The effects of static charge in spacer devices on glucocorticosteroid aerosol deposition in asthmatic patients

Electrostatic charge in plastic spacer devices has been shown in vitro to reduce delivery of asthma medications intended for inhalation, but the effect of static charge on in vivo drug deposition is unknown. A six-way randomized crossover study was conducted in 10 mild asthmatic patients. Two plastic spacers (Nebuhaler and Volumatic) and one metal spacer (Nebuchamber) were tested. The spacers were used either "primed" or "unprimed". Priming was performed by firing 20 doses of placebo aerosol into a new spacer, hence coating the inner surface with surfactant and minimizing static charge. Unprimed spacers were new and were not treated. Pressurized aerosol canisters delivering budesonide (200 microg Pulmicort) were radiolabelled with the radionuclide 99mTc and lung deposition was measured by gamma scintigraphy. The radiolabel was shown to be a valid marker for the drug substance prior to the clinical phase of the study. Priming significantly increased mean whole lung deposition following inhalation from plastic spacers (Nebuhaler primed 37.7% and unprimed 26.7%, p=0.01; Volumatic primed 32.0% and unprimed 22.1%, p=0.02). Priming had no effect on the mean whole lung deposition following inhalation from the Nebuchamber (primed 33.5% and unprimed 32.9%). Lung deposition in vivo from plastic spacer devices will vary according to the electrostatic charge on the spacer walls. Priming reduces retention of drug on plastic spacer devices and increases lung deposition. Metal spacers are not susceptible to static charge, which should result in more predictable lung deposition.

The effects of static charge in spacer devices on glucocorticosteroid aerosol deposition in asthmatic patients

Electrostatic charge in plastic spacer devices has been shown in vitro to reduce delivery of asthma medications intended for inhalation, but the effect of static charge on in vivo drug deposition is unknown. A six-way randomized crossover study was conducted in 10 mild asthmatic patients. Two plastic spacers (Nebuhaler and Volumatic) and one metal spacer (Nebuchamber) were tested. The spacers were used either "primed" or "unprimed". Priming was performed by firing 20 doses of placebo aerosol into a new spacer, hence coating the inner surface with surfactant and minimizing static charge. Unprimed spacers were new and were not treated. Pressurized aerosol canisters delivering budesonide (200 microg Pulmicort) were radiolabelled with the radionuclide 99mTc and lung deposition was measured by gamma scintigraphy. The radiolabel was shown to be a valid marker for the drug substance prior to the clinical phase of the study. Priming significantly increased mean whole lung deposition following inhalation from plastic spacers (Nebuhaler primed 37.7% and unprimed 26.7%, p=0.01; Volumatic primed 32.0% and unprimed 22.1%, p=0.02). Priming had no effect on the mean whole lung deposition following inhalation from the Nebuchamber (primed 33.5% and unprimed 32.9%). Lung deposition in vivo from plastic spacer devices will vary according to the electrostatic charge on the spacer walls. Priming reduces retention of drug on plastic spacer devices and increases lung deposition. Metal spacers are not susceptible to static charge, which should result in more predictable lung deposition.

Scintigraphic assessment of drug delivery from the Ultrahaler dry powder inhaler

A new dry powder inhaler, the Ultrahaler, has been developed to deliver nedocromil sodium for the prophylaxis of asthma. This study was performed to compare the lung deposition of nedocromil sodium inhaled from the Ultrahaler at two different inhaled flow rates with that from a pressurised metered dose inhaler (MDI). A scintigraphic study was conducted in 12 healthy volunteers. On each study day, volunteers received a single 4.2 mg dose of nedocromil sodium from the Ultrahaler, using either an optimal (fast) inhaled flow rate or a suboptimal (slow) inhaled flow rate, or two doses of 2 mg nedocromil sodium from an MDI using an optimal (slow) inhaled flow rate. Used optimally, the Ultrahaler deposited significantly more (p < 0.05) of the metered dose in the lungs than either the Ultrahaler used suboptimally or the MDI used optimally [mean (SD) lung deposition values of 13.3 (4.8)%, 9.8 (3.5)%, and 7.5 (2.9)%, respectively]. Oropharyngeal deposition averaged over 80% of the dose for all three treatment regimens. This scintigraphic study demonstrated in vivo proof of concept for the Ultrahaler dry powder inhaler, and provided quantitative data on the relationship in lung deposition between the Ultrahaler and MDI which differed from that predicted by the in vitro fine particle fraction.

Proton MRS and quantitative MRI assessment of the short term neurological response to antiretroviral therapy in AIDS

OBJECTIVE

To investigate MRI and proton spectroscopy changes in five patients with HIV associated dementia complex (HADC) treated with antiretroviral therapy.

METHODS

Three markers were evaluated: (1) CSF/intracranial volume ratio; (2) T2 weighted signal ratio between parieto-occipital white and subcortical grey matter; and (3) metabolite ratios from long echo time (TE=135 ms) single voxel proton spectra of parieto-occipital white matter.

RESULTS

Spectroscopic changes indicated initial increases in N-acetyl/(N-acetyl + choline + creatine) ratio (NA/(NA+ Cho+Cr)) and progression of atrophy after initiation of antiretroviral therapy in four of five patients. When the neurological status of the patients subsequently deteriorated (two of five patients), the NA/(NA+Cho+Cr) ratio also declined.

CONCLUSIONS

Spectroscopic changes mirror reversible neuronal dysfunction. These objective, non-invasive techniques may be used for monitoring the neurological effects of antiretroviral drug therapy in patients with HADC.

Incidence and patterns of depression following coronary artery bypass graft surgery

A number of studies have examined the impact of coronary artery bypass graft surgery (CABG) on mood by means of cross-sectional analyses. These studies have provided a "snapshot" view of the numbers of patients showing psychological disturbance. To examine both the incidence and patterns of depression, 121 patients undergoing routine elective CABG were assessed preoperatively and postoperatively at 8 days, 8 weeks, and 12 months on the Beck Depression Inventory (BDI). The incidence findings suggested a small, transient increase in the number of patients with depression shortly after surgery. The preoperative score on the BDI was the best predictor of postoperative depression at all times of measurement. Discriminant function analysis on the patterns of depression indicated that trait anxiety maximally separated those patients who were depressed pre- and postoperatively from those only depressed shortly after the operation. The findings emphasize the value of examining patients' levels of anxiety and depression prior to surgery.

Spreading and retention of vaginal formulations in post-menopausal women as assessed by gamma scintigraphy

PURPOSE

In this paper we report on the first scintigraphic evaluation of vaginal dosage forms in post-menopausal women. To date, almost nothing is known about the in vivo performance of pharmaceutical formulations in the human vagina, which is a major deficiency in the rational design of drug delivery systems for both existing and new indications.

METHODS

The vaginal spreading and clearance of a radiolabelled pessary formulation and Replens (polycarbophil) gel, was assessed in six healthy, post-menopausal female volunteers over a six hour period using the technique of gamma scintigraphy.

RESULTS

In five out of the six subjects studied, clearance of the two formulations exhibited very little intra-subject variation. However, there was considerable inter-subject variability in clearance; in Subject 5 circa 80% of the products were retained whilst in Subject 2 less than 2% was present at the end of the six hour imaging period. Importantly, there was no evidence to suggest that either of the formulations dispersed material beyond the cervix, into the uterus, in any of the subjects studied.

CONCLUSIONS

The lack of significant retention of these products in most of the volunteers has obvious implications for the delivery of therapeutic agents. This study shows that gamma scintigraphy is an invaluable technique with which to assess novel formulations aimed at optimising retention in the vagina for topical or systemic drug delivery.

Anxiety and depression in adolescent cancer: findings in patients and parents at the time of diagnosis

Adolescent cancer is uncommon and presents an exceptional stress for the young patient and their parents. The emotional needs of adolescents with cancer are a major factor in the recommendation for the establishment of adolescent cancer units in major cancer centres in the U.K. However, there have been no prospective, longitudinal studies assessing the psychological impact of a diagnosis of cancer on the adolescent patient and their family. In 1994 we began a longitudinal study of the emotional impact of the diagnosis of cancer in patients and their families presenting to an adolescent cancer unit and of the coping strategies they employ. This first report presents the results of the study at the time of diagnosis in 42 adolescents, 34 mothers and 27 fathers. The Beck Depression Inventory (BDI) was used to assess depression and anxiety levels were measured using Spielberger's State Trait Anxiety Inventory (STAI). Adolescents and their parents completed the questionnaires on first admission to the adolescent cancer unit. The median time since cancer diagnosis was approximately 3 weeks. To provide normative data for the U.K. adolescent population, control values were obtained from 173 pupils of the same age and background. The results showed that, contrary to expectation, adolescents with cancer were no more anxious or depressed than the control adolescent population. Nevertheless, a substantial minority of patients and controls had elevated anxiety or depression scores. Girls were significantly more anxious (P = 0.011) and depressed (P < 0.0001) than boys. Mothers were the most anxious family members and were significantly more anxious than fathers (P = 0.038). Parental anxiety scores, especially mothers, were much higher than reported norms. There was no significant difference between mothers' and fathers' depression scores. Although at the time of diagnosis adolescent cancer patients are not more anxious or depressed than their healthy peers, many adolescents without cancer are anxious or depressed. Staff on adolescent cancer units should therefore be aware of the frequency of emotional disturbance in this population. Mothers are the most anxious family members. Although the findings are relatively reassuring at the time of diagnosis, follow-up data from this cohort will show whether anxiety and depression change with treatment involving intensive chemotherapy, surgery and radiotherapy and will indicate the coping strategies which patients and their families adopt in dealing with both the disease and its treatment.

Psychosocial measures in musculoskeletal trials

Measurement of psychological and social factors in studies of musculoskeletal disorders has become increasingly important with the need to show an effect of interventions on individuals' lives. Because information of psychological states involves patients reporting their private sensations, specific issues of their assessment need to be considered. Two of these issues are the problem of what constitutes the gold standard and the interpretation of causal direction of effects. The role of psychosocial factors in the assessment of disability is often ignored and frequently the distinction between disability and handicap confused. I describe and discuss the different measures commonly used to assess disability in arthritis. The assessment of symptoms, such as pain, stiffness, and fatigue are considered, as well as the examination of psychological well being. Interactions between these factors are also discussed. A number of other psychological variables have been developed and found to play a mediating role between the illness and its effect. These include coping, social support and other health cognitions, such as perceptions of control. The important role of psychosocial factors and their effect on measures on symptoms and disability suggest that need for more detailed examination of factors associated with outcome, and also the need to consider more complex designs that control for some of these factors at the outset of studies.

Cerebral proton magnetic resonance spectroscopy in asymptomatic HIV infection

OBJECTIVE

To determine whether proton magnetic resonance spectroscopy (MRS) demonstrates central nervous system abnormalities in asymptomatic HIV-1-infected individuals.

DESIGN

Both prospective and retrospective cross-sectional analyses of MRS in asymptomatic HIV-infected individuals.

SETTING

Two specialists HIV/AIDS outpatient facilities in London.

PARTICIPANTS

Eighty-four HIV-1 seropositive asymptomatic men; 29 HIV-1 antibody-negative homosexual men at high-risk for HIV infection and 48 HIV-1 antibody-negative men at low-risk for HIV infection as controls.

MAIN OUTCOME MEASURES

Single voxel, gradient-localized proton MRS performed at 1.5 T with 135 msec echo-time and 1,600 msec repeat-time in an 8 ml volume of interest positioned in the parieto-occipital white matter. Spectroscopic results were expressed as ratios between the areas under the N-acetyl (NA), creatine (Cr) and choline (Cho) resonance peaks.

RESULTS

There were no differences between those controls at high and those at low-risk for HIV infection. Comparing the combined control groups with the asymptomatic seropositive patients there were statistically significant differences in NA/Cho, NA/Cr (both P < 0.05) and NA/(NA + Cho + Cr) (P < 0.01).

CONCLUSION

Abnormalities in cerebral biochemistry may be demonstrated by proton MRS during asymptomatic HIV-1 infection.

Effect of add-on devices for aerosol drug delivery: deposition studies and clinical aspects

Add-on devices for pressurised metered dose inhalers (MDIs) improve "targeting" of drug to the lungs and can correct for hand-breath dyscoordination. Measurements of drug delivery from add-on devices by gamma scintigraphy have shown that compared to an MDI, oropharyngeal deposition is always reduced, and that lung deposition is generally either increased or unchanged. The total body dose may be reduced by over 80%. Increases in lung deposition may not result in improved bronchodilator response if the top of the dose-response curve has been reached. Add-on devices with one-way valves and mouthpiece or mask may enable asthma to be controlled with a smaller delivered dose of drug than from an MDI, and have proved to be viable lower cost alternatives to the use of nebulizers for delivering high dose bronchodilators to patients with severe acute asthma, and steroids to chronic asthmatics.

Magnetic resonance imaging of the brain and cerebral proton spectroscopy in patients with systemic lupus erythematosus

OBJECTIVE

To investigate the prevalence and extent of cerebral changes in patients with systemic lupus erythematosus (SLE) by magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS).

METHODS

SLE patients (47 women) and controls (25 women) underwent 1.5T MRI. A semiautomated segmentation technique calculated cerebrospinal fluid (CSF) and brain volumes. Proton MRS of the frontal and parieto-occipital white matter yielded metabolite ratios of N-acetyl groups (NA), choline, and creatine.

RESULTS

Compared with the control group, the SLE patients more often had cerebral atrophy on MRI (32% versus 0%), confirmed by an increase in the CSF to intracranial volume ratio. The patients also had old infarcts and hemorrhages (8.5% versus 0%) and more small white matter lesions (23% versus 8% had > 5 such lesions). MRS showed relative reduction of NA peaks. Although no patient was studied when acutely ill, prior neurologic involvement was related to abnormal findings.

CONCLUSION

MRI and MRS are helpful in the investigation of cerebral complications of SLE. There are chronic changes which may be ischemic in nature. Their precise cause, consequences, and prevention are current challenges.

Efficient delivery to the lungs of flunisolide aerosol from a new portable hand-held multidose nebulizer

In order to provide asthmatic patients with an inhaler that does not use chlorofluorocarbon propellants, a novel multidose hand-held nebulizer (RESPIMAT, Boehringer Ingelheim Ltd.) has been developed. This device delivers 200 x 15 microL metered doses of drug solution, but does not use propellants of any kind. In this study of 10 healthy volunteers, the deposition pattern in the lungs and oropharynx of an ethanolic solution of flunisolide delivered via a prototype III multidose nebulizer has been determined by gamma scintigraphy. A comparison was made with the same dose (250 micrograms) of flunisolide delivered by a pressurized metered dose inhaler (MDI) and MDI plus Inhacort spacer. Mean (SD) whole lung deposition from the multidose nebulizer (39.7 (9.9) % of the metered dose) was significantly higher than that from either MDI (15.3 (5.1) %, P < 0.01) or MDI plus spacer (28.0 (7.0) %, P = 0.01). A mean 10.4% of the dose was recovered from an exhaled air filter for the multidose nebulizer, but less than 2% of the dose for MDI or MDI plus spacer. Oropharyngeal deposition was significantly reduced for the multidose nebulizer (39.9 (9.4) %) compared to MDI (66.9 (7.1) %), but was reduced further for the MDI plus spacer (27.3 (11.3) %). The multidose nebulizer delivers an unusually high percentage of an aerosol dose to the lungs, and it "targets" flunisolide to the lungs more effectively than the MDI. The multidose nebulizer could constitute a viable alternative to MDIs in asthma maintenance therapy.

The concerted regulation of cPLA2, COX2, and lipocortin 1 expression by IL-1beta in A549 cells

The pro-inflammatory effects of IL-1beta have been linked to the induction of the enzyme COX-2. We now show that in addition to increasing the expression of COX-2, IL-1beta concomittantly decreased the expression of lipocortin 1 on the surface of A549 cells. Furthermore, cytosolic PLA2 is concomittantly activated by phosphorylation-resulting in a stimulation of arachidonic acid and PGE2 release. All of these effects appear to be mediated via a common pathway of PLC and PKC activation. Activation of cPLA2 is inhibited by dexamethasone in a lipocortin 1-dependent mechanism. We present a novel hypothesis whereby the effects of IL-1beta are not only due to activation of enzymes necessary for generation of eicosanoids but also to an inhibition of mechanisms that regulate the supply of arachidonic acid.

Characteristics of radiolabelled versus unlabelled inhaler formulations

The total and regional deposition patterns of aerosols released from pressurized metered dose inhalers (MDIs) may be determined by gamma scintigraphy. Owing to difficulties in chemically labelling drug molecules themselves, the formulation may be radiolabelled with a suitable gamma-ray-emitting radionuclide (usually 99mTc). Validation measurements must then be performed to check that the drug formulation has not been altered significantly by the radiolabelling process and that the radiolabel acts as an adequate marker for the drug across the full range of particle sizes. These radiolabelling techniques have proved widely applicable, not only to pressurized MDIs, but also to dry powder formulations.

Cerebral emboli and cognitive outcome after cardiac surgery

There have been major advancements in cardiac surgery over the past two decades, with a concomitant decrease in mortality and major morbidity. However, several recent studies have demonstrated that cardiac surgery poses significant risk for negative neurologic and neuropsychologic outcome. Although very few patients die as a result of cardiac surgery, more than two thirds of the patients demonstrate evidence of neuropsychologic dysfunction postoperatively. The mechanisms contributing to post-cardiopulmonary bypass neuropsychologic deficits are uncertain. However, two major interrelated etiologic factors, hypoperfusion and emboli, are suggested as probable culprits. It is important to define the relationship between these two putative mechanisms and postoperative neuropsychologic outcome in order to either prevent the problem or treat the effects of emboli or hypoperfusion. For example, if embolism is the cause of the deficits, increasing cerebral perfusion would deliver more emboli and increase the amount of severity of injury. Conversely, if hypoperfusion is the cause of the injury, then decreasing brain blood flow would increase the likelihood of injury. If both are important, their relative significance must be established, then one prevented and the effects of the other treated. This report discusses the methodology for detecting cerebral emboli during cardiac surgery. The incidence and severity of neuropsychologic deficits after cardiac surgery are discussed, as well as emboli in relation to composition and time of occurrence and their effect on neuropsychologic outcome.

Cerebral magnetic resonance relaxometry in HIV infection

A prospective, cross-sectional study was designed to determine the magnetic resonance relaxation times of cerebral white matter in human immunodeficiency virus (HIV) infected individuals. T1 and T2 were estimated at 1.5 T using four-point methods. Seventy-five HIV-1 seropositive subjects, 48 seronegative blood donors, and 17 seronegative homosexual men were studied. Associations between relaxometry and clinical classification, neurological status, immunological status, and qualitative MRI were investigated. Statistically significant differences in white matter T1 relaxation time were found comparing low-risk control and AIDS groups (p < .005), seropositive subjects with neurological signs and those without (p < .005), and subjects with low (CD4 < or = 200 x 10(6)/l) and high (CD4 > 200 x 10(6)/1) CD4 cell counts (p < .05). These findings add to the body of information that reveals no HIV-related change in the brain before the onset of symptomatic immunosuppression and go someway to validating the previous visually rated, qualitative findings. Statistically significant difference in white matter T2 relaxation time were also found comparing the two control groups (p < .005) highlighting the need for appropriate controls.

Toxoplasmosis and primary central nervous system lymphoma in HIV infection: diagnosis with MR spectroscopy

PURPOSE

To differentiate intracranial lymphoma from Toxoplasma gondii lesions in patients infected with the human immunodeficiency virus, by means of localized spin-echo proton magnetic resonance (MR) spectroscopy.

MATERIALS AND METHODS

Twenty-seven lesions were studied (18 T gondii lesions, nine lymphoma lesions) at 1.5 T. Spectra were acquired at an echo time of 135 msec from voxels centered on the lesions. Both visual analysis and spectral fitting were used to obtain metabolite ratios for choline (Cho), creatine (Cr), N-acetyl (NA), lactate, and lipids.

RESULTS

Three spectral categories were seen. One had large lipid peaks with suppression of other metabolites. Another had an elevated Cho/Cr ratio with relatively diminished NA. The third had features of the other two. Examples of each spectrum type were acquired from both T gondii and lymphoma lesions. Neither method of analysis allowed differentiation between lesion types. MR spectroscopy showed an overlap of spectra.

CONCLUSION

The authors conclude that toxoplasmosis and lymphoma cannot be differentiated with spin-echo proton MR spectroscopy at 135 msec.

Scintigraphic assessment of the oropharyngeal and nasal depositions of fusafungine from a pressurized inhaler and from a novel pump spray device

The distributions of fusafungine (Locabiotal, Servier) radiolabelled with 99mTc, and delivered either orally or intranasally, have been assessed in healthy volunteers from a pressurized metered-dose aerosol inhaler (125 micrograms per dose) and from a novel mechanical pump spray device (500 micrograms per dose). More than 90% of the dose was initially deposited in the oropharynx for oral dosing (n = 8), and more than 90% in the nose for nasal dosing (n = 9), with no significant penetration of aerosol into the lungs. Although not statistically significant, the mean area of deposition, measured in terms of gamma camera picture elements (pixels), was greater with the pump spray for both oral and nasal dosing. The area of deposition with the nasal pump spray extended into the turbinates in six of nine subjects, compared with only three of nine subjects for the pressurized aerosol. The data suggest that the distribution patterns of pump sprays and pressurized aerosols of fusafungine in the oropharynx and in the nasal passages are similar, and that the former can be substituted for the latter with little change in drug delivery.

A comparison of lung deposition patterns between different asthma inhalers

Drugs for the treatment and prophylaxis of asthma are delivered to the lungs by inhalation and this is facilitated by the use of pressurized metered dose inhalers (pMDIs), pMDIs with spacer devices and dry powder inhalers (DPIs). Lung deposition of drugs from pMDIs depends upon both the physicochemical nature of the aerosol formulation and the patient's inhalation technique, however, the majority of the dose from a pMDI is deposited in the oropharynx. Large volume spacer devices can reduce oropharyngeal deposition; however, lung deposition may be increased or decreased with a spacer in comparison with a pMDI, according to the design of the spacer, the aerosol formulation, the patient's inhalation technique and the extent to which the electrostatic charge on the spacer is controlled. Lung deposition of drug from DPIs also varies according to the design of the device. One DPI, Turbuhaler, deposits twice as much drug in the lungs as a pMDI, has a lower intersubject variability of lung deposition and results in lower oropharyngeal deposition.

Differences in aerodynamic particle size distributions of innovator and generic beclomethasone dipropionate aerosols used with and without a large volume spacer

BACKGROUND

The equivalence of generic beclomethasone dipropionate (BDP) formulations with their innovator counterpart must be demonstrated if generic formulations are to be used. This study has examined the aerodynamic particle size distributions of both innovator and generic formulations of BDP and the effect of a large volume spacer (Volumatic) on these distributions.

METHODS

Aerosol clouds of three formulations of BDP delivering 250 micrograms per metered dose were characterised using a high precision multistage liquid impinger, and the amount of drug in different particle size bands was determined by spectrophotometric assay.

RESULTS

The mean (SD) respirable fractions of Becloforte, Beclazone, and Filair without the spacer (n = 10) were 24.1 (2.1)%, 23.1 (2.7)%, and 23.0 (2.1)% respectively; however, the ratio of deposition on stage 4 of the impinger to that on stage 3 was lower for Beclazone and for Filair than for Becloforte, implying a smaller proportion of fine particles for the generic products. When the three products delivered via the Volumatic spacer device were compared, the respirable fraction for Becloforte (n = 10) was 25.0 (4.0)%, but those of Beclazone (n = 10) and Filair (n = 11) were 16.0 (1.9)% and 14.6 (3.4)%. Repeat testing (n = 5) at a later date showed higher mean respirable fractions for all three products, but a trend towards the highest respirable fraction for Becloforte, and the same rank order for the other two products.

CONCLUSIONS

These in vitro findings suggest that the particle size distributions of the two generic formulations of BDP are not equivalent to that of the innovator product. Some differences in particle size distributions might not have been detected by a twin impinger. Clinical testing would be required to assess the therapeutic equivalence of innovator and generic corticosteroid products used with or without spacer devices.

Factors associated with mood and mood disorders in SLE

This study examines the relative contribution of factors associated with anxious and depressed mood, and clinical anxiety and depression in SLE. Eighty sequentially consenting patients attending a rheumatology outpatient clinic were assessed on measures of anxiety and depression; disease activity; presence of autoantibodies; neuropsychological performance; and psychological and social factors. Mood and mood disorders were found to be unrelated to measures of disease activity but were found to be associated with psychological and social factors. These findings emphasise the importance of psychosocial factors in attempts to understand mood and psychological distress in SLE.