer antioxidant and colourant flavonoids using polyphenol oxidases.
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Potent antioxidant properties of novel apple-derived flavonoids with commercial potential as food additives.
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Adam and Eve make love. Analysis of the enantiomers of 3,4-methylenedioxy-N-ethylamphetamine (MDE, "Eve") and its metabolite 3,4-methylenedioxyamphetamine (MDA) in rat brain.
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Language of dysfunction in schizophrenia.
Twenty-four medicated schizophrenic subjects participated in a study aimed at assessing language dysfunction in schizophrenia. Two groups of subjects participated: schizophrenic responders and non-responders to treatment with antipsychotic medication. All subjects were tested on The Western Aphasia Battery test (WAB), the Cookie Theft picture descriptions task, and the Wechsler Adult Intelligence Scales--Revised (WAIS-R) block design and picture arrangement subtests. All verbal and non-verbal assessments were compared between groups. The three main findings of this study were: 1. Severe language of dysfunction among schizophrenic patients who do not respond to medication treatment. That is, therapeutic response to medication was the major predictor of the severity of language dysfunction in schizophrenia. 2. A group profile of language dysfunction differed in severity but not in shape between responders and non-responders to treatment with antipsychotic medication. 3. Schizophrenic responders and non-responders to medication treatment did not differ in their performance on a standardised picture description task and failed to reach low-moderate aphasia level. Secondary findings suggest that non-verbal aspects, such as attention and logical sequencing, may be influenced by treatment. This study represents an assessment of schizophrenic language function in relation to known language deficits of neurological patients, lending further support for the role of central nervous system (CNS) dysfunction in schizophrenia, and the importance of assessing language dysfunction as a sensitive gauge to treatment response.
Cost-effective inpatient care of neuropsychiatric patients.
Managed care has decreased the frequency of hospitalization for psychiatric disorders, and it may have an especially strong impact on neuropsychiatric patients. The use of targeted, cost-effective interventions improves the quality of patient care and can assist with approval of funding for inpatient care by utilization review agencies.
Pathways to neuropsychiatry.
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Medical and narrative approaches in psychiatry.
Using a case example, the authors contrast two different approaches to psychiatric assessment: the medical approach, in which the physician examines signs and symptoms and compares them with diagnostic criteria for various disorders, and the narrative approach, in which the clinician tries to understand symptoms as a part of a meaningful story and as understandable responses to external conditions. Both approaches make essential contributions to psychiatry. The current conflict between biological psychiatry and psychotherapeutic psychiatry can be seen as a result of reductionist polarization involving these opposite approaches. The reconciliation of these opposites may be vital for the survival of general psychiatry as a medical specialty.
Rabies in a dog vaccinated by its owner.
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Management of the axilla in patients with breast cancers one centimeter or smaller.
Very small breast cancers are being diagnosed with increased frequency, and, until recently, little information regarding the incidence of axillary lymph node metastases in these most favorable tumors was available. Moreover, scarce data exist regarding axillary failure in this cohort as a function of initial treatment, be it surgery, radiation, or simply observation. In the present study, limited to women with invasive cancers measuring no more than 10 mm, the incidence of pathologically positive axillary nodes was 12.3%. The incidence of nodal metastases was influenced by tumor size (albeit not quite significantly, p = .08); not one patient with a tumor < or = 5 mm had axillary node metastases, compared to 14.7% in those with cancers 6 to 10 mm. The histologic grade and tumor location were also important in predicting nodal positivity. The incidence of positive nodes was 38% in those with poorly differentiated cancers, compared to 8% and 7% in women with well and moderately differentiated cancers, respectively, p = .03. Axillary nodal positivity was seen in 17% of outer quadrant vs 3% of central and inner quadrant primaries, p < .01. The axilla was managed with surgery alone (76%), radiation alone (6%), surgery and radiation (6%), or simply observation (10%). With a median follow-up of 55 months, not one patient has suffered a nodal recurrence, and in our experience, survival free of distant relapse was not adversely affected by the omission of axillary surgery.
Effects of low-dose TRH on cognitive deficits in the ECT postictal state.
A low dose (0.5 mg) of thyrotropin-releasing hormone (TRH), a short-acting tripeptide with known analeptic properties, was administered to eight depressed patients 5 minutes after ECT session 3 or 4 in a double-blind, placebo-controlled crossover design. After TRH infusion the patients displayed selectively better performance on a battery of neuropsychological tests than they did after placebo infusion. Further exploration with pharmacological probes to mitigate ECT postictal cognitive deficits is warranted.
Age as a prognostic factor for breast and regional nodal recurrence following breast conserving surgery and irradiation in stage I and II breast cancer.
PURPOSE: To evaluate the association between age and breast/regional nodal relapse following breast conserving surgery and irradiation. METHODS AND MATERIALS: The results of treatment in 511 patients with 519 Stage I and II breast cancers treated at Mallinkrodt Institute of Radiology and affiliated hospitals between 1958 and 1988 were reviewed. RESULTS: Seventy women, of whom 96% had axillary dissections, were 39 years of age or younger. These young patients were more likely to have chemotherapy (p < 0.0001), and tumor bed reexcision (p < 0.01), and less likely to have an undissected axilla (p < 0.01), or estrogen receptor positive tumor (p = 0.02) than the older women (> 40 years). Although breast recurrence tended to appear earlier in the younger patients (12% at 5 years for those < 40 years vs. 6% at 5 years for those older), by 7 years the breast failure rate for the two groups was the same (12%), p = 0.13. In the 37 women 35 years of age or younger, the actuarial rate of breast recurrence was 9% at 7 years. Compared to other series in the literature, in which cancers were grossly excised without regard to the microscopic margins of resection, and reexcision was not routinely performed, young women treated with breast conserving surgery and irradiation at our institution frequently underwent reexcision of the tumor bed (57%), and had negative pathologic margins of resection (75%). Regional nodal relapse was in general uncommon, and not seen with increased frequency in the youngest cohort. CONCLUSION: Our experience suggests that young age is not a contraindication to breast conserving surgery and irradiation. Although breast cancers in this cohort may have certain features rendering them prone to local failure, we believe this risk can be mitigated by appropriate patient selection and optimal surgical resection.
Regional nodal management and patterns of failure following conservative surgery and radiation therapy for stage I and II breast cancer.
PURPOSE: To determine the incidence, pattern of regional nodal failure, and treatment sequelae as determined by the extent of lymphatic irradiation. METHODS AND MATERIALS: The records of 511 patients with 519 Stage I and II breast cancers treated with breast conserving surgery with or without axillary dissection and irradiation were reviewed. The extent of nodal irradiation was at the discretion of the attending radiation oncologist and varied considerably over the years. Management of the axilla consisted of axillary dissection alone in 351, axillary dissection and supplemental irradiation in 74, irradiation alone in 75, and simply observation in 21 patients. RESULTS: Overall, axillary recurrence was uncommon (1.2%), but was slightly more frequent after irradiation alone (2.7%) than after surgery alone (0.3%), p = 0.14. There was no benefit for supplemental axillary irradiation after an axillary dissection yielding negative or 1 to 3 positive nodes. In the 21 patients in whom the axilla was observed, axillary recurrence was not observed. Supraclavicular failures were rare in women with negative or 1 to 3 positive axillary lymph nodes (0.5%), and not significantly affected by elective irradiation. Internal mammary node recurrence was seen in only one patient, and was not significantly influenced by elective internal mammary irradiation. Both arm and breast edema were significantly more common in women having breast and nodal irradiation than after breast irradiation alone. These sequelae were not influenced significantly by the number of lymph nodes obtained in the axillary dissection specimen. Radiation pneumonitis was seen with increased frequency with more extensive nodal radiotherapy. Pneumonitis was not found to be affected by the administration or sequencing of chemotherapy. CONCLUSION: There is little justification for axillary or supraclavicular irradiation following an axillary dissection which yields negative or minimally involved (1 to 3 positive) lymph nodes. There were too few patients with extensive axillary node metastases (> or = 4 positive) in our series to draw conclusions about the optimal extent of nodal irradiation in this subset. Elective internal mammary lymph node irradiation increases technical complexity, does not appear to be advantageous, and when combined with supraclavicular irradiation places the patient at highest risk for pneumonitis.
Drug delivery: lymphing along?
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Survival following breast-conserving surgery and irradiation or modified radical mastectomy in patients with invasive breast cancers with a maximum diameter of 1 cm.
The reported relapse-free survival for women with invasive breast cancers measuring no more than 10 mm in dimension ranges from 75% to 95%, with axillary status an important prognostic factor in most series. Further study of prognostic variables in this most favorable subset is notably limited. We retrospectively reviewed the records of 168 women with invasive breast cancers < or = 10 mm treated with either breast conserving surgery+axillary dissection (AXD) and radiation therapy, or mastectomy+AXD. The actuarial survival and survival free of distant metastases (DMFS) at 7 years was 95% and 97%, respectively. Location and size of the primary tumor were most important in predicting outcome, although statistical significance was not achieved. The 5-year distant metastases-free survival (DMFS) was 100% for central and inner quadrant tumors, compared to 97% in those with outer quadrant tumors, p = 0.18. The 5-year DMFS was 100%, 95%, and 98% for patients with cancers 2-5 mm, 6-9 mm, and 10 mm, respectively, p = 0.15. Status of the axillary lymph nodes, type of breast surgery, clinical tumor status (palpable vs. nonpalpable), age, menopausal status, histologic grade, systemic therapy, or histologic type were not found to have a significant impact on prognosis.
Now is the time to retire the term "organic mental disorders".
The organic/nonorganic distinction in contemporary classifications of mental disorders such as DSM-III and DSM-III-R has important prognostic and treatment implications, because it directs the clinician to pay special attention to the possibility of an underlying "physical" disorder as the cause of the mental disturbance. However, the term "organic" raises serious and intractable problems, since the connotative meaning of the term always returns to its historical roots, which imply an outmoded functional/structural, psychological/biological, and mind/body dualism. The authors present a proposal being considered for DSM-IV that would eliminate the term "organic" and reorganize the classification of organic mental disorders. Disorders previously referred to as "organic mental disorders" would be renamed as either "secondary disorders" (if they are due to "physical" disorders) or "substance-induced disorders." The entire classification of mental disorders would be reorganized to distribute the secondary and substance-induced disorders into the major groups with which they share phenomenology. The traditional organic mental disorders--delirium, dementia, and amnestic disorder--would be grouped together under the rubric of "cognitive impairment disorders." While acknowledging problems with the suggested new terminology and reorganization of the classification, the authors argue that the potential benefits of the proposal for clarity and for facilitating differential diagnosis justify putting to rest the familiar but now anachronistic term "organic mental disorders."
[In vitro conversion of carcinoma cells into fibroblastic cells. Induction, mechanism of action and importance in invasion and metastasis].
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Atypical mannolipids characterize Thy-1-negative lymphoma mutants.
Essentially all eukaryotic cells, including murine lymphomas, express surface proteins, such as Thy-1, which are anchored by a phosphoinositol mannolipid. Putative mannolipid anchor precursors can be detected in these cells. Six distinct Thy-1-negative lymphoma mutants lack complete mannolipids, and three mutants synthesize atypical mannolipids. The absence of complete mannolipids can account for the lack of expression of multiple mannolipid-anchored proteins and may also account for the lack of lipid anchoring in the human disease paroxysmal nocturnal hemoglobinuria. Structural information on the mannolipids of wild-type and mutant cells indicates that anchor biosynthesis in these cells may involve both transmembrane flip-flop of intermediates and a deacylation step.