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Biomedical subjects

D J Anderson

Publications and source records attributed to D J Anderson.

At least 379 records · Page 21Linked to original sources
PubMed1985

Affinity chromatographic examination of a retention model for macromolecules.

Plots of log k' vs. log (1/[mobile phase modifier]) were made for a monovalent and a divalent solute using affinity chromatography. Some of the plots were curved and all exhibited slopes (Z values) of less than the theoretical integer values. It was shown that this was an expected result when lower forms of the solute were present, e.g., a divalent solute adsorbed monovalently.

Chromatography, Affinity↗
PubMed1985

A study of the NB/7OK and CA 125 monoclonal antibody radioimmunoassays for measuring serum antigen levels in ovarian cancer patients.

Serum levels of tumor antigens NB/7OK and CA 125 were determined in 101 samples by radioimmunoassays with the use of murine monoclonal antibodies. Among serum samples from ovarian cancer patients, elevated NB/7OK levels were found in 87% of samples that contained elevated CA 125 levels. With either assay, only 2% of patients with nonmalignant diseases had elevated antigen levels. No quantitative correlation was found, however, between levels of NB/7OK and CA 125. When antigen present in serum was purified by gel filtration on Sephacryl S-200, CA 125 eluted with an apparent molecular weight in excess of 100 kilodaltons whereas NB/7OK eluted with an apparent molecular weight of 70 kilodaltons. Thus the NB/7OK and CA 125 radioimmunoassays appear to measure two different populations of antigenic material.

Antibodies, Monoclonal↗
PubMed1985

Localization of transferrin receptor in the chorionic villi of complete molar pregnancy.

Transferrin receptors have been identified on the villous trophoblast of normal chorionic villi by immunohistochemical techniques. The current study investigated the expression of transferrin receptors on molar chorionic villi by using a monoclonal antibody in immunofluorescence assays. The villous trophoblast of molar chorionic villi was brightly positive for transferrin receptor in the immunofluorescence assay. The presence of transferrin receptors on molar villous trophoblast may influence the immunologic relationship between molar and host tissues.

Antibodies, Monoclonal↗
PubMed1985

Environmental and genetic factors that influence immunity and longevity in mice.

Many different theoretical approaches may be taken toward understanding the association between aging and immunologic malfunction. The leading theory is based on the natural phenomenon of thymic involution and argues that the T-dependent lymphoid system is genetically programmed to decline in effectiveness, possibly through altered endocrine and central nervous system controls. The "thymic time clock" theory of aging is strongly supported by the consistent finding of defective cellular immunity functions in aged humans and animals and an associated development of the age-related diseases. In several animal models, including autoimmune-prone strains, high spontaneous tumor incidence strains, and normal long-lived strains, it has been possible to forestall the development of the major diseases of aging and extend longevity by restricting diet. The predominant effect of dietary restriction is prolongation of immunologic vigor and retardation of the immunologic dysfunction that normally occurs with age. Studies on environmental factors affecting longevity such as these and others which demonstrate a complex interaction between genes influencing longevity underscore the complexity and challenge of aging research.

Aging↗
PubMed1985

Feasibility, reliability, and advantage of utilizing low contrast dose digital subtraction ventriculography in a conventional catheterization laboratory.

Ventriculography was performed with conventional biplane fluoroscopic equipment; a 1:4 dilution of contrast medium in a standard injectate volume was delivered by a power injector. The biplane images were acquired with two video tape recorders and enhanced by means of a portable digital image processor. By a simple modification and calibration of our standard light pen-computer system, volumes could be calculated and global and segmental wall motion analysis performed. Fifteen patients underwent conventional and low-dose left ventriculography. Good correlation was found in end-diastolic volume (EDV), in end-systolic volume (ESV), and in ejection fraction (EF) (r = 0.90, r = 0.93, and r = 0.92, respectively). The quality of the images enabled a frame-by-frame analysis of a cardiac cycle to be performed (r = 0.99 when compared in one patient) and regional wall motion abnormalities identified (21 out of 23 abnormal segments). Although conventional ventriculography caused a rise in left ventricular end-diastolic pressure (17 +/- 8 vs 23 +/- 11, p less than 0.002) and no change in systolic blood pressure (132 +/- 23 vs 135 +/- 23, p greater than 0.5), low-dose ventriculography had no effect on left ventricular end-diastolic pressure (18 +/- 7 vs 21 +/- 10, p greater than 0.05) and produced a rise in systolic blood pressure (144 +/- 20 vs 149 +/- 22, p less than 0.05). A system of digital enhancement that is capable of producing high-quality ventriculograms with lessened contrast morbidity can be assembled with minimal expense and adapted to any conventional catheterization laboratory.

Cardiac Catheterization↗
PubMed1985

Reactivity of anti-human sperm monoclonal antibodies with normal placenta, hydatidiform mole, and gestational choriocarcinoma.

The current study was undertaken to examine reactivity patterns of well-characterized anti-human sperm monoclonal antibodies with normal placenta, complete hydatidiform mole (HM), and gestational choriocarcinoma (CCA). Two anti-human sperm monoclonal antibodies (MA2 and MA7) out of a panel of 14 reacted with human CCA cell lines but did not react with the trophoblast of 4 HM or 4 normal placentas from 13 weeks to term gestation in immunofluorescence and absorption tests. Therefore, in terms of expressing these sperm-embryonic antigens, the trophoblast of HM is more like normal placental trophoblast than CCA. The relationships among normal placenta, HM, and CCA may be better understood by continued studies on the pattern of expression of additional embryonic antigens in these three gestational tissues.

Antibodies, Monoclonal↗
PubMed1985

Localization of stage-specific embryonic antigens in hydatidiform mole, normal placenta, and gestational choriocarcinoma.

Murine stage-specific embryonic antigens (SSEA-1, SSEA-3) are well characterized oncofetal antigens and have been identified in several human tumors. The current study was undertaken to determine the localization of SSEA-1 and SSEA-3 in hydatidiform mole, normal human placenta, and gestational choriocarcinoma. SSEA-3 did not react with any cellular components in hydatidiform moles, normal placentas, or choriocarcinoma cell lines. SSEA-1 was detectable in two human gestational choriocarcinoma cell lines, but not in the trophoblastic cells of 10 hydatidiform moles or in nine normal placentas between 6 weeks and term gestation. Therefore, according to this oncofetal marker system, the trophoblast in hydatidiform mole is more like normal trophoblast than gestational choriocarcinoma.

Antigens, Neoplasm↗
PubMed1985

Molecular probes for the development and plasticity of neural crest derivatives.

We have isolated cDNA clones for several mRNAs expressed in sympathetic neurons but not in adrenal chromaffin cells, two neural crest derivatives thought to share a common precursor. The tissue specificity, developmental expression, and hormonal regulation of these genes have been characterized using Northern blot and in situ hybridization analysis. We find that these mRNAs are independently regulated in development rather than synchronously induced. Our evidence also implicates Nerve Growth Factor (NGF) in the induction of one of these genes in postmigratory crest cells. Two of these genes become induced in mature chromaffin cells, which express a neuronal morphology in response to NGF. These results support the idea that the phenotypic plasticity of neural crest derivatives reflects a common precursor, the multipotentiality of which is sustained through terminal differentiation.

Adrenal Medulla↗
PubMed1985

The possible relation between mastication and parotid secretion in the rabbit.

Salivary flow has been recorded from conscious rabbits during 1 min periods whilst continuously chewing standard laboratory dry pellets or pieces of carrot and, in some animals, a mash of pellets with water. Flow was measured using contact drop recorders or a continuous flow recorder via Polythene tubes permanently inserted into one or both parotid ducts. Large variations in flow were obtained with unilateral recordings particularly during dry pellet chewing. Bilateral recordings showed that the flow was always greater on one side than on the other and that dominant secretion alternated from side to side in an apparently random manner. Rabbits chew unilaterally. Videotaped recordings of chewing movements showed that the greater secretion was always produced on the chewing side. To test the possibility that drying of the oral mucosa, or the prolonged hardness of the pellets may result in higher flow rates in animals with cannulated ducts than would normally be seen in intact animals, water was injected downstream into the mouth through a third cannula. This was inserted in an anterograde direction in the parotid duct on one side. Significant reductions in flow were recorded during dry pellet eating, but not during carrot eating. When animals were fed a soft pellet mash, salivary flow was significantly lower than with dry pellets. Recordings have been made from strain gauges attached to the ascending ramus of the mandible. Previous findings that dry pellets produce greater strain than carrots have been confirmed. It has also been shown that less strain is produced with soft pellet mash. The strain gauge data suggested that a relation exists between masticatory force and parotid salivary flow. The results are compatible with the hypothesis that intra-oral mechanoreceptors may be involved in a masticatory-salivary reflex.

Animals↗
PubMed1985

Gamma-interferon enhances expression of Class I MHC antigens in the weakly HLA+ human choriocarcinoma cell line BeWo, but does not induce MHC expression in the HLA- choriocarcinoma cell line Jar.

PHA-activated lymphocyte supernatants and high doses of affinity-purified human gamma-interferon enhance the expression of apparently normal Class I histocompatibility antigens in a malignant human trophoblast cell line that expresses low amounts of these antigens under normal culture conditions. Another human choriocarcinoma cell line, Jar, which is normally HLA-, did not respond to this treatment. This system provides a model in which to study further the regulation and effects of MHC antigen expression in cells of trophoblastic origin.

Antibodies, Monoclonal↗
PubMed1984

Vestibulospinal reflexes as a function of microgravity.

The idea that sustained microgravity will result in altered otolith input requiring a modification of postural control was explored by using the pathway that links the otolith organs and spinal motoneurons. Two related methods were used. First, the Hoffmann reflex was used to measure at specific times the excitability of the soleus-spinal motoneuron pool during a brief unexpected linear acceleration. Second, extensive dynamic postural testing with a moving platform was done before and after flight. The Hoffmann reflex amplitude, reflecting otolith-modulated motoneuron sensitivity, was low in flight after adaptation, and its postflight potentiation may have been dependent on rate of adaptation. The strength of inflight motion sickness symptoms was related to postflight Hoffmann reflex amplitude. Dynamic posture tests showed significant deviations from the results obtained before flight. The strategy used for balance on the moving platform was modified, and the behavior of the subjects suggested a decrease in awareness of the direction and magnitude of the motion.

Electromyography↗
PubMed1984

Diazepam and propranolol in panic disorder and agoraphobia.

The response to diazepam and propranolol hydrochloride was compared in 21 patients who (with one exception) met DSM-III criteria for panic disorder and agoraphobia. Each drug was administered for two weeks in double-blind fashion according to a crossover design. The response to diazepam was significantly superior on all measures. By observer rating, 18 patients showed at least moderate improvement with diazepam compared with seven receiving propranolol. Panic attacks and phobic symptoms responded to diazepam, but not to propranolol. The results suggest that benzodiazepines constitute effective short-term treatment for these newly defined disorders.

Adult↗