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Biomedical subjects

C R Jenkins

Publications and source records attributed to C R Jenkins.

At least 19 recordsLinked to original sources
PubMed1998

Standardization of ambulatory peak flow monitoring: the importance of recent beta2-agonist inhalation.

Standardization of conditions for peak expiratory flow (PEF) monitoring is much more difficult in practice than for laboratory spirometry. Patients are usually asked to record PEF before medication. The aim of this study was to determine the effect of prior bronchodilator use on PEF outcome measures in a clinical trial. Electronic PEF records from 43 subjects with poorly controlled asthma were examined to determine the frequency with which beta2-agonist was inhaled <4 h before PEF measurement, as such PEF are potentially "postbronchodilator". The effect of inclusion of such PEF values on improvement in PEF outcome measures after 8 weeks of inhaled budesonide was calculated. Subjects were asked to record PEF before medication. During run-in, the median frequency of postbronchodilator PEF was 29%, falling to 0% after 8 weeks of budesonide. Inclusion of postbronchodilator PEF led to an overestimation of average morning, evening and daily PEF during run-in (p<0.001). Improvement in these indices with treatment was, therefore, underestimated. Minimum morning PEF expressed as per cent personal best was unaffected. Subjects may not be able to withhold beta2-agonist for 4 h before every peak flow reading. This may change as the level of asthma control changes, leading to a systematic bias in clinical trial end-points or inaccuracy in individual treatment decisions. Simple changes to peak expiratory flow instructions and analysis are proposed.

Administration, Inhalation↗
PubMed1998

Pitfalls in processing home electronic spirometric data in asthma.

Electronic spirometers offer the prospect of paperless home monitoring, but data quality is not automatically better than from conventional monitoring. The aim of this study was to determine the extent to which the quality and processing of self-recorded spirometric data from patients with asthma complied with international guidelines for spirometry. Data were from 33 subjects with poorly controlled asthma who had completed the first 9 weeks of a clinical budesonide trial. MicroMedical DiaryCard electronic spirometers were used to record three spirometric manoeuvres in twice-daily sessions. Confounding events were recorded in a paper diary. Within-session reproducibility was calculated for forced expiratory volume in one second (FEV1), forced vital capacity (FVC) and peak expiratory flow (PEF) during the first week of run-in and week 9 of budesonide treatment. Geometric means of within-session reproducibility (mean difference between highest and second-highest value from each session over a one-week period) for FEV1, FVC and PEF were 76 mL, 116 mL and 18 L x min(-1), respectively, during run-in. Times of spirometric sessions varied widely, with some overlap between morning and evening session times. Manoeuvre-induced falls in PEF and FEV1 occurred only as often as expected by chance. Nonasthma events including equipment faults and painful conditions caused changes in spirometric results. Home spirometric monitoring can be carried out with excellent reproducibility in patients with asthma. However, quality-control issues are complex and an accompanying paper diary remains essential.

Adolescent↗
PubMed1997

Ultrastructural pathology and cytochemical investigations of L-2-chloropropionic acid-induced neurointoxication of the rat cerebellum.

The objectives of the studies described were to assess the ultrastructural neuropathology, blood-brain barrier (BBB) integrity and calcium status of the cerebellum of rats following a single dose of 750 mg.kg-1 L-2-chloropropionic acid (L-2-CPA). The first indications of intoxication appeared at 36 h when condensation of many granule cells associated with Purkinje cell degeneration and marked astroglial swelling were observed. Some electron-lucent granule cells were also noted lying amongst these condensed forms. Condensed granule cells had swollen, electron-lucent mitochondria, dilated Golgi apparatus and nuclear crenation. Occasionally, areas of the granule cell necrosis were also present at this time. Granule cell condensation probably represents a preliminary and irreversible stage in an excitotoxic process that leads to necrosis. At 48 and 72 h, most granule cells were necrotic, and occasionally, extravasation of both erythrocytes and leucocytes into the expanded extravascular space was observed. Evaluation of the BBB by ultrastructural cytochemical visualisation of horseradish peroxidase injected i.v. 2 min before killing by perfusion fixation showed substantial leakage. At 36 h post-dose, ultrastructural calcium localisation using oxalate/pyroantimonate precipitation demonstrated a substantial increase in calcium pyroantimonate precipitate in mitochondria and other membranous cytoplasmic organelles (especially the Golgi apparatus) in condensed granule cells, but with little in their nuclei. However, their immediate neighbours (of ostensibly normal ultrastructural appearances) contained greater amounts of intranuclear precipitate. Swollen astroglial cells (especially the Bergmann glia) contained considerable quantities of precipitate. A possible excitotoxic mechanism via L-2-CPA-induced NMDA receptor agonism leading to overwhelming calcium influx and disruption of cellular calcium homeostasis is proposed.

Animals↗
PubMed1997

Riga-Fedes syndrome: natal or neonatal teeth associated with tongue ulceration. Case report.

A case of natal teeth associated with traumatic ulceration to the ventral surface of the tongue (Riga-Fedes syndrome) in a four week old boy is presented. On radiographic examination, two teeth, present at birth, were found to be early erupted deciduous lower central incisors. A family history of natal teeth, all involving both lower deciduous central incisors associated with trauma to the tongue during suckling, was elicited. The ulceration healed over a period of four weeks using an innovative conservative treatment regime, involving the use of Stomahesive Wafer. Four months later the only sign of any previous pathosis was a fibrous scar on the ventral surface of the tongue.

Bandages↗
PubMed1994

Acute effect of sodium cromoglycate on airway narrowing induced by 4.5 percent saline aerosol. Outcome before and during treatment with aerosol corticosteroids in patients with asthma.

STUDY OBJECTIVE: To investigate the acute effect of sodium cromoglycate on airway responses to 4.5 percent saline aerosol challenge, before and during treatment with inhaled budesonide--a corticosteroid. DESIGN: Open study, with a total of five visits, two before budesonide treatment, and three follow-up visits, two between 5 and 6 weeks and one at more than 11 weeks. SETTING: Referral-based Respiratory Investigation Unit at Royal Prince Alfred Hospital, a major Sydney-based teaching hospital. PATIENTS: Eleven patients with asthma (ten atopic), with a PD20 FEV1 to 4.5 percent saline aerosol challenge and about to commence inhaled budesonide for treatment of their asthma. INTERVENTIONS: The 40 mg of sodium cromoglycate was inhaled before a 4.5 percent NaCl challenge, both before and after regular (36 +/- 9 d) treatment with budesonide (1,000 micrograms/d). The final challenge was repeated in ten subjects after 11 weeks or more of treatment with budesonide. MEASUREMENTS AND RESULTS: Sensitivity to 4.5 percent saline aerosol was measured as the dose of saline aerosol required to induce a 20 percent fall in FEV1 (PD20). Reactivity was measured as the dose-response slope by taking the percent fall in FEV1 and dividing it by the dose required to induce the fall. On the control day the geometric mean PD20 (95 percent CI) for 4.5 percent saline aerosol was 2.8 (1.4 to 5.4) and the dose response slope (DRS) 5.6 (2.9-11.1). An acute dose of sodium cromoglycate reduced sensitivity (PD20) by 8-fold and reactivity (DRS) 12.3-fold. This effect was similar in magnitude to that measured after regular treatment with budesonide alone. When sodium cromoglycate was given during treatment with budesonide, the PD20 was reduced 16-fold and the DRS 42-fold, and this was greater than the reduction with budesonide taken for 3 months (p < 0.03, p < 0.05 respectively). CONCLUSIONS: Sodium cromoglycate inhibits responses to 4.5 percent saline aerosol and has additional benefits to those conferred by aerosol steroids. The mechanism for responsiveness to saline aerosol and efficacy of these drugs may relate to alteration in chloride ion channel regulation by inflammation.

Adolescent↗
PubMed1990

Assessment of bronchial responsiveness as a guide to prognosis and therapy in asthma.

The severity of airway inflammation in patients with asthma is best assessed by combining several tests of bronchial responsiveness. The prognostic significance of bronchial responsiveness is unknown, but indirect evidence suggests that those with moderate and severe asthma rarely remit spontaneously and permanently. Assessment of severity is crucial to the rational management of all patients with asthma. Severity can be used as a guide to both short- and long-term management.

Asthma↗
PubMed1988

Effect of prednisone and beclomethasone dipropionate on airway responsiveness in asthma: a comparative study.

To examine the effect of corticosteroids on bronchial hyperresponsiveness, a randomised, double dummy, single blind crossover study was performed in 18 subjects with chronic asthma, comparing the effect of three weeks' treatment with inhaled beclomethasone dipropionate, 1200 micrograms daily, and oral prednisone 12.5 mg daily. The 12 week study began with a three week run in period of baseline treatment, which was continued unchanged throughout the study, and the two treatment periods were separated by a three week washout period. Patients kept daily Airflometer readings and attended the laboratory every three weeks for spirometry and a histamine inhalation test for determining the provocative dose of histamine causing a 20% fall in FEV1 (PD20). The mean FEV1 at the start was 1.9 litres (56% predicted). There was no significant change in PD20 with prednisone treatment, the mean PD20 being 0.56 and 0.59 mumol before and after treatment. There was, however, a significant improvement in PD20 with beclomethasone dipropionate treatment, the geometric mean PD20 being 0.38 and 1.01 mumol before and after treatment (p less than 0.001). There was a small but significant improvement in mean FEV1 after beclomethasone dipropionate treatment--from 1.9 to 2.2 litres--but no change after prednisone. Both medications produced significant and similar improvements in morning and evening Airflometer readings, post-bronchodilator improvement, and diurnal variation. Thus at doses that had similar beneficial effects on lung function beclomethasone dipropionate caused a significant improvement in bronchial hyperresponsiveness whereas prednisone caused no change. The superior topical anti-inflammatory effect of beclomethasone dipropionate may account for the different effects on bronchial hyperresponsiveness.

Administration, Inhalation↗
PubMed1984

Experience with allergic bronchopulmonary aspergillosis: some unusual features.

The clinical and immunologic features of ten patients with allergic bronchopulmonary aspergillosis (ABPA), observed over periods varying from 12 months to 10 years, are reported. Acute attacks of ABPA were characterized by several, or all of: increased cough and sputum, haemoptysis, pleuritic pain, expectoration of sputum plugs, and increasing airways obstruction. Peripheral blood eosinophilia and acutely elevated serum IgE levels were seen in all patients during acute attacks, sputum eosinophilia and recovery of Aspergillus in sputum was less common. However, blood eosinophilia was not present in all attacks of ABPA and sputum eosinophilia varied similarly from one attack to another. Six patients with previously documented multiple precipitin lines have had no demonstrable precipitins to Aspergillus on several occasions between attacks, three of these patients have also been negative during attacks. Five of the six patients have again developed positive precipitin lines. The total number of episodes in these ten patients was fifty two, three patients have had more than nine acute attacks of ABPA. There is no seasonal variation in this group of patients. Since diagnosis, only three patients have had an attack-free interval longer than 12 months. Two patients are steroid-dependent because of severe asthma, and nine have symptoms of bronchiectasis.

Adult↗
PubMed1984

Upper respiratory tract infections and airway reactivity in normal and asthmatic subjects.

To assess the effect of an upper respiratory tract infection (URTI) on airway reactivity, histamine inhalation tests (HITs) were performed prospectively in 44 nonsmoking asthmatic (14) and nonasthmatic (30) volunteers. Fifteen of the subjects developed an URTI during the following 4 months. Pulmonary function-forced expiratory volume in one second (FEV1), maximal midexpiratory flow rates (MMEFR) and maximal flow at 50% vital capacity (V50), and HITs, were studied at onset and 2, 3, and 4 wk after infection. There were no significant changes in pulmonary function during the total study period. For the 15 subjects, the mean provocative concentration of histamine causing a 20% fall in FEV1, (PC20H) was 8.73 mg/ml prior to onset of URTI, and at 1, 2, 3, and 4 wk after URTI was 7.97, 8.68, 8.13, and 8.61 mg/ml. These were not significantly different for the group as a whole, nor for the subgroups of asthmatics and nonasthmatics. Small changes in PC20H outside the normal range of variability occurred in 5 of 15 subjects. These were short-lived and no predictive factor for change in PC20H was identified in this group. Thus, URTI was not associated with significant changes in PC20H in this group of asthmatic and nonasthmatic subjects.

Adult↗
PubMed1983

Study of serum levels, venous irritation and gastrointestinal side-effects with intravenous erythromycin lactobionate in patients with bronchopulmonary infection.

Sixteen patients with bronchopulmonary infection received 500 mg erythromycin lactobionate by intravenous infusion every 8 h for 2 days. The duration of infusion was either 30 (8 patients) or 60 min (8 patients). An inline filterset (0.22 micrometer) was included in the intravenous administration set in 4 patients of each infusion group. Serum erythromycin levels were obtained before and at various times for 8 h after the first and fourth doses and before and immediately after the other doses. The incidence and severity of venous irritation and gastrointestinal side-effects were assessed. Mean (S.D.) peak erythromycin levels for the 30 min infusion were 26.31 (6.89) micrograms/ml (first dose) and 26.85 (6.11) micrograms/ml (fourth dose) and for the 60 min infusions, 23.96 (7.91) micrograms/ml (first dose) and 23.65 (6.55) micrograms/ml (fourth dose). Venous irritation was experienced by 12 patients, ranging from localized discomfort to thrombophlebitis, but the severity was significantly reduced by inline filtration (P less than 0.005). Gastrointestinal side-effects were reported by 8 patients and 1 patient withdrew because of severe abdominal pain and nausea. These symptoms were usually relieved by spasmolytic agents and possibly could be explained by high concentrations reaching the gut wall either by biliary excretion or direct transport from blood and stimulating smooth muscle motility.

Aged↗
PubMed1982

Ipratropium bromide and fenoterol by aerosolized solution.

Ipratropium bromide (0.5 mg) and fenoterol (2 mg) produced equivalent peak bronchodilatation between 1 and 2 h after administration to eight patients with chronic partially reversible airways obstruction. The duration of action compared with saline was 6 h for ipratropium and 4 h for fenoterol. Both drugs in combination produced greater bronchodilatation than either drug alone. The increase in FVC was disproportionately greater than FEV1 with both drugs and saline, suggesting relief of obstruction of small airways.

Aerosols↗
PubMed1982

Intramuscular administration of 15-methyl prostaglandin F2alpha in mid-trimester termination of pregnancy.

15-methyl prostaglandin F2 alpha was administered by intramuscular injection to thirty patients to terminate pregnancy in the mid-trimester. Termination was considered successful if this occurred within 24 hours and this was so in twenty-seven cases (90%). There were no serious complications. prochlorperazine mesylate and diphenoxylate hydrochloride reduced the incidence and severity of vomiting and diarrhoea.

Abortifacient Agents↗
PubMed1981

The metabolic actions of intravenous salbutamol and aminophylline singly and in combination.

1 The following four treatments were administered by constant intravenous infusion of four healthy volunteers in a balanced randomized study: 1) saline (30 min), salbutamol (0.15 micrograms kg-1 min-1 for 30 min) (sS), 2) saline, aminophylline (0.2 mg kg-1 min-1 for 30 min) (sA), 3) salbutamol, salbutamol (SS) and 4) aminophylline, salbutamol (AS). 2 Heart rate was recorded and venous blood taken for estimation of insulin, glucose, potassium and theophylline before and during the infusions (10, 20, 30, 40, 50 and 60 min). 3 The mean, peak heart rate increases from control, baseline values were 23.0 (sS), 3.5 (sA), 28.5 (SS) and 28.0 (AS) beats/min, the mean, peak insulin increases, 34.0 (sS), 0.5 (sA), 39.0 (SS) and 57.5 (AS) microU ml-1, the mean, peak glucose increases, 1.4 (sS), 0.1 (sA), 2.6 (SS) and 2.0 (AS) mmol 1(-1) and the mean, peak potassium changes, -0.45 (sS), 0.58 (sA), -0.78 (SS) and -0.68 (AS) mmol 1(-1). 4 The mean, peak serum theophylline levels were 48.1 mumol 1(-1) at 60 min in sA and 52.6 mumol 1(-1) at 50 min in AS (39.1 mumol 1(-1) at 30 min). 5 Salbutamol stimulated significant insulin release and produced hypokalaemia and glycogenolysis, whereas aminophylline induced no metabolic effect. 6 A comparison of sS and AS indicated a trend for aminophylline to potentiate the metabolic effects of salbutamol.

Adult↗