Suxamethonium in bunged cannulae.
Explore the source record for details and available documents.
Apnea↗
Biomedical subjects
L Walker
Publications and source records attributed to L Walker.
Activation of mouse peritoneal macrophages by maintenance in serum-free medium.
Normal mouse peritoneal macrophages maintained in a serum-free medium for 48-72 h and then stimulated with phorbol myristate acetate, zymosan or bacteria, released large amounts of hydrogen peroxide. Opsonized zymosan and bacteria stimulated greater release than their unopsonized counterparts. Enhanced peroxide production was not a consequence of increased uptake of particles. Addition of serum to the serum-free medium abolished activation. The addition of interferon-gamma to the serum-free medium enhanced the effect of the serum-free treatment of macrophages from C3H/HeJ mice but abolished the effect of serum free treatment of macrophages from CFLP mice. The results are discussed in terms of negative regulation of receptor-oxidase linkage by serum.
Animals↗
Effect of rapid alteration in glucose concentration and insulin on thymidine uptake in bovine retinal capillary endothelium.
The effect of insulin and rapid changes in glucose concentration on bovine retinal capillary endothelium (BRCE) was examined by use of tissue culture and 3H-thymidine incorporation. In the absence of insulin, no effect on thymidine uptake by BRCE was observed when glucose concentration was rapidly altered, either increased or decreased. The stimulating effect of insulin on retinal capillary endothelin was more pronounced in log-phase cells than in stationary-phase cells. The extent of stimulation by insulin decreased with increasing glucose concentrations. This effect was not observed when osmotic pressure was increased by mannitol. The results of our experiments make it unlikely that altered osmotic stress, rapidly changing or abnormal glucose levels would be primarily responsible for altered endothelial activity.
Animals↗
Identification of an HSV-1/HSV-2 cross-reactive T cell determinant.
The results from a number of studies have documented that the HSV glycoprotein gD is an important target for neutralizing antibodies. In contrast, little is known about the Th cell determinants present on HSV that are required for anti HSV gD antibody production. In our study we have immunized BALB/c mice with a recombinant source of HSV-1 gD lacking the carboxyl-terminal 93 amino acids. T cell hybridomas produced from the immunized animals recognized a single antigenic peptide (amino acids 246-261) in the context of I-Ad. The determinant expressed by gD peptide 246-261 was generated and presented by both HSV-1 and HSV-2 infected APC. Fine specificity analysis using truncated synthetic gD peptides revealed that the minimal amino acids recognized by the T hybrids were identical between HSV-1 and HSV-2. In addition, the minimal peptide-I-Ad binding analysis demonstrated that the minimal peptide sequence required for the binding to I-Ad and for T cell recognition contained two prolines. Thus, this important HSV antigenic determinant would not be expected to form an amphipathic alpha-helix and could therefore be missed by algorithms currently used to predict which amino acid sequences would be antigenic based on the propensity to form helices.
Amino Acid Sequence↗
Characterization of the specificity of peptide binding to four DR haplotypes.
This study describes the establishment of a peptide-binding assay for purified, detergent-solubilized DR molecules. For each of the DR specificities and peptides studied, a unique pattern of interaction was observed. Excellent correlation was detected between the DR1-, 2-, 5-, and 52a-binding capacities and the known DR restrictions of a panel of synthetic peptides. This supports the immunologic relevance of the binding assay, and emphasizes the importance of determinant selection in defining the immune response of individuals. We have also examined the capacity of a panel of DR-restricted peptides to compete with one another for binding to DR1. The results obtained are compatible with a single peptide-binding site on DR molecules. The peptide-binding capacity of the four different DR types (DR1, DR2, DR5, and DR52a) has been further examined by testing a collection of 133 different peptides. This collection is unbiased with respect to previously known DR binding and restrictions, and includes peptides of eukaryotic, bacterial, and viral origins. It was found that: 1) approximately 15 to 35% of the peptides tested bound any given DR type; 2) DR-binding capacities appeared to correlate with each other, suggesting that different alleles of the DR isotype may recognize related structures on an Ag molecule; and 3) despite the statistical correlation between binding capacity of different DR types, approximately 50% of the peptides that were positive binders still were specific in that they could bind only one of the four DR molecules tested. Degenerate binding (i.e., binding to most or all the DR molecules tested) was detected in only a minority of the cases analyzed (approximately 25%).
Amino Acid Sequence↗
Characteristic immunophenotyping artefact seen in patients with anti-mouse immunoglobulin antibodies.
Patients treated with murine monoclonal antibodies develop anti-mouse immunoglobulin antibodies which can interfere with flow cytometry of lymphocytes, giving rise to high levels of nonspecific staining. This artefact can be avoided by using separated, washed lymphocytes for immunophenotyping.
Animals↗
The effect of glucose and insulin concentration on type IV collagen biosynthesis by bovine retinal capillary endothelial cells in vitro.
Qualitative and quantitative analyses of type IV collagen, newly synthesized by cultured retinal capillary endothelial cells were carried out. After 24-hour incubation in high glucose (25 mM) media with 14C proline there was less type IV collagen synthesis than after incubation in 5.6 mM glucose media. Insulin stimulated the biosynthesis of type IV collagen in both low and high glucose concentrations. The stimulating effect of insulin (on the biosynthesis of type IV collagen) was still observed after inhibition of cell growth with hydroxyurea. High ambient glucose and the insulin effect could play a role in the structural changes observed in diabetic retinal microvascular basement membranes.
Animals↗
Differences in affinity of anti-CD4 monoclonal antibodies predict their effects on syncytium induction by human immunodeficiency virus.
A panel of 20 anti-CD4 monoclonal antibodies (mAb) was ranked in terms of affinity, using an inhibition radioimmunoassay. The ability of these antibodies to inhibit the induction of syncytia by human immunodeficiency virus (HIV) and to prevent binding of the HIV envelope glycoprotein 120 (gp120) to CD4 was also measured. Syncytium inhibition correlated strongly with affinity (P less than 0.001) but only weakly with inhibition of gp120 binding (P = 0.038). Some antibodies partially blocked binding of gp120 to CD4 but did not inhibit syncytia, and some antibodies inhibited syncytia but only weakly blocked binding of gp120. These results suggest that the syncytium inhibition assay is highly affinity-dependent, and that epitopes on CD4 concerned with virus binding are distinct from those involved in syncytium formation.
Antibodies, Monoclonal↗
Initial hormonal and metabolic profile in critically ill patients with community-acquired lobar pneumonia.
A prospective study of 18 critically ill patients with community-acquired lobar pneumonia was undertaken at Hillbrow Hospital, Johannesburg, in order to document the initial plasma hormonal and substrate profile as part of the stress response to the infection. The results of these studies, carried out before therapy, were compared with the results in a group of healthy fasting adults. Highly significant (P less than or equal to 0.005) increases in the mean plasma levels of adrenaline, noradrenaline, human growth hormone, cortisol, glucose and free fatty acids were noted in the study group, with a lesser increase in the prolactin concentration (P less than or equal to 0.01). The levels of dopamine, glucagon, insulin and adrenocorticotrophin did not show any significant change. No significant differences were found in the hormonal profile when comparing survivors with non-survivors. The neuro-endocrine hormonal and metabolic responses in pneumonia appear to be similar to those seen in other stress situations and failure of the initial stress response does not appear to contribute to the mortality of critically ill patients with community-acquired lobar pneumonia.
Adult↗
Association of a Ras-related protein with cytochrome b of human neutrophils.
Activation of the superoxide generating system in human neutrophils is thought to involve the interaction or assembly of cytochrome b with other cytosolic and membrane proteins. We have now co-isolated by conventional purification procedures a protein of relative molecular mass 22,000 with cytochrome b. This Ras-related protein is not a fragment of either of the subunits of cytochrome b, and its primary structure, as determined by the sequencing of its complementary DNA, is identical to that predicted from a recently cloned ras-related gene, rap1 (also termed Krev-1). Immunoaffinity purification on anti-cytochrome and anti-Ras immunoaffinity matrices indicates an association between cytochrome b and the Ras-related protein. The association of a Ras-related GTP-binding protein with cytochrome b of human neutrophils could indicate a role for such a protein in the transduction, regulation or structure of the superoxide generating system.
Amino Acid Sequence↗
Three hundred admissions to the Waikato Hospital intensive therapy unit--survival, costs, and quality of life after two years.
Three hundred consecutive admissions 13 years of age and above who entered the Waikato Hospital intensive therapy unit, were followed up after two years. Their degree of illness was similar to that in other intensive care units. At two years, 26% of the patients were dead. Maori admissions and death rates more than doubled those of the nonMaori. Once admitted, the proportion dying was identical in both groups. The average stay in ITU was 6.3 days. The average stay in hospital including ITU, was 28 days. One hundred and fifty-nine people (168 admissions) were traced and questioned about their quality of life. Seventy-four percent had a good quality, 19% were affected, and 7% had a severely affected quality of life. Preliminary estimates of cost suggest that the average ITU cost per patient is about $9500, and the average total hospital cost for any patient entering ITU is about $20,000.
Adolescent↗
Study of human epithelial cell detachment and damage: development of a model.
Detachment of epithelial structures from underlying basement membrane (BM) represents an important component of a number of human disease processes e.g. airway and alveolar diseases, gastrointestinal ulceration, and retinal diseases. This study describes a method of evaluating human epithelial cell detachment from BM that is simple, rapid, inexpensive, quantifiable and which, because it utilizes BM rather than tissue culture plastic, more closely mimics the in vivo situation than other methods. In this model human amnionic epithelial cells attached to their underlying BM are isolated from fresh placentae and mounted in a multi-well chemotaxis assembly. These membranes can be studied with the epithelial cell monolayer intact. Protease-induced detachment of the epithelial cells from the underlying BM was readily quantifiable using light microscopy and spectroscopy. Following removal of the native amnionic epithelial cells, immunoperoxidase staining for the BM attachment proteins laminin, fibronectin, and type IV collagen demonstrated that these molecules remain intact. The BM could also be used as an attachment surface to reconstitute other epithelial cell monolayers. Cultured human amnionic cells and human respiratory epithelial cells were both able to attach to the denuded BM in the absence of serum (% attachment = 85 +/- 15% and 92 +/- 8% respectively, P = 0.8). Natural BM was a better substrate for epithelial cell attachment than tissue culture plastic in that, in the absence of serum, cultured epithelial cell attachment to tissue culture plastic was 20 +/- 4% of the value for BM (P less than 0.05). Furthermore, cells attached to plastic adhered less effectively than to BM in that trypsin concentrations required to induce 50% cell detachment were 0.72 +/- 0.4 for plastic and 62 +/- 13 BAEE U/ml for BM (P less than 0.001). In view of the complex protein interactions known to be involved in the anchorage of human epithelial cells to BM, it is likely this model will be a useful tool for evaluating the mechanisms underlying human epithelial cell attachment and detachment in a variety of normal and disease situations.
Amnion↗
Maternal milk and plasma glucose and insulin levels: studies in normal and diabetic subjects.
The relationship between maternal glucose levels and the concentration of glucose and insulin levels in human milk from diabetic women has not been elucidated. In addition, the rate of appearance of intravenously injected insulin to the change in concentration of insulin in maternal milk has not been studied. To study this relationship of glucose levels in serum to glucose levels in milk, maternal milk and glucose levels were measured in diabetic lactating women (n = 7) and nondiabetic lactating women (n = 10). In addition, the change in milk concentration of insulin was studied after an intravenous injection of insulin. The maternal whole blood glucose in the seven diabetic women was stabilized at a baseline blood glucose of approximately 100 mg/dl and then elevated with an infusion of intravenous glucose to a level of three times baseline (approximately 300 mg/dl for up to 2 hours). The plasma glucose was then lowered back to baseline with intravenous insulin over 20 minutes. The baseline serum insulin and glucose levels were compared to nonlactating women who donated serum to measure insulin levels in normal controls. Maternal milk glucose levels rise following an increase of plasma glucose levels with a lag time to the peak glucose level of 40-90 minutes, and return to baseline following the return of plasma glucose to baseline with a lag time of 120-150 minutes. Baseline milk insulin levels are elevated in hyperinsulinemic women and the levels of insulin in the milk will rise dramatically above baseline values after an intravenous injection of insulin with a lag time to the peak of concentration in milk of 60-80 minutes.(ABSTRACT TRUNCATED AT 250 WORDS)
Adult↗
Effects of formal support on mothers' adaptation to the hospital-to-home transition of high-risk infants: the benefits and costs of helping.
94 mothers were randomly assigned to a control group or to a group who received a formal support program designed to aid their adaptation to the transition from hospital to home care of high-risk infants. Mothers' predischarge need for support and the severity of infants' predischarge medical problems moderated program effects assessed 6 months after NICU discharge. Positive effects of the program on mothers' sense of competence, perceived control, and responsiveness were evident for mothers who had needed the most support. But at low levels of need for support, participation in the program had negative effects on these outcomes. A similar pattern was found for the effects of the program on mothers' positive mood as a function of the severity of infants' medical problems. Secondary findings suggest why some mothers may benefit from formal support after NICU discharge and others may experience at least temporary disruptions in their adaptation from such support.
Cost-Benefit Analysis↗
Dialogue on a theoretical issue: the future of theory development--commentary and response.
Explore the source record for details and available documents.
Humans↗
Characterization, activation, and functional importance of mucosal mast cells.
Explore the source record for details and available documents.
Animals↗
Circumstances of sexual and physical victimization of black psychiatric outpatients.
A sample of 54 adult psychiatric outpatients, previously identified as victims of sexual or physical assault, were interviewed regarding their childhood and adult victimization experiences. Patients were questioned about the nature of the assaults, their relationship to the perpetrator(s), the number of assaults suffered in each relationship, and whether the assault(s) occurred before or after the onset of their mental illness. Eighty percent of the sample had experienced major physical assault as an adult and 59% had experienced major physical assault as a child; 37% and 31%, respectively, reported major sexual assault as a child and as an adult. Women were more likely than men to report physical and sexual assault as an adult and sexual assault as a child. Childhood assault most often occurred before the onset of the patient's mental illness; whereas, adult sexual assault for women and physical and sexual assault for men was as likely to occur after the onset of the psychiatric disorder, suggesting an increased vulnerability to victimization for the adult mentally ill.
Adult↗
Intravesical chemotherapy: combination with dimethyl sulfoxide does not enhance cytotoxicity in vitro.
There is evidence that dimethyl sulfoxide (DMSO) can increase the anticancer activity of chemotherapeutic drugs. As DMSO is instilled into the bladder for interstitial cystitis, it could be readily adopted in clinical practice if it was found to enhance the effectiveness of the drugs used for intravesical chemotherapy. The purpose of this study was to investigate, using a human bladder cancer cell line, the hypothesis that DMSO enhances the activity of these agents. However, the addition of 4% DMSO to the four drugs most frequently used for intravesical chemotherapy (adriamycin, epodyl, mitomycin-c, thiotepa) did not increase tumour cell kill in vitro.
Administration, Intravesical↗