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F Wald

Publications and source records attributed to F Wald.

10 recordsLinked to original sources
PubMed2000

Comparison of the safety of drug delivery via HFA- and CFC-metered dose inhalers in CAO.

The objective of this study was to compare the long-term safety of a fixed combination of fenoterol hydrobromide (50 microg) and ipratropium bromide (20 microg) delivered using a metered dose inhaler (MDI) formulated with a non-chlorinated propellant, hydrofluoroalkanel34a (HFA-MDI), with delivery using the conventional chlorofluorocarbon propellant (CFC-MDI, Berodual/Bronchodual). The study was designed according to Safety Assessment of Marketed Medicines (SAMM) guidelines, to reflect as far as possible the use of MDls under normal prescribing conditions. Two thousand and twenty-seven patients with chronic airways obstruction (CAO) were enrolled from 99 centres in France, 95 centres in Germany and 24 centres in Italy. Following a 2-week run-in period, patients were randomized on a 2:1 basis (1,348 patients to HFA-MDI, 679 patients to CFC-MDI) to receive a flexible dose regimen of the combination (2 puffs, 2-4 times a day, as prescribed by the investigator) during a 12-week open label phase. The overall incidence of adverse events was comparable between both groups. In addition, the incidence of respiratory side effects was also similar, with CAO exacerbations or bronchitis the most frequently recorded events. The safety profile of the HFA formulation was comparable to those of the marketed CFC-MDIs used in Germany and France/Italy. No clinically significant differences were detected between HFA134a or CFC driven inhalers on the switch from CFC- to HFA-MDI (2 weeks before randomisation versus 2 weeks after randomization). There was a trend for taste complaints to be reported more frequently by patients in the HFA-MDI group (0.7% before randomization versus 3.4% after randomization). This, however, was an expected finding as the HFA134a formulation does have a different taste to the CFC formulation. No difference between formulations was observed in the incidences of coughing or paradoxical bronchospasm. The incidence of falls in FEV1 >15% within 15 min following inhalation at each of the clinic visits was 1.2% for both CFC- and HFA-MDIs. In conclusion, administration of a fenoterol/ipratropium bromide combination via hydrofluoroalkane-metered dose inhaler is as safe as delivery by the currently available chlorofluorocarbon-metered dose inhaler, in an extended population of patients with CAO under normal prescribing conditions.

Administration, Inhalation↗
PubMed1976

Regulation of neuronal properties by afferent connections. I. Functional changes in snail neurons following section of presysnaptic nerve fibers.

The left cerebral connective of snail ganglia containing afferent inputs to a particular neuron was sectioned. One week after the operation synaptic potentials were not obtained when the connective was stimulated, and they had not reappeared after 60 days. The current-voltage relationship of denervated cells showed a rectification in the hyperpolarizing direction, whereas that of control cells had an ohmic behavior. Depolarization or conductance changes produced by ACh or carbachol showed a supersensitivity in denervated cells, evidenced by a shift to the left of the dose-response curve and an increase of the maximal responses obtained. The reversal potential of ACh shifted from--22 mV in the control to--8 mV in denervated cells. Depolarization produced by serotonin was similar in control and denervated cells.

Acetylcholine↗
PubMed1972

Ionic differences between somatic and axonal action potentials in snail giant neurones.

1. The ionic requirements of the somatic and axonal action potentials of ;H' neurones of the snail Cryptomphallus aspersa were studied using intracellular micro-electrodes.2. The overshoot of the somatic action potential increased by 10 mV for a tenfold increase in [Ca(2+)](o). In calcium-free media the action potential decreased gradually to values of 50 to 90% of the control and they could be completely eliminated with 2 mM-EGTA. The maximum rate of rise also varied with [Ca(2+)](o).3. After 2 hr in sodium-free solution the somatic action potential decreased 6% in overshoot and 24% in rate of rise.4. The somatic action potential was not affected by TTX, 5 x 10(-6) g/ml. Procaine, 18 mM, reduced its rate of rise but did not eliminate it whereas 30 mM-CoCl(2) did.5. The size of the axonal action potential increased with increased [Na(+)](o), but decreased with an increase in [Ca(2+)](o).6. Procaine, 18 mM, abolished the axonal action potential whereas it was not affected by TTX, 5 x 10(-6) g/ml., nor, usually, by 30 mM-CoCl(2).7. The results obtained by studying the compound action potential of the nerves were similar to those from axonal action potentials.8. The possibility that the somatic action potential is mainly calcium dependent while the axonal action potential is mainly produced by sodium is discussed.

Action Potentials↗
PubMedDate not supplied

Regulations vs. ideals: a case history of a hospice closure.

The cost of health care and health insurance and the increasing number of Americans without access to basic health services has become a primary issue in today's society. Leading politicians, economists, planners, and private individuals recognize the essential need to re-design the system and provide coverage to all Americans. However, the history of programs strangling in the red tape created by inflexible regulatory efforts to set standards, monitor performance, and control costs, thereby denying access to individuals they were specifically designed to serve, points to the need for an equally new approach to planning such a system. The authors have attempted to illustrate, through the case history of the closure of a hospice serving a poor socioeconomic area of New York City, the need for government regulators, program planners, and caregivers to recognize and define common goals and develop flexible and cooperative working relationships.

Facility Regulation and Control↗