451
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Johnston M. Toward a culture of caring: children, their environment, and change. MCN. THE AMERICAN JOURNAL OF MATERNAL CHILD NURSING 1979; 4:210-4. [PMID: 109721] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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452
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Johnston M, Marcotte P, Donovan J, Walsh C. Mechanistic studies with vinylglycine and beta-haloaminobutyrates as substrates for cystathionine gamma-synthetase from Salmonella typhimurium. Biochemistry 1979; 18:1729-38. [PMID: 373802 DOI: 10.1021/bi00576a015] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Cystathionine gamma-synthetase (EC 4.2.99.9), a key enzyme in bacterial methionoine biosynthesis, has been found to use L-vinylglycine (2-amino-3-butenoate) and L-beta-haloaminobutyrates (X = F, Cl) as substrates in addition to the physiological gamma-substituted substrate O-succinyl-L-homoserine (OSHS). Vinylglycine is a substrate both for alpha-ketobutyrate formation (the normal product from gamma elimination with OSHS) and for cystathionine formation (the normal gamma-replacement product with OSHS) in the presence of cysteine. This behavior substantiates that the stabilized vinylglycine--pyridoxal phosphate (PLP) alpha carbanion is the key partitioning species in this enzyme's catalysis. The Vmax values for ketobutyrate production and cystathonine formation from vinylglycine are equivalent at approximately 45 U/mg, whereas the corresponding Vmax values from OSHS are 20 and 200 U/mg, respectively, suggesting different rate-determining steps with these two substrates. The beta-haloaminobutyrates undergo catalyzed HX elimination to yield bound aminocrotonate--PLP directly as a an initial intermediate and as a precursor of ketobutyrate. Little or no cystathionine formation is detectable when these substrates are incubated with enzyme and the normal cosubstrate cysteine, strongly indicating that the aminocrotonate--PLP intermediate is not in rapid, reversible equilibrium with the stabilized vinylglycine--PLP carbanion; in normal catalysis, the prototropic shift from alpha carbanion to aminocrotonate appears functionally unidirectional. The HX-elimination step from beta-chloroaminobutyrate is nonconcerted as demonstrated by a 3H2O in equilibrium chloroaminobutyrate exchange reaction. Further suggestion for discrete beta-halo-alpha-carbanionic intermediates derives from the observation that the haloaminobutyrates appear to a partition between ketobutyrate formation and enzyme inactivation. Since neither vinylglycine nor OSHS causes any detectable inactivation during turnover, it is likely that the inactivation species is not a common intermediate, i.e., the electrophilic aminocrotonate--PLP species (a potential Michael acceptor), but rather a species peculiar to the beta-haloaminobutyrate pathway. The beta-halo-alpha-carbanion--PLP intermediate has beta-halo-alpha-iminodihydropyridine character in the p-quinoid resonance contributor and is a good candidate for an alkylating agent by an SN2--displacement mechanism. Spectroscopic analyses of incubations with the various amino acid substrates show a number of long-wavelength absorbing species forming during turnover, tentative assignments are suggested.
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453
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Zipursky A, deSa D, Hsu E, Johnston M, Milner R. Clinical and laboratory diagnosis of hemostatic disorders in newborn infants. THE AMERICAN JOURNAL OF PEDIATRIC HEMATOLOGY/ONCOLOGY 1979; 1:217-26. [PMID: 543515 DOI: 10.1097/00043426-197923000-00005] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
We describe a microtechnology for the study of the coagulation system in newborn infants. Interpretation of results demands an understanding of the techniques used and the nature of the control population from which normal values are drawn. We have examined two syndromes which represent the majority of hemostatic disorders of sick newborn infants. The first is thrombocytopenia resulting from bacterial infections in which there are minimal changes in the levels of blood coagulation factors and little tendency to bleed. The second is a syndrome of disseminated intravascular coagulation in which there is a profound disturbance in the coagulation mechanism, relatively little change in platelet counts, a severe hemorrhagic diathesis, and widespread ischemic necrosis.
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454
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Johnston M. Children and parents in a changing world. THE AMERICAN NURSE 1978; 10:4-5. [PMID: 251420] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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455
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Johnston M. The work of a clinical psychologist in primary care. THE JOURNAL OF THE ROYAL COLLEGE OF GENERAL PRACTITIONERS 1978; 28:661-7. [PMID: 739467 PMCID: PMC2158955] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The data presented suggest that general practitioners would be likely to refer a large number of patients with diverse problems to clinical psychologists working in health centres. Compared with a centrally organized clinical psychology service, the work of the primary care psychologist is likely to offer the following advantages:1. Access to psychological help for patients with a need for such help, but who could not attend a central clinic owing to problems associated with travel, work, physical disability, or even a presenting problem such as agoraphobia.2. Greater continuity of care of patients.3. Increased communication between the psychologist and members of the primary care teams.4. Possibility of the psychologist seeing the patient earlier, before the problems have become entrenched.5. Less need for referral to other agencies.6. Reduced stigma for the patient.7. Development of new therapeutic approaches relevant to problems presenting in primary care.8. More flexible and more relevant therapy due to seeing the patients in their home setting.9. Greater therapeutic involvement of the patient's family.10. Reduced costs and inconvenience for the patient's family.11. Reduced administrative and ambulance service costs.While these points do not overcome the need for a formal evaluation of the work of psychologists in primary care, they do suggest that there are advantages in this type of service over the services which are currently available and that a full evaluation would be worth undertaking.
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456
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Johnston M, Kayne M, Mittleider K. Putting more PEP in parenting. Am J Nurs 1977; 77:994-5. [PMID: 586111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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457
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Finter NB, Fantes KH, Johnston M. Human lymphoblastoid cells as a source of interferon. DEVELOPMENTS IN BIOLOGICAL STANDARDIZATION 1977; 38:343-8. [PMID: 608522] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Interferons have considerable antitumour effects in animals, and have been used with encouraging results in patients with osteocarcomas and certain other tumours. So far only relatively small amounts of material suitable for use in man have been prepared, and almost all of this has come from human white blood cells [buffy coats]. Human fibroblast cell lines are now increasingly being used as an alternative source, but the resultant interferon differs in its chemical and biological properties from leucocyte interferon. Lymphoblastoid cells can also be induced to form an interferon which appears identical to buffy coat interferon. These cells can be grown in suspension in large tanks, and could provide large amounts of relatively inexpensive interferon. The advantages of this type of production system and the problems associated with it will be discussed.
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458
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Johnston M. Folk beliefs and ethnocultural behavior in pediatrics. Medicine or magic. Nurs Clin North Am 1977; 12:77-84. [PMID: 585016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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459
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Granberg J, Lowndes R, Robinson N, Busslinger M, Bunch D, Palmer J, Weitzel Y, Johnston M, Bowes W, Kenny M, Harvey J, Burden B. [Disseminated intravascular coagulation: a clinical study]. L' INFIRMIERE CANADIENNE 1976; 18:28-34. [PMID: 1087280] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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460
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Johnston M. Behavioural treatment of an eating problem. NURSING TIMES 1976; 72:1098-9. [PMID: 958934] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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461
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Johnston M. Responsiveness of delinquents and non-delinquents to social reinforcement. THE BRITISH JOURNAL OF SOCIAL AND CLINICAL PSYCHOLOGY 1976; 15:41-9. [PMID: 1260239 DOI: 10.1111/j.2044-8260.1976.tb00005.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
A series of six experiments, involving 198 subjects, examined the hypothesis that delinquents are less responsive than non-delinquents to social reinforcement and punishment. The hypothesis received support (a) using two different experimental techniques, one in which the subjects' judgements of autokinetic movement were modified and one using the Taffel (1955) verbal conditioning paradigm; (b) with the female adult administering the reinforcement and with a peer; (c) when the contingent social cues were rewarding (Good or Fine) and when they were punishing ('No'). The hypothesis was not supported when the verbal reinforcement was varied. Control studies using no reinforcement and money reinforcement indicated that the social reinforcement did indeed have a specific reinforcement effect and that delinquents did not show a general learning deficiency.
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462
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D’Aoust J, Aris B, Thisdele P, Durante A, Brisson N, Dragon D, Lachapelle G, Johnston M, Laidley R. Salmonella eastbourne outbreak associated with chocolate. ACTA ACUST UNITED AC 1975. [DOI: 10.1016/s0315-5463(75)73804-x] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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463
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Evans LE, Hunter P, Hall R, Johnston M, Roy VM. A double-blind trial of intravenous thyrotrophin-releasing hormone in the treatment of reactive depression. Br J Psychiatry 1975; 127:227-30. [PMID: 810198 DOI: 10.1192/bjp.127.3.227] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
In a double-blind trial 600 mug. of thyrotrophin-releasing hormone (TRH) was compared with placebo given daily for four days to two groups of ten patients. There was no significant difference between the antidepressant effects of TRH and placebo.
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464
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Greenbaum LM, Grebow P, Johnston M, Prakash A, Semente G. Pepstatin, an inhibitor of leukokinin formation and ascitic fluid accumulation. Cancer Res 1975; 35:706-10. [PMID: 46779] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Ascites fluid accumulation accompanying a mastocytoma or L1210 murine tumor is significantly retarded following the i.p. or s.c. injection of moderate quantities of pepstatin, a known acid protease inhibitor. No effect on cell count was noted by pepstatin treatment. The probable mechanism by which pepstatin acts is by inhigiting the enzymatic formation of chemical mediators known as leukokinins. These are pharmoacologically active peptiedes having potent permeability characteristics previously described by this laboratory. Leukokinins are formed by cathepsin D-like enzymes present in the invading cells and in the ascites fluid acting on a protein substrate, leukokininogen. present in the ascites fluid. Pestatin inhibits the action of these leukokinin-forming enzymes invitro but has no effect on kallikreins (bradykinin-forming enzymes) in vitro. Human ascites fluid from a patient with ovarian carcioma was found to have a paepstatin-inhibited, leukokinin-generating system, as does the mouse. A 'chemical mediator' theory is proposed for ascites fromation which broadens the previously held theory of lymphatic blockage (Holm-Nielsen) and may explain the recent findings of Hirabayashi and Graham of increased plasma-ascites exchange in peritoneal carcionmatosis. Pepstatin inhibition of chemical mediator formation may represent a new therapeutic approach to ascites fluid accumulation in neoplastic disease.
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465
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Morgan FD, Hopkins D, Morgan BJ, Johnston M, Ford RM. Letter: The housedust mite in Adelaide South Australia. Med J Aust 1974; 2:224-5. [PMID: 4420095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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466
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Gomez RF, Johnston M, Sinskey AJ. Activation of nitrosomorpholine and nitrosopyrrolidine to bacterial mutagens. Mutat Res 1974; 24:5-7. [PMID: 4602225 DOI: 10.1016/0027-5107(74)90040-2] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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467
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Greenbaum LM, Prakash A, Semente G, Johnston M. The leukokinin system; its role in fluid accumulation in malignancy and inflammation. AGENTS AND ACTIONS 1973; 3:332-4. [PMID: 4131798 DOI: 10.1007/bf01986490] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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468
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Bennett AE, Johnston M, Williams R, Perry J. Population-based studies in the evaluation of a community hospital. BRITISH JOURNAL OF PREVENTIVE & SOCIAL MEDICINE 1973; 27:71-2. [PMID: 4717825 PMCID: PMC478773 DOI: 10.1136/jech.27.1.71-b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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469
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Winkley JH, Weibel L, Davies WD, Johnston M. Topical treatment of burns. Surg Clin North Am 1968; 48:1365-73. [PMID: 4972534] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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470
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471
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Johnston M. In-service lectures at Crease Unit. THE CANADIAN JOURNAL OF PSYCHIATRIC NURSING 1968; 9:4. [PMID: 5183915] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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472
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Johnston M, Kahlson G. Experiments on the inhibition of histamine formation in the rat. BRITISH JOURNAL OF PHARMACOLOGY AND CHEMOTHERAPY 1967; 30:274-82. [PMID: 6036410 PMCID: PMC1557251 DOI: 10.1111/j.1476-5381.1967.tb02134.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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473
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Wolf M, Risley T, Johnston M, Harris F, Allen E. Application of operant conditioning procedures to the behavior problems of an autistic child: a follow-up and extension. Behav Res Ther 1967; 5:103-11. [PMID: 6025711 DOI: 10.1016/0005-7967(67)90004-6] [Citation(s) in RCA: 112] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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474
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Johnston M. Kidney transplantation. THE JOURNAL OF THE KANSAS MEDICAL SOCIETY 1967; 68:228-36. [PMID: 5342653] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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475
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Johnston M. Histamine formation in rats bearing the Walker mammary carcinosarcoma. EXPERIENTIA 1967; 23:152-4. [PMID: 6032118 DOI: 10.1007/bf02135977] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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