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Biomedical subjects

A Martin

Publications and source records attributed to A Martin.

At least 739 records · Page 41Linked to original sources
PubMed1984

Genetic analysis of transdetermination in Drosophila. I. The effects of varying growth parameters using a temperature-sensitive mutation.

The heat-sensitive mutation of Drosophila melanogaster l(3)c4(3)hs1, causes mutant larvae raised at a restrictive temperature to have abnormally large wing discs. The large size of these discs is a disc-autonomous property and results from an increase in the number rather than the size of wing disc cells. We have used wing discs from this mutant to further investigate properties of transdetermination which had previously been investigated with nonmutant discs. Transdetermination can occur in nonmutant discs when the proliferative phase of imaginal disc development is extended by wounding discs and culturing them in vivo. The results indicate that additional proliferation in the absence of wounding does not lead to transdetermination. There is a correlation between the extent of growth of a cultured disc and the probability that it will undergo transdetermination. The results suggest that this correlation does not depend on a differential rate of cell division. Finally, the results indicate that the cells which give rise to transdetermination are at an equivalent developmental stage no later than that characteristic of eye-antenna disc cells before the third larval instar.

Animals↗
PubMed1984

[Surgery and circulating antiprothrombinase-type anticoagulant in the Soulier-Boffa syndrome].

A case is reported of a young female patient with a circulating lupus anticoagulant. The illness, associated with several spontaneous abortions, is characterized as a "Soulier and Boffa syndrome". No severe bleeding occurred when she underwent several major operations. The clinical picture of lupus anticoagulant is discussed, as well as the perioperative management of such patients. The presence of a lupus anticoagulant, if not associated with other hemostatic defects, is not a contraindication to surgery. The risks and benefits of postoperative heparinization are recalled. Thrombin time seems to be the best coagulation test for adapting heparin doses.

Abortion, Habitual↗
PubMed1984

Five-year follow-up of 101 elderly subjects by means of long-term ambulatory cardiac monitoring.

Long-term follow-up of 101 healthy elderly subjects living independently in the community has been undertaken by means of clinical examination, resting ECG and 24-hour ambulatory cardiac monitoring. It appears that the finding of ventricular premature complexes at the rate of 10 per hour or greater is associated with a significant increase in mortality. The prevalence of atrial fibrillation, initially found to be 11%, rises with age to 17% by the age of 84 years. Long-term ambulatory monitoring is essential in the proper documentation of paroxysmal atrial fibrillation. Bundle branch block also occurs in over 10% of elderly people and the prevalence rises steeply with age, so that at the end of this study more than one quarter of the survivors had evidence of His-Purkinje disease. Over 5% of our subjects had definite indications for pacing during the period of follow-up and lends support to the opinion that the current pacemaker implantation rate in the United Kingdom is below the optimal level.

Aged↗
PubMed1984

Five-year cure of cervical cancer treated using californium-252 neutron brachytherapy.

Female pelvic carcinoma is one of the common malignancies seen at the University of Kentucky Medical Center and often presents in an advanced stage. In 1976, we began to test californium-252 neutron brachytherapy (NT) for its efficacy for control of primary and recurrent advanced uterine, cervix, and vaginal cancers. The first protocol used was 5000-5500 rad of whole pelvis irradiation followed by 1-2 Cf-252 insertions using a single tandem placed in the utero-cervico-vaginal region. Of 27 patients with primary carcinomas treated, 10 are alive and well 5 years later (37%). Two of two recurrent tumors were locally controlled but failed later. These patients had advanced cervical, vaginal, or endometrial carcinomas. In 1977, a transitional year, treatment of only unfavorable stages and presentations with NT was initiated. Similar results were obtained with NT as compared to conventional photon therapy (PT). Further improvement in treatment results can be anticipated as NT brachytherapy is used for advanced cancer therapy by more effective treatment schedules and radiation doses. Cf-252 can be used as a radium substitute and achieved similar rates of tumor control and 5-year survivals.

Adenocarcinoma↗
PubMed1984

Glycosyltransferase activities in the rat intestinal mucosa: comparison between standard commercial and semi-synthetic diets.

Two groups of rats were fed either a commercial (C group) or a semi-synthetic (S group) diet of very similar quantitative composition, which induce similar growth in the animals. Glycosyltransferase activities are very different in the two groups: fucosyltransferase is lower in S group than in C group, regardless of the expression of the results (specific activity versus protein or DNA). The other activities (galactosyl-, N-acetylglucosaminyl-, N-acetylgalactosaminyltransferases) are modified when expressed versus DNA content; N-acetylneuraminyltransferase specific activity is not altered. Since the weight of mucosa is significantly lower in the S group than in the C group, all the total activities are decreased in the S group. The fucosylation process is further characterized by partial purification of the enzyme and study of the synthesis of GDP-fucose. In each case, interfering reactions (glycosyl-nucleotide pyrophosphatases and proteinases) are controlled. The results give evidence that glycosyltransferases are very sensitive to the qualitative composition of the diet.

Animals↗
PubMed1984

An anti-mouse macrophage monoclonal antibody reacting with T-derived leukaemic cells.

Hybridomas secreting anti-mouse macrophage antibodies were obtained by fusing a murine plasmacytoma with lymphocytes of a rat immunized against mouse macrophages. An IgM, monoclonal antibody (3 A 35) reacted with mouse monocytes, macrophages and polymorphonuclear leucocytes. It did not bind appreciably to erythrocytes, platelets and unstimulated T or B lymphocytes. However, 3 A 35 bound to various murine T-derived leukaemic cells and to a small proportion of Con A-stimulated thymocytes. Cross absorption experiments confirmed the existence of a common antigenic determinant on macrophages and leukaemic cells. The possibility that 3 A 35 identified a previously described antigen common to macrophages and normal or leukaemic T cells was investigated. The antibody was tested against thymocytes and macrophages of various mouse strains, some congenic for H-2 or T1a. The 3 A 35-detected antigen was found to be different from Ly5, Tla and Qa and did not represent a I-J encoded allotypic specificity.

Animals↗
PubMed1984

Phase I study of immunotherapy by live Brucella abortus (strain 19 BA) in cancer patients.

Twenty-eight patients showing negative responses against Brucella antigens were included in a preliminary trial of immunotherapy by a live Brucella abortus vaccine. Seventeen patients had squamous cell lung carcinoma, eight had acute myeloid leukemia, and three were classified as "others." Brucella abortus strain 19 BA was administered sc in a single injection at doses ranging from 5 X 10(7) viable organisms to 10(10), ie, 40 times the usual vaccine dose. No important toxicity was noted. Edematous reactions at the injection site and febrile responses were infrequent and moderate, hemocultures were all negative, spleen volume did not vary significantly, and cbc showed an increase of polymorphonuclear cells and lymphocytes.

Blood Cell Count↗
PubMed1983

Malignant mesothelioma. The Eastern Cooperative Oncology Group (ECOG) experience.

The Eastern Cooperative Oncology Group has conducted a retrospective review of their experience of 96 patients with a tissue diagnosis of malignant mesothelioma treated between 1972 and 1980 on four separate sarcoma chemotherapy protocols. Thirty-two of the 96 patients were diagnosed and treated in South Africa. There were 75 males and 21 females with an age range of 27 to 78 with a median of 58.1 years. All, except for 28 patients, had some form of prior therapy. The median time from the onset of symptoms to diagnosis was 12 weeks; from the diagnosis to randomization was 15.1 weeks. Only 12 of the 96 patients demonstrated an objective regression. The responses were 7/51 on Adriamycin with 2 complete responses (complete responses--38 weeks and 52 weeks), 2/24 on Adriamycin combinations, 2/7 on cycloleucine, 1/3 on bleomycin, and 0/10 on non-Adriamycin combinations. Only 1/28 responded to a cross-over therapy (Adriamycin). The median survival from the start of protocol chemotherapy was 7.4 months and 7.5 months for Adriamycin treated patients. The median survival for responders was 29.9 months, compared to 6.3 months for nonresponders. The median survival for this entire series from the time of first symptoms was 15.2 months. The median survival for the 7 patients with abdominal mesothelioma was 12 weeks. There was a slight improvement in survival for the South Africans as compared to the Americans. Malignant mesothelioma in this series, was a rapidly lethal, nonresponsive disease whose treatment will require new therapies.

Abdominal Neoplasms↗
PubMed1983

Enzymatic screening of human uterine cervical biopsies in nonpregnant and pregnant women at parturition.

Twelve enzymatic activities, involved in the metabolism of proteins, collagen, glycosaminoglycans, or in the energy metabolism, were studied in 72 cervical biopsies obtained after delivery of the placenta and in 12 cervices obtained by hysterectomy in nonpregnant patients. Although these activities display high interindividual variations, they are greatly and significantly increased at parturition as compared to the nonpregnant state, with the exception of creatine kinase, which is maximum in cervices obtained from nulliparous nonpregnant women. The activities are low in the group of women who are 35 to 40 years old. The other studied factors (blood group, parity, pregnancy duration, labor length, treatment, state of the cervix at the 9-month examination) have no clear influence on the enzymatic levels. The results are discussed in relation to the well-known structural changes of the cervix at parturition.

Adult↗
PubMed1983

Improved detection of Duchenne muscular dystrophy heterozygotes using discriminant analysis of creatine kinase levels.

We have assessed the sensitivity and specificity of tests to detect carriers of Duchenne muscular dystrophy by use of three serum enzymes (creatine kinase, pyruvate kinase, and aldolase) and discriminant analysis in 21 obligate heterozygotes and 28 normal controls. We found no significant age effects on enzyme levels. Each enzyme level considered separately was significantly higher in heterozygotes. Use of logs improved discrimination, and log CK was sufficient by itself as a discriminant (that is, addition of other enzymes did not significantly improve discrimination). We present procedures to generate posteriori probabilities for genetic counselling that incorporate prior probabilities and enzyme levels. Our results show both improved sensitivity (90%) and specificity (86%).

Adult↗
PubMed1983

Characterization and sorting of mouse cytotoxic macrophages by their light scattering properties.

The light scattering properties of mouse activated macrophages were analyzed by flow cytometry. Peritoneal adherent cells from B. abortus treated animals were found to segregate into two subpopulations as a function of their forward angle and 90 degrees angle light scatter. The cell subpopulations were separated by automatic sorting. The strongly scattering ones contained an elevated proportion of large volume and acid phosphatase rich cells. Their nonspecific cytotoxic activity against tumor cells was more important than that of weakly light scattering cells. Thus, flow cytometry might be helpful to characterize and isolate cytotoxic macrophage populations.

Animals↗
PubMed1983

Extended Hildebrand solubility approach: p-hydroxybenzoic acid in mixtures of dioxane and water.

The extended Hildebrand solubility approach was used to reproduce the solubilities of p-hydroxybenzoic acid in a dioxane-water system. The solubility parameter of p-hydroxybenzoic acid was determined and found to be approximately 15 (cal/cm3)1/2. Residual plots (scattergrams) were used in conjunction with R2, F, and standard deviation values to determine whether a quadratic, cubic, quartic, or higher degree polynomial was required in the calculations. The earlier iteration method for back-calculations of solubilities was replaced by the more reliable root-finder method. The solubility profile of p-hydroxybenzoic acid in dioxane-water mixtures did not follow a log linear relationship even in the ranges where the solubility parameters of the water-cosolvent mixture might be expected to produce a straight-line function, as observed in other studies.

Chemical Phenomena↗
PubMed1983

The suppression of ethanol self injection by buprenorphine.

The schedule induced self-injection procedure was used to establish ethanol self-injection in 16 rats. Pretreatment with an injection of 0.3 mg/kg buprenorphine significantly reduced ethanol self-injection in a group of 8 rats. This effect was not found in a second group of 8 rats which received saline pretreatment. The findings provide support for an involvement of buprenorphine, in ethanol self-injection, which cannot be explained in terms of opiate induced shifts in taste preference. From the present data it cannot be determined whether the agonist or antagonist opiate properties of buprenorphine cause the blocking effect.

Alcohol Drinking↗
PubMed1983

Word production and comprehension in Alzheimer's disease: the breakdown of semantic knowledge.

Relatively mildly impaired patients with suspected Alzheimer's disease (N = 14; Verbal IQ = 96) and normal controls of similar age and education (N = 11) were administered tests requiring production (naming and fluency) and comprehension of single words. Word comprehension was assessed on a superordinate level (rating words for degree of "pleasantness") and on a more specific level (matching abstract pictorial representations with printed words denoting objects, action, emotions, and modifiers). Performance on standardized measures of semantic knowledge (Vocabulary and Similarities subtests of the WAIS) was also evaluated. The naming and fluency abilities of the Alzheimer's patients were found to be highly correlated (r = .80) and impaired. Naming errors often consisted of semantic field errors which were either hierarchically or linearly related to the target name. In comparison with normals, verbal fluency was characterized by a tendency to generate proportionally more category names concurrent with reduced production of items within a category. Single-word comprehension was also impaired, except when judgments of affective meaning were required. It was argued that these results suggest that Alzheimer's disease may lead to a specific disruption in semantic knowledge characterized by a difficulty in differentiating between items within the same semantic category concurrent with the relative preservation of broader categorical information.

Aged↗
PubMed1983

Differentiation of cytotoxic adherent cells from peroxidase positive cells after intraperitoneal injection of Brucella abortus organisms.

The relations between the cytotoxic adherent cells (CAC) and the peroxidase positive adherent cells (PPAC) which appeared after i.p. injection of Brucella abortus were investigated. A kinetic study showed that PPAC preceeded CAC. Twenty-four hours after bacterial injection, almost all adherent cells stained for peroxidase and no cytotoxic activity could be recorded. Cells sampled at this moment acquired cytotoxic properties by cultivation in LPS containing medium. The treatment of the bacterial organisms by HCl or chloroform: methanol (C:M) suppressed their ability of inducing CAC but not that of inducing LPS-activatable PPAC. The substances extracted by C:M could activate PPAC into CAC in vitro. The data presented suggest that CAC differentiate from PPAC, that the recruitment of PPAC is not always followed by their transformation into CAC and that different components of the bacterial organisms might be necessary to achieve the steps of cell recruitment and maturation.

Animals↗
PubMed1983

Studies on the fate of labelled palmitic acid in rat lung.

1. Pulmonary palmitic acid metabolism was studied in rats in basal conditions and after experimental talcosis. 2. Palmitic acid was rapidly incorporated into phospholipids and stored in the form of esterified cholesterol. 3. During the experiment a de novo synthesis of triglycerides was not detected.

Animals↗