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B J Anderson

Publications and source records attributed to B J Anderson.

At least 19 recordsLinked to original sources
PubMed1996

Cucumber mosaic virus RNA 5 is a mixed population derived from the conserved 3'-terminal regions of genomic RNAs 2 and 3.

Analysis of encapsidated RNA from the Q strain of CMV (Q-CMV) has indicated the presence of a discreet population of molecules of approximately 300 nt termed RNA 5 (Peden, K.W.C., and Symons, R.H., Virology 53,487-492, 1973.). Q-CMV RNA 5 was isolated and the 5'-end sequence was determined by direct RNA sequencing. This sequence corresponded to the exact beginning of the imperfectly conserved 3'-terminal region of genomic RNAs 1, 2, and 3. A probe generated from RNA 3 consisting of the last 130 nt of this region hybridised to RNA 5. Oligonucleotides containing sequences from the 5'- and 3'-ends of the conserved region were used to generate RNA 5 cDNA clones by RT-PCR on gel-purified RNA 5. Sequencing of these clones and primer extension analysis of transcripts (derived from the cDNA clones) and purified RNA 5 indicated that RNA 5 consists of the conserved 3'-terminal region of genomic RNAs 2 and 3.

Base Sequence↗
PubMed1995

RNA 4 sequences from cucumber mosaic virus subgroups I and II.

The complete sequences of RNA 4 from cucumber mosaic virus (CMV) strains Ny (subgroup I) and Sn (subgroup II) have been determined and compared to all other known complete CMV RNA 4 sequences. The identification of a unique EcoRI site, present only in subgroup-II RNA 4 sequences, provides the basis for a simple method of classifying CMV isolates.

Base Sequence↗
PubMed1995

Risk of thromboembolism with the aortic Carpentier-Edwards bioprosthesis.

Porcine bioprostheses provide an excellent alternative to mechanical prostheses for heart valve replacement in patients unable to comply with systemic anticoagulation and in the elderly. Long-term results of this prosthesis, however, demonstrated identical survival and parallel event-free status, albeit at a lower rate than the mechanical valves. Some discrepancy exists as to the need for and duration of systemic anticoagulation in the bioprosthesis, and some evidence exists to contraindicate anticoagulation due to a higher late mortality rate in patients with an aortic bioprosthesis. The records of 561 patients having the Carpentier-Edwards bioprosthesis in the aortic position as an isolated valve procedure were reviewed. The overall rate of bioprosthetic failure events was low (0.23%/patient year) and the survival (5 year, 74.8 +/- 2.4%; 10 year, 52.9 +/- 4.9%) and event-free statistics (5 year, 67.9 +/- 2.6%; 10 year, 42.4 +/- 5.1%) were excellent. No gender difference was present. A vulnerable period for neurologic events was identified by hazard function whereby the incidence of stroke was high; these were increased in the patient variables of compromised ejection fraction (0.54; p < or = 0.003), older age (< or = 73 years; p < or = 0.02), and preoperative atrial fibrillation or paced rhythm (p < or = 0.01). This pattern was similar for both transient ischemic events and strokes and rapidly decreased over the first few months of the first year and the first few years of the 12-year follow-up. These patients were not routinely anticoagulated.(ABSTRACT TRUNCATED AT 250 WORDS)

Actuarial Analysis↗
PubMed1995

Results of an autologous tissue reconstruction for replacement of obstructed extracardiac conduits.

Between May 1983 and March 1, 1995, 50 patients had replacement of an obstructed pulmonary ventricle-pulmonary artery conduit with an autologous tissue reconstruction in which a prosthetic roof was placed over the fibrous tissue bed of the explanted conduit. The roof was constructed with xenograft pericardium (most recently) (n = 42), homograft dura mater (n = 5), or Dacron fabric (n = 3). Patient ages ranged from 5 to 34 years (median 16 years). The explanted conduits were Hancock conduits (n = 33), Tascon conduits (n = 6), homograft (n = 4), Dacron tube (n = 3), and others (n = 4). Preoperative maximum systolic gradients ranged from 44 to 144 mm Hg (median 78 mm Hg). Thirty-seven concomitant cardiac procedures were done in 29 patients. When a valve was necessary (n = 15), it was possible to place a large-sized valve in the autologous tissue reconstructions (range 22 to 29 mm, median 26 mm). Cardiopulmonary bypass times ranged from 34 to 223 minutes (median 84 minutes), and aortic crossclamp times ranged from 0 (in 32 patients) to 109 minutes (median 0 minutes). Intraoperative postrepair peak systolic gradients from pulmonary ventricle to pulmonary artery ranged from 0 to 33 mm Hg (median 13 mm Hg). There was one early death (2%) in a patient who had additional cardiac procedures. Follow-up was complete in all patients and ranged from 1 month to 11.8 years (median 7.5 years). There were two sudden late deaths: conduits in both were known to be free from obstruction. Forty-four of the 47 surviving patients had evaluation of the gradient by echocardiography or cardiac catheterization 1 month to 11 years (median 7 years) after operation. The gradients ranged from 5 to 45 mm Hg (median 20 mm Hg). None of the conduits developed an obstructive peel, valve obstruction, or valve incompetence. At 10 years, the freedom from reoperation for conduit obstruction was 100%, and freedom from reoperation for any cause was 81%. This technique simplifies conduit replacement, allows for a generous-sized outflow tract, has a low risk, and yields late results that appear superior to those of cryopreserved homografts or other types of extracardiac conduits.

Adolescent↗
PubMed1995

The risk of stroke in the early postoperative period following mitral valve replacement.

All patients (285) undergoing mitral valve replacement (MVR) with a Carpentier-Edwards (C-E) bioprosthesis +/- coronary bypass grafts (CABG) were reviewed (109 men and 176 women with a median age of 70 years). Overall, the 5-year survival rate was 58.9%, 62.7% for MVR (199 patients) and 50.1% for MVR+CABG (86 patients). Late survival was adversely affected by the operative time variables of NYHA class IV, older (> or = 70 years) age, low (> or = 56%) ejection fraction (EF), and the additional performance of associated procedures+CABG with MVR (P < or = 0.001). The 5-year freedom from stroke rate was 89.2%, 89.1% for MVR and 90.2% for MVR +/- CABG. Advanced heart class was the only significant variable associated with a greater risk of late stroke (P < or = 0.01). Neither chronic preoperative atrial fibrillation nor operative obliteration of the left atrial appendage increased or decreased the late risk of stroke in patients following MVR. Hazard function for stroke occurring in the first postoperative year (first 48 h excluded to discount intraoperative events) demonstrated the highest rate within the first month (40%), rapidly diminishing thereafter. This pattern was reproduced in the 12-year hazard function in that the rate of stroke occurrence was greatest in the first year (6.7%) following implantation. The mean stroke rate over 12 years was 2.5%. Strokes following MVR +/- CABG are more likely to occur in older and more compromised patients, and the higher early rate is not reflected in the mean rate. A more aggressive approach to early anticoagulation with IV heparin, Coumadin, and possibly antiplatelet therapy is advocated to reduce this complication rate.

Adolescent↗
PubMed1995

Future directions for research on pediatric chronic disease management: lessons from diabetes.

Discussed conceptual and methodological issues related to research on the management of pediatric chronic disease, focusing on diabetes. The quality of studies in this area has improved, but several problems remain. Recommendations include greater use of theory in planning studies; population-based samples; more sophisticated definitions of adherence; longitudinal designs; and analyses that control for demographic, developmental, and medical variables. Most needed are prevention and intervention studies that modify (rather than simply describe) contextual, behavioral, and psychological variables hypothesized to facilitate or impede adherence and adjustment. The questions asked and designs employed should match the state of knowledge regarding the conceptual issue(s) being studied. It is often not possible for a given study to incorporate all of the recommendations above, but it is hoped that more research studies will move toward these goals, and thereby enhance the contribution of pediatric psychology to chronic disease management.

Adolescent↗
PubMed1995

Pharmacokinetics of rectal paracetamol after major surgery in children.

Glycogelatin capsular suppositories containing a paracetamol slurry 40 mg.kg-1 were given PR to 20 children (12 months-17 yrs) after major orthopaedic surgery and plasma concentrations of paracetamol measured for up to 18 h. The mean maximum concentration (Cmax) was 0.115 (SD 0.049) mmol.l-1. Peak concentration occurred (Tmax) at 2.3 (SD 1.2) h. Mean concentration was 0.07 (SD 0.03) mmol.l-1 at six h. Apparent paracetamol clearance was 5.8 ml.min-1.kg-1. The plasma concentration of paracetamol associated with analgesic effectiveness in children is unknown, but antipyretic effects are seen in the range 0.066-0.130 mmol.l-1. Paracetamol suppositories 40 mg.kg-1 given perioperatively achieve effective therapeutic antipyretic plasma concentrations within 1-2 h. The timing is coincident with the recovery phase of short duration paediatric surgery. The coefficient of variance of Cmax was 43%. Some individual patients may not achieve a Cmax which is therapeutic.

Acetaminophen↗
PubMed1995

Assessment of diabetes-related distress.

OBJECTIVE: To describe a new measure of psychosocial adjustment specific to diabetes, the Problem Areas in Diabetes Survey (PAID), and to present initial information on its reliability and validity. RESEARCH DESIGN AND METHODS: Before their routine clinic appointments, 451 female patients with type I and type II diabetes, all of whom required insulin, completed a self-report survey. Included in the survey was the PAID, a 20-item questionnaire in which each item represents a unique area of diabetes-related psychosocial distress. Each item is rated on a six-point Likert scale, reflecting the degree to which the item is perceived as currently problematic. A total scale score, hypothesized to reflect the overall level of diabetes-related emotional distress, is computed by summing the total item responses. To examine the concurrent validity of the PAID, the survey also included a series of standardized questionnaires assessing psychosocial functioning (general emotional distress, fear of hypoglycemia, and disordered eating), attitudes toward diabetes, and self-care behaviors. All subjects were assessed for HbA1, within 30 days of survey completion and again approximately 1-2 years later. Finally, long-term diabetic complications were determined through chart review. RESULTS: Internal reliability of the PAID was high, with good item-to-total correlations. Approximately 60% of the subject sample reported at least one serious diabetes-related concern. As expected, the PAID was positively associated with relevant psychosocial measures of distress, including general emotional distress, disordered eating, and fear of hypoglycemia, short- and long-term diabetic complications, and HbA1, and negatively associated with reported self-care behaviors. The PAID accounted for approximately 9% of the variance in HbA1. Diabetes-related emotional distress, as measured by the PAID, was found to be a unique contributor to adherence to self-care behaviors after adjustment for age, diabetes duration, and general emotional distress. In addition, the PAID was associated with HbA1 even after adjustment for age, diabetes duration, general emotional distress, and adherence to self-care behaviors. CONCLUSIONS: These findings suggest that the PAID, a brief, easy-to-administer instrument, may be valuable in assessing psychosocial adjustment to diabetes. In addition to high internal reliability, the consistent pattern of correlational findings indicates that the PAID is tapping into relevant aspects of emotional distress and that its particular feature, the measurement of diabetes-related emotional distress, is uniquely associated with diabetes-relevant outcomes. These data are also consistent with the hypothesis that diabetes-related emotional distress, separate from general emotional distress, is an independent and major contributor to poor adherence. Given that the study was limited to female patients using insulin, further examination of the clinical usefulness of the PAID will need to focus on more heterogeneous samples.

Adult↗
PubMed1995

Late results of pulmonary ventricle to pulmonary artery conduits.

The development of the extracardiac conduit has been one of the greatest advances in cardiac surgery. Conduits have decreased the mortality rate of several standard operations and have made possible the correction of numerous complex congenital cardiac anomalies that previously were uncorrectable. However, the ideal conduit has not yet been developed. We have reviewed the long-term (16 to 29 years) results of our early experience with this technique.

Adolescent↗
PubMed1994

Glial hypertrophy is associated with synaptogenesis following motor-skill learning, but not with angiogenesis following exercise.

Rats reared from weaning in a complex environment have an increase in 1) glial surface area, 2) capillary volume, and 3) the number of synapses, per neuron. In that paradigm it has not been possible to determine whether the glial increase more closely correlates with the increase in synaptic numbers or with angiogenesis. More recently we have found that rats that exercised had an increase in the density of capillaries without an increase in the synaptic numbers, whereas rats that learned new motor skills had a greater number of synapses per neuron without an increase in the density of capillaries. Those findings provided the opportunity to investigate whether changes in glial volume in the cerebellum correspond to changes in the number of synapses or in capillary volume. Glial area fraction estimates were obtained using point counts on electron micrographs from the previous studies. The skill learning group had a greater volume of molecular layer per Purkinje cell, and also a greater volume of glia per Purkinje cell, than rats in either an inactive group or rats in two exercise groups. No significant differences were found in glial volume per synapse and glial volume per capillary across groups, although there was a tendency for glial volume per capillary to be lower in the exercise groups. The data indicate that glial volume correlates with synaptic numbers and not with capillary density.

Animals↗
PubMed1994

New overlapping gene encoded by the cucumber mosaic virus genome.

Cucumber mosaic virus (CMV) contains three genomic RNAs (RNAs 1, 2, and 3) and a subgenomic RNA (RNA 4), a shared feature of the Bromoviridae family which includes cucumoviruses, bromoviruses, alfalfa mosaic virus, and ilarviruses. We describe in this paper the molecular characterization of a novel subgenomic RNA of the Q strain of CMV (Q-CMV), RNA 4A, which was first reported in 1973 (K. W. C. Peden and R. H. Symons, Virology 53, 487-492, 1973). RNA 4A is 682 nucleotides and is identical in sequence to the 3'-terminal 682 nucleotides of RNA 2. RNA 4A encodes a small open reading frame (ORF) of 100 codons, which, in RNA 2, overlaps the C-terminal portion of the major 2a gene; thus it is likely that RNA 4A functions as the mRNA for the in vivo expression of the ORF, called ORF 2b. Polyclonal antibodies raised against a 2b fusion protein expressed in Escherichia coli specifically detected the 2b gene product in Q-CMV-infected cucumber plants by Western immunoblotting. Examination of published viral RNA sequences revealed the conservation of ORF 2b in all of the four other cucumoviruses sequenced to date; however, it is absent from the rest of the Bromoviridae. We suggest that the proposed ORF 2b may be expressed in other cucumoviruses, most likely via 4A-like subgenomic RNAs, and that the predicted gene product may have a unique functional role in the infection process of cucumoviruses.

Amino Acid Sequence↗
PubMed1994

Insulin omission in women with IDDM.

OBJECTIVE: To describe the extent of intentional insulin omission in an outpatient population of women with insulin-dependent diabetes mellitus (IDDM) and examine its relationship to disordered eating, attitudes toward diabetes, other psychosocial factors, long-term complications, and glycemic control. RESEARCH DESIGN AND METHODS: Before their routinely scheduled clinic appointments, female IDDM patients who were 13-60 years of age completed a self-report survey (final n = 341). The survey included standardized questionnaires assessing disordered eating attitudes and behaviors, psychological functioning (general distress, diabetes-specific distress, and hypoglycemic fear), attitudes toward diabetes, and self-care behaviors. All subjects were assessed for glycosylated hemoglobin within 30 days of survey completion. Long-term complications were determined through chart review. RESULTS: Approximately 31% of the subject sample, representing women of all ages, reported intentional insulin omission, but only 8.8% reported frequent omission. Compared with non-omitters, omitters reported more disordered eating, greater psychological distress (general and diabetes-specific), more hypoglycemic fear, poorer regimen adherence, and greater fears concerning improved diabetes management (which may lead to weight gain). Omitters evidenced poorer glycemic control, more diabetes-related hospitalizations, and higher rates of retinopathy and neuropathy. Multivariate examination revealed only two variables that independently predicted omission: diabetes-specific distress and fear of improved glycemic control ("because I will gain weight"). Of the omitters, approximately half reported omitting insulin for weight-management purposes (weight-related omitters). These subjects evidenced significantly greater psychological distress, poorer regimen adherence (including more frequent omission), poorer glycemic control, and higher rates of complications than did non-weight-related omitters as well as non-omitters. Non-weight-related omitters tended to fall between weight-related omitters and non-omitters on most measures of psychological functioning, adherence, and glycemic control. CONCLUSIONS: These findings suggest that insulin omission is common, that it is not limited to younger women, and that the medical consequences of omission, especially frequent omission, may be severe. Although a strong association between omission and disordered eating was observed, these data suggest that this link may be complicated by important diabetes-specific factors. Patients preoccupied with eating and weight concerns may also become emotionally overwhelmed by diabetes and/or fearful of normoglycemia (and the associated weight-related consequences), thus reinforcing the desire to omit insulin and maintain elevated blood glucose levels.

Adolescent↗
PubMed1994

Propofol--contrasting effects in movement disorders.

We report two patients presenting for thalamotomy in whom tremor was abolished for 8 h after propofol anaesthesia. Propofol has two contrasting actions. It may have an anti-Parkinsonion effect, abolishing abnormal limb movements. On other occasions, propofol is known to induce spontaneous abnormal limb movements, as well as epileptiform activity. Propofol is probably best avoided for stereotactic procedures. It is difficult to reconcile these two opposing actions.

Anesthesia, Intravenous↗
PubMed1992

Correlates of hypoglycemic fear in type I and type II diabetes mellitus.

We examined whether fear of hypoglycemia in insulin-dependent diabetes mellitus was associated with (a) higher levels of trait anxiety and general fearfulness, (b) difficulty in differentiating symptoms of anxiety and hypoglycemia, and (c) past experience with hypoglycemia. Joslin Diabetes Center outpatients with Type I and Type II diabetes (N = 232), all requiring insulin, were surveyed. Type I patients experienced significantly more fear of hypoglycemia than Type II patients. For the Type I and Type II groups, higher scores on the Worry subscale of the Hypoglycemia Fear Survey (HFS-W) were associated with higher levels of trait anxiety and fear. Higher scores on the Behavior subscale (HFS-B) were associated with higher levels of fear. Among Type I subjects only, HFS-W scores were also positively associated with past hypoglycemic experience and with difficulty in differentiating anxiety and hypoglycemic symptoms. These latter relations remained significant even after the variance resulting from trait anxiety and fear was removed. Other significant associations with HFS-B scores were not observed.

Adaptation, Psychological↗
PubMed1992

Exercise and the brain: angiogenesis in the adult rat cerebellum after vigorous physical activity and motor skill learning.

This study compared the morphology of cerebellar cortex in adult female rats exposed for 1 month to repetitive exercise, motor learning, or an inactive condition. In the exercise conditions, rats that were run on a treadmill or housed with access to a running wheel had a shorter diffusion distance from blood vessels in the molecular layer of the paramedian lobule when compared to rats housed individually or rats that participated in a motor skill learning task. Rats taught complex motor skills substantially increased the volume of the molecular layer per Purkinje neuron and increased blood vessel number sufficiently to maintain the diffusion distance. These results dissociate angiogenesis associated with increased neuropil volume (as seen in the motor learning group) from angiogenesis associated with increased metabolic demands (as seen in the exercise groups). While the volume fraction of mitochondria did not differ among groups, the mitochondrial volume fraction per Purkinje cell was significantly increased in the motor skill rats. This appears to parallel the previously reported increase in synapses and associated neuropil volume change.

Animals↗
PubMed1992

Biomechanical aspects of a fluid percussion model of brain injury.

The fluid percussion model is in widespread use for the study of brain injury. However, the tissue deformation characteristics of the model have not been determined. Studies have suggested that at high levels of fluid percussion, the fluid percussion model is primarily a model of brainstem injury. It was proposed that this occurs as a direct result of the volume influx to the cranial vault at the moment of impact. This study examines the biomechanical deformation produced by the fluid percussion model. The purpose of this investigation was to describe the regional strain distribution in brain tissue at the moment of impact and to determine the effect of volume efflux produced by the percussion device. A cat skull was sectioned parasagittally and filled with an optically transparent gel. A grid pattern was painted in the midsagittal plane and was used to record the surrogate brain tissue deformation in response to fluid percussion loading. Motion of the grid pattern at low and high levels of fluid percussion loading was recorded using a high-speed camera, and a series of photographs developed from the high-speed film were analyzed to determine the intracranial strain distribution at these loading levels. The results of these studies indicated that the maximum site of strain was located in the region of the lower brainstem and that deformations were negligible in other regions of the brain. These studies provide an explanation for the pathophysiologic results obtained in a parallel series of experiments from which it was concluded that high-level fluid percussion is predominantly a model of lower brainstem injury.

Animals↗
PubMed1992

Hyperglycaemia, hypoglycaemia, and blood glucose control in diabetes: symptom perceptions and treatment strategies.

Recent research has suggested that patients with Type 1 diabetes who are in chronically poor blood glucose control perceive hyperglycaemia differently from those who are in good control. To extend these observations 181 insulin-treated patients with Type 1 or Type 2 diabetes were studied. Patients completed a self-report questionnaire which included items concerning feelings about high and low blood glucose levels and strategies for maintaining blood glucose control. Glycosylated haemoglobin levels were also measured. We hypothesized that level of blood glucose control would: (1) be associated with perceptions of hyperglycaemia and treatment strategies for managing hyperglycaemia and (2) not be associated with perceptions and strategies concerning hypoglycaemia. In comparison with those in 'acceptable' or 'poor' blood glucose control, those in 'good' control perceived symptoms of hyperglycaemia at lower blood glucose levels (p less than 0.001) and felt physically best at lower blood glucose levels (p less than 0.001). They, also began treatment for hyperglycaemia at lower glucose levels (p less than 0.05), set lower minimal (p less than 0.001) and maximal (p less than 0.001) glucose levels as treatment goals, and tested their blood glucose levels more frequently (p less than 0.05). Among Type 1 diabetic patients, those in 'good' control reported experiencing hypoglycaemia at lower glucose levels than those in 'acceptable' or 'poor' control (p less than 0.05). No differences in treatment strategies of hypoglycaemic symptoms were apparent. This study suggests an influence of patients' perceptions of symptoms and treatment in self-care of diabetes.

Adult↗