PubMed Health⌕ Search

Biomedical subjects

H J Day

Publications and source records attributed to H J Day.

At least 19 recordsLinked to original sources
PubMed1992

Amyloidosis. Part II. Implications for neuroscience nurses: Alzheimer's disease.

UNLABELLED: Amyloidosis describes a group of diseases characterized by deposition of abnormal fibrous proteins in body organs and soft tissues. This disease complex is classified under the broad headings primary and secondary based on whether or not chronic infections or inflammatory conditions coexist. In addition, localized versus systemic involvement and heredofamilial considerations are used to subclassify amyloidosis. Many primary and secondary amyloid diseases involve the central, peripheral and autonomic nervous systems. This paper will focus on the latest information concerning systemic and localized forms of amyloidosis involving the nervous system with special emphasis on Alzheimer's disease and amyloidosis secondary to spinal cord injury. The roles of the nurse related to diagnosis, patient care, patient and family education and identification of support systems in the community will be covered. Patient care will be discussed from the standpoint of process and outcome criteria for specific nursing diagnoses. OBJECTIVES: 1. Describe the pathophysiological processes of amyloidosis. 2. Relate four aspects of nursing care to nursing diagnoses. 3. List four critical elements to include in patient/family education.

Alzheimer Disease↗
PubMed1991

Amyloidosis. Part I. Implications for neuroscience nurses: introduction and amyloidosis secondary to spinal cord injury.

Amyloidosis describes a group of diseases characterized by deposition of abnormal fibrous proteins in body organs and soft tissues. This disease complex is classified under the broad headings primary and secondary based on whether or not chronic infections or inflammatory conditions co-exist. In addition, localized versus systemic involvement and heredofamilial considerations are used to subclassify amyloidosis. Many primary and secondary amyloid diseases involved the central, peripheral and autonomic nervous systems. This paper will focus on the latest information concerning systemic and localized forms of amyloidosis involving the nervous system with special emphasis on Alzheimer's disease and amyloidosis secondary to spinal cord injury. The roles of the nurse related to diagnosis, patient care, patient and family education and identification of support systems in the community will be covered. Patient care will be discussed from the standpoint of process and outcome criteria for specific nursing diagnoses.

Amyloidosis↗
PubMed1979

Effects of antimycin A and 2-deoxyglucose on secretion in human platelets. Differential inhibition of the secretion of acid hydrolases and adenine nucleotides.

1. Shape change, aggregation and secretion of dense-granule constituents in platelets differ in their dependence on cellular energy metabolism. The possibility that such a difference also exists between secretion of dense-granule constituents and acid hydrolases was investigated. 2. Human platelets were incubated with [(14)C]adenine in plasma, and then washed and resuspended in salt solutions. The effects of incubating the cells with antimycin A and 2-deoxyglucose on the concentrations of [(14)C]ATP, ADP, AMP, IMP and inosine plus hypoxanthine and on thrombin-induced secretion of ATP plus ADP and acid hydrolases were studied. The metabolic inhibitors only affected (14)C-labelled nucleotides, whereas thrombin only liberated unlabelled ATP and ADP. 3. The extent of secretion decreased progressively with time during incubation with the metabolic inhibitors. At any time the secretion of acid hydrolases, beta-N-acetylglucosaminidase, beta-glucuronidase and beta-galactosidase was inhibited to a greater extent than secretion of ATP plus ADP (dense-granule secretion). 4. Incubation with the metabolic inhibitors shifted the log (dose)-response relationship to higher thrombin concentrations, and with a greater shift for acid hydrolase secretion than for dense-granule secretion. 5. Antimycin, when present alone, caused a marked decrease in the rate of acid hydrolase secretion, but had no effect on dense-granule secretion. 6. These results further support the view that acid hydrolase secretion and dense-granule secretion are separate processes with different requirements for ATP energy. Acid hydrolase secretion, but not dense-granule secretion, appears to depend on a simultaneous rapid generation of ATP, which can be accomplished by oxidative, but not by glycolytic, ATP production.

Adenine Nucleotides↗
PubMed1977

Spurious prolongation of the activated partial thromboplastin time.

The clinical and laboratory data of 8 patients (4 males and 4 females) with circulating anticoagulant were presented. Based on prolonged APTT, failure to correct the APTT with 50% normal plasma and abnormal tissue thromboplastin inhibition test, the inhibitor was identified as "middle stage"--or the "lupus anticoagulant". Thrombokinetics showed the maximal rate of change in optical density (VmaxdeltaOD) of plasma, resulting from clot formation to be significantly less in the plasma of patients with the inhibitor than in normal plasma. This was not completely corrected by mixing the patients' plasma with 50% normal plasma.

Adult↗
PubMed1977

A system of extension prostheses.

It is suggested that three basic types of extension prostheses are required as shown in Figure 1. Four methods of achieving these prescriptions using rigid, total-contact, polyester laminate sockets have been described, and the table (Fig. 6) indicates the correct method to be used for each type. These prostheses have proved very durable and repairs have been limited to replacing the straps and foot coverings. Advantages claimed are improved comfort, efficiency, and appearance, in addition to speed of fabrication and lightness when compared with conventional prostheses.

Adult↗
PubMed1976

Metabolic aspects of the secretion of stored compounds from blood platelets. V. Effect of ionophore A23187 on washed platelets.

1. The A23187-induced secretion of preabsorbed serotonin from human blood platelets at 37 degrees C is studied. Preincubation at the same temperature before the addition of ionophore is necessary for maximal release induction. When total incubation time is kept constant, longer time with ionophore results in a smaller decrease in the level of metabolic ATP and increase in metabolic ATP and increase in metabolic IMP. This coincides with the reduction in secretion, but statistical treatment of the results suggests that the reduced secretion only partially explains the reduced drop in metabolic ATP, and that therefore a resynthesis of metabolic ATP from IMP may have taken place. 2. In some experiments induction of secretion takes place over a very narrow range of ionophore concentration. 3. When K+ substitutes for Na+ in the extracellular medium, the need for preincubation for maximal secretion becomes less evident, and at times is abolished, while there is still a significant increase in the metabolic ATP level by prolonged incubation with ionophore. 4. A reduction in secretion is observed with metabolic blockers when the ionophore is added after preincubation, but to a much less degree than when secretion is induced by thrombin, in spite of a great reduction in the level of metabolic ATP. This may partly be explained by the increase in secretion induction by A23187 in the presence of inhibitors when the ionophore is added in the cold, suggesting that the inhibitor may cause "weakening" of the platelets' "resistance" to induction of secretion by ionophore. 5. When the effect of Ca2+ and of Mg2+ on the level of intermediates of the TP leads to hypoxanthine conversion is studied, it is evident that the addition of Ca2+ causes enhanced IMP accumulation and a reduction in the level of inosine plus hypoxanthine, while Mg2+ has the opposite effect. This suggests that the two metals affect the enzymes of the IMP leads to hypoxanthine conversion differently. 6. Indomethacin inhibits secretion induced by A23187, suggesting that prostaglandin intermediates may amplify the ionophore-induced release. The adenine nucleotide metabolism is not affected. 7. The results indicate that there is an indirect, rather than direct, link between the major metabolic changes and the secretion induced by A23187, but that the ionophore may cause intracellular changes which are not connected to its effect as release inducer.

Adenine↗
PubMed1976

Metabolic aspects of the secretion of stored compounds from blood platelets. IV. Effects of ionophore X537A on washed platelets.

1. X537A at concentrations below 10 muM can liberate platelet serotonin from washed human platelets without inducing the platelet release reaction. Up to 100% of serotonin preabsorbed by the platelets can be liberated before initiation of the release reaction. 2. Concentrations of X537A above 10muM initiate the platelet release reaction, with a maximum release of adenine nucleotides and platelet factor 4 antigen comparable to that obtained with 1.25 units thrombin/ml. 3. The changes in ATP metabolism at the concentration necessary for X537A-induced release are more profound than those in platelets exposed to concentrations of thrombin or A23187 giving the same degree of release, and approach those seen with high concentrations of A23187. At concentrations where serotonin is liberated but no adenine nucleotide or platelet factor 4 antigen is released, short time incubation causes no change in the level of metabolic ATP.

Adenine Nucleotides↗
PubMed1975

Calcium ionophore A23187 (Eli Lilly): effect on platelet function, structure and metabolism.

The addition of 0.1 muM ionophore A23187 to washed platelets incubated in citrated saline caused massive release of stored serotonin accompanied by intracellular accumulation of inosine monophosphate, but produced no detectable influx of externally added calcium or abnormal structural alterations. With increasing ionophore concentration there was a significant influx of calcium and a drastic alteration in the platelet ultrastructure. The increase in ionophore concentration was accompanied by the conversion of the major part of metabolic adenine nucleotides to inosine monophosphate and an almost complete blockage of further conversion to inosine and hypoxanthine. The metabolic changes were accentuated by the addition of calcium at concentrations less than 1/10 of the citrate concentration. In the presence of Ca++, or when citrate was omitted, there was a substantial leakage of cytoplasmic material, which at times suggested complete exchangeability between cytoplasm and extracellular medium. Our findings are consistent with the hypothesis that the platelet release reaction is triggered by intracellularly bound calcium. They also suggest that the application of high ionophore concentration has a toxicologic rather than a physiologic effect on platelets, and that a weak chelator added during incubation with the ionophore can in the absence of divalent cations prevent cell destruction, but not the toxic effect on cell metabolism.

Adenine Nucleotides↗
PubMed1975

The role of thrombin in ADP-induced platelet aggregation and release: a critical evaluation.

The role of thrombin in ADP-induced aggregation and release in vitro was critically examined. The addition of heparin or hirudin to citrated platelet rich plasma did not prevent aggregation or release. The addition of citrate to heparinized plasma restored secondary aggregation and release. Hirudin did not prevent irreversible aggregation. These results are incompatible with the hypothesis that thrombin is a primary and necessary mediator of platelet aggregation (Ardlie & Han, 1974; Han & Ardlie, 1974a, b, c). This hypothesis is based in part on the assumption that EDTA enhances the elution of clotting factors from platelets; we found no enhanced elution of factors II, V, X, VIII, IX or XI when platelets were washed in EDTA.

Adenosine Diphosphate↗
PubMed1975

Short communication: possible association of newly absorbed serotonin with nonmetabolic, granule-located adenine nucleotides in human blood platelets.

[3H]-adenine-labeled human platelets in plasma were incubated with or without nonradioactive serotonin. Release reaction was then induced by ADP, epinephrine, collagen, or thrombin. Platelets that had been incubated with serotonin released four times as much serotonin as platelets incubated without serotonin. The specific radioactivities of the ATP and ADP released to plasma during release reaction induced with all four inducers were the same in both systems. This shows that when serotonin is taken up by human platelets, it enters the compartment containing nonmetabolic, granula-stored ATP, and not the compartment with metabolic extragranular ATP. These results suggest that the mechanism of serotonin storage in human platelets is similar to that in other species investigated, i.e., rabbit, guinea pig, and pig.

Adenine↗