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Biomedical subjects

W J Becker

Publications and source records attributed to W J Becker.

At least 37 records · Page 2Linked to original sources
PubMed1999

Sumatriptan nasal spray: a dose-ranging study in the acute treatment of migraine.

This multicentre, randomized, double-blind, placebo-controlled, parallel group dose-ranging study compared the efficacy and tolerability of four doses of sumatriptan nasal spray (2.5, 5, 10 and 20 mg) with a placebo, in the acute treatment of a single migraine attack. In total, 544 patients received the study medication as a single spray in one nostril, to treat a single migraine attack in the clinic. Efficacy assessments included the measurement of headache severity, clinical disability, and the presence/absence of associated symptoms. The incidence of headache recurrence was also assessed. The three highest doses of sumatriptan (5 mg 49%, 10 mg 46%, 20 mg 64%) were significantly better than the placebo (25%) at providing headache relief (moderate or severe headache improving to mild or none) 120 min after treatment (P </= 0. 01). Also, the 20 mg dose was significantly superior to both the 10 and 5 mg doses at this time point (P < 0.05). The proportion of patients who were headache-free 120 min after treatment, was also higher following 20 mg (42%) rather than following any other sumatriptan dose (14-24%, P < 0.005 20 vs 10 mg) or placebo (11%). Headache recurrence in patients who had responded to initial treatment was reported by 30-41% of patients who received sumatriptan, compared with 33% of patients in the placebo group. Sumatriptan nasal spray was well tolerated, the incidence of adverse events with each dose of sumatriptan being similar to the placebo (20-27 and 23%, respectively). Apart from bad/bitter taste, the events were comparable with those reported following sumatriptan treatment by other routes of administration.

Adult↗
PubMed1999

Use of oral contraceptives in patients with migraine.

Migraine is most common in women in their childbearing years, the same population that also uses oral contraceptives (OCs). OC use can result in worsening, improvement, or no change in a woman's migraine. The pattern of the migraine attack may also change with, e.g., worsening of a pre-existing migraine aura. There is evidence that migraine with aura is a significant risk factor for ischemic stroke, with an odds ratio of approximately 6. Migraine without aura appears to result in much less increase in ischemic stroke risk, although it may still be significant. OCs, even those with an estrogen content of less than 50 microg, appear to cause an increase in ischemic stroke risk with an odds ratio of approximately 2, although the risk has been less in some studies. OC use in some patients with migraine with aura may lead to unacceptable ischemic stroke risk, because this results in the combination of two stroke risk factors. It is recommended that, when OCs are prescribed for patients with migraine, the potential risks and benefits be discussed with the patient and patients should be monitored for possible changes in their migraine. Caution should be exercised in OC use by women who have migraine with aura, especially older women and those who have other stroke risk factors. Pill use should be strongly discouraged in women who have a migraine aura beyond the ordinary or who develop new aura symptoms while taking OCs.

Contraceptives, Oral, Hormonal↗
PubMed1998

Episodic cluster headache in a community: clinical features and treatment.

OBJECTIVE: To study the clinical features and treatment given to episodic cluster headache patients in the Calgary region. PATIENTS: Fifty-one (51) patients who responded to a media campaign, had previously been diagnosed by their family physicians, and who met International Headache Society (IHS) criteria for episodic cluster headache, formed the population for this study. METHODS: The media campaign consisted of newspaper advertisements and radio publicity including physician interviews and talk shows. Patients were required to complete by 200-item questionnaire detailing clinical features and treatment of their cluster headache syndrome. Each patient was also interviewed by our research nurse for clarification and proper completion of questionnaire. RESULTS: Fifty-one percent (51%) of our patients had short headache attacks lasting one hour or less. Almost one-half (45%) had three or four attacks per 24 hour period. Eighty-six percent (86%) had been referred to a neurologist. Sixty-nine percent (69%) had never used oxygen, but of those who had, one-half were still using it. Sumatriptan by injection had been tried by 26% of patients and of these, 93% considered it effective. Subcutaneous dihydroergotamine had been tried by 8%. For prophylaxis, 41% had tried methysergide, 31% prednisone, and 4% verapamil. Many patients had been prescribed migraine prophylactic drugs which are ineffective for cluster headache, and some had also undergone dental procedures or nasal and sinus surgeries. CONCLUSIONS: Many cluster headache patients had not, to their knowledge, been prescribed or used the best symptomatic and prophylactic treatments for cluster headache. This should be addressed through educational programs and through making up-to-date information on the treatment of cluster headache readily available to physicians and patients.

Adaptation, Psychological↗
PubMed1997

Migraine and oral contraceptives.

Initiation of oral contraceptive (OC) therapy in migraine may worsen pre-existing migraine or change the pattern of the individual migraine attacks. Many women experience no change in their migraine and a few show improvement. Evidence is accumulating that migraine increases ischemic stroke risk and that this risk is higher in migraine with aura than in migraine without aura. OCs also increase stroke risk, and the increased stroke risk attributable to each of migraine and OC therapy may be additive. The risk of ischemic stroke in young women is very low and likely remains acceptably low in young women with migraine without aura and in those with a simple migraine aura when OCs are prescribed. However, the presence of a complex or prolonged migraine aura, or of additional stroke risk factors such as increased age, smoking, and hypertension likely increases the ischemic stroke risk further in patients with migraine when OCs are prescribed. Whether OCs can be prescribed safely for the patient with migraine depends upon many factors including patient age, type of migraine, and the presence or absence of other stroke risk factors.

Adult↗
PubMed1997

Effect of Chinook winds on the probability of migraine headache occurrence.

Our objective was to determine if Chinook weather conditions in the Calgary area increase the probability of headache attacks in migraine sufferers. Environment Canada meteorologic summaries for January through June 1992 were analyzed and times of Chinook wind onset identified. Chinook weather conditions were defined as calendar days when Chinook winds were present and the calendar day immediately preceding Chinook wind onset. The diaries of 13 migraine patients were analyzed, and times of headache onset classified according to the existing weather conditions. The probability of migraine headache onset was greater on days with Chinook weather (17.26%) than on non-Chinook days (14.65%) (P = 0.042). Older patients appeared more weather sensitive than younger patients. For patients over age 50, the probability of migraine occurrence on Chinook weather days was much greater than on non-Chinook days (P = 0.007). Chinook weather conditions increase the probability of migraine headache occurrence. Older migraine sufferers appear particularly vulnerable to this effect.

Adult↗
PubMed1997

Heterophilic antibodies produce spuriously elevated concentrations of the MB isoenzyme of creatine kinase in a selected patient population.

Dual-site murine antibody-based immunoassays are commonly used in clinical laboratories to quantitate the MB isoenzyme of creatine kinase (CK-MB). Because the serum level of CK-MB is a relatively specific and sensitive indicator of myocardial ischemic damage, accurate quantitation is essential for a correct diagnosis. Heterophile antibodies (eg, human anti-murine antibodies) can interfere with these assays, however, and produce erroneous results. A subpopulation of 19 surgical patients with colorectal carcinoma who had received injections of an 125I-labeled murine monoclonal antibody directed against a tumor-associated glycoprotein was studied. Serum specimens from eight patients (42%) showed a marked increase in the level of CK-MB and normal total CK concentrations. The increased concentrations of CK-MB, which were attributed to interference by human antimurine antibodies, were substantially reduced in these specimens after a heterophile blocking reagent was added. However, this reagent did not significantly alter the serum level of CK-MB in patients who had clinical evidence of acute myocardial ischemia.

Animals↗
PubMed1996

Impaired "natural reciprocal inhibition" in patients with spasticity due to incomplete spinal cord injury.

Experiments were performed to compare the ability of normal subjects and patients with spinal spasticity to suppress antagonist H reflexes during isometric ankle contractions. Soleus H reflex suppression was examined during tonic pretibial muscle contractions in which the torque levels were constant and during dynamic pretibial muscle contractions in which the torque followed a predetermined ramp. As well, subjects were instructed to alternately contract ankle plantarflexors and dorsiflexors at various frequencies to examine patterns of EMG activity during rhythmically alternating isometric contractions in antagonist muscles. Patients with incomplete spinal cord injury demonstrated reduced ability to suppress soleus H reflexes during pretibial muscle contraction. At slow speeds of alternating contraction, spinal cord injured patients retained the ability to perform alternating isometric pretibial/soleus muscle contractions. The patients demonstrated abnormal coactivation in soleus muscle during faster alternating isometric ankle muscle contractions. Furthermore, the patients who demonstrated the greatest impairment in natural reciprocal inhibition, also displayed the largest amount of coactivation. In general, the results would suggest that impairment of natural reciprocal inhibition is correlated with an increase in the amount of antagonist muscle coactivation seen during alternating isometric muscle contractions.

Adult↗
PubMed1996

Effectiveness of subcutaneous dihydroergotamine by home injection for migraine.

The effectiveness of dihydroergotamine administered by home subcutaneous injection by the patient or family for severe headache attacks was assessed retrospectively in 51 patients. Average follow-up was 21 weeks. Twenty-one patients had intermittent migraine attacks, 27 had transformed migraine with chronic daily headache, and 3 had chronic tension-type headache. Of the 51 patients taught home injection, 35% had an excellent overall response, 18% had a good response, 12% had a poor response but continued to use dihydroergotamine, and 35% had discontinued dihydroergotamine use. Side effects were the main reason for stopping dihydroergotamine. These included nausea or vomiting or both, limb pain or numbness or both, chest or throat tightness or both, and soreness at the injection site. Thirty-three patients (65%) continued to use dihydroergotamine at the end of the follow-up period. In patients who previously required injections from medical personnel for headache crises and in whom home injection of dihydroergotamine was effective, a dramatic reduction occurred in hospital emergency room and physician office utilization. Dihydroergotamine use by home injection can be an effective treatment for a significant proportion of patients with severe migraine including patients with transformed migraine and medication overuse.

Adult↗
PubMed1996

Alpha 1-antitrypsin deficiency: evaluation of bronchiectasis with CT.

PURPOSE: To assess bronchiectasis depicted with computed tomography (CT) in patients with alpha 1-antitrypsin deficiency and to examine associated clinical correlates. MATERIALS AND METHODS: CT scans in 14 patients with alpha 1-antitrypsin deficiency were evaluated by two thoracic radiologists for the presence and extent of bronchiectasis and emphysema. The findings were correlated with numeric infection scores on the basis of symptoms of sputum production and respiratory infection and with a history of conditions that may predispose to development of bronchiectasis. RESULTS: Six (43%) of 14 patients had CT evidence of bronchiectasis. Patients with bronchiectasis had significantly higher infection scores than did patients without bronchiectasis (P < .005). Two patients had diffuse cystic bronchiectasis, and neither reported a history of illness that may have predisposed them to this condition. CONCLUSION: Bronchiectasis may be more common in patients with alpha 1-antitrypsin deficiency than has been previously recognized. The diagnosis of alpha 1-antitrypsin deficiency should be considered in patients with emphysema and diffuse cystic bronchiectasis.

Bronchiectasis↗
PubMed1995

Long-term intrathecal baclofen therapy in patients with intractable spasticity.

BACKGROUND: Severe spasticity unresponsive to oral drugs may respond satisfactorily to baclofen delivered intrathecally. METHODS: Intrathecal baclofen (IB) therapy delivered by means of implanted infusion pumps was used for nine patients with severe spasticity. Six patients had multiple sclerosis, two cervical spinal cord injury, and one head injury. All were non-ambulatory. RESULTS: Patients showed improvement in many areas, including ability to transfer, seating, pain control, personal care, and liability to skin breakdown. Before IB therapy, only three of the nine patients were able to live at home in the community and six were institutionalized. At the end of our follow-up period, only one patient remained institutionalized, three lived in group homes and five lived at home in the community. In the year preceding pump implantation, the nine patients spent a total of 755 days in acute care hospitals. In the year following onset of IB therapy, they spent only 259 days in hospital. CONCLUSIONS: IB therapy can improve patient quality of life and can be cost-effective in carefully selected patients with severe spasticity and disability. The drug delivery catheter is that part of the therapeutic system most vulnerable to failure. Because of the varied expertise required to manage these patients effectively, and the potential for a variety of complications, it is essential that an IB program is supported by a well-organized multi-disciplinary medical team.

Adult↗
PubMed1995

Long term treatment of intractable reflex sympathetic dystrophy with intrathecal morphine.

BACKGROUND: Some patients with reflex sympathetic dystrophy (RD) develop intractable symptoms unresponsive to conventional therapy. Recently, intrathecal morphine therapy has been used with some success in such patients. METHODS: The clinical course of two patients with intractable reflex sympathetic dystrophy (RSD) is described. Both patients developed intractable leg pain, swelling and autonomic changes after a leg injury. Numerous medical treatments and surgical sympathectomies failed to provide long term relief. RESULTS: Relatively satisfactory symptom control was achieved only with the use of long term intrathecal morphine therapy delivered by subcutaneously implanted infusion pumps. Exacerbations of the RSD continued to occur, at times in association with further leg trauma, but these could be controlled by a temporary escalation of the intrathecal morphine dose. Complications of morphine therapy were relatively minor. A red rash appearing over the pump site was the first sign that a drug catheter break had occurred, necessitating surgical catheter revision. CONCLUSION: Long term intrathecal morphine therapy is a useful treatment option for patients with intractable severe RSD who have failed other therapies and remain markedly disabled.

Adolescent↗
PubMed1994

Cardiovascular responses to KC-135 hyper-gravity.

The present study was designed with two intentions; Are the effects of angular velocity detectable in the cardiovascular responses during the hyper-G? Another is object to examine how the otolith signal could modify the cardiovascular responses provoked by the exposure to the hyper-G. NASA/KC-135 hyper-gravity flight was used to generate high gravito-inertial forces to exclude a possible effect of angular velocity. Six healthy subjects was indicated to make dorsal flexion of the neck to reduce the otolith input. An exposure to +l.8Gz stress resulted in a remarkable increase of systolic and diastolic blood pressure, thereby pulse pressure became a little bit narrower. R-R interval revealed a tachycardia during the hyper-G except one subject. The present experiment bore the similar cardiovascular responses as those observed in the previous studies with a short rotating radius, suggesting that almost no effect of angular velocity acts on their responses. A weaker otolith input could possibly work on them. However a systematical observation can not recognize among the subjects for the vestibular effect on the cardiovascular responses. This fact of vestibular qualification leads us to speculate that it would depend on the subjects or other factors.

Adult↗
PubMed1992

Modulation of the soleus H-reflex during pedalling in normal humans and in patients with spinal spasticity.

Soleus H-reflexes were recorded in 10 normal subjects and seven patients with spasticity caused by incomplete spinal cord injury while they pedalled on a stationary bicycle which had been modified to trigger electrical stimuli to the tibial nerve at eight precise points in the pedal cycle. Stimulus strength was adjusted to yield M-waves of constant amplitude at each pedal position. During active pedalling, all normal subjects showed modulation of the H-reflex with the amplitude being increased during the downstroke portion of the pedal cycle and the reflex suppressed or absent during the upstroke. This modulation was not present during passive pedalling, with the experimenter cranking the pedals by hand, or when the pedals were locked at each of the eight positions. In five of the seven patients with spasticity, there was reduced or absent modulation of the H-reflex during active pedalling and the reflex remained large during pedal upstroke. It is concluded that descending motor commands that produce patterned voluntary activity during pedalling normally cause cyclical gating of spinal reflexes by either presynaptic or postsynaptic inhibitory mechanisms. Loss of supraspinal control over these spinal inhibitory systems could result in failure to produce appropriate suppression of reflexes during patterned voluntary movements such as pedalling or walking, and may be an important factor contributing to the functional disability in spasticity.

Adult↗
PubMed1991

Myoclonus and sensorimotor integration in a patient with Ramsay Hunt syndrome.

Clinical and neurophysiologic studies were done on a patient with action myoclonus secondary to Ramsay Hunt syndrome (dyssynergia cerebellaris myoclonica). Myoclonic jerks in the arms were much more common during movements directed to a target than in other movements. They appeared to be triggered primarily by external sensory inputs relevant to the movement rather than by the motor activity itself. Both somatosensory and visual inputs appeared able to trigger the myoclonic jerks. Myoclonic jerks in the deltoid muscle followed finger contact with a target by approximately 100 msec. Electrical stimuli delivered to the fingers during a reaching movement also triggered myoclonic jerks with a similar latency and also evoked giant cortical potentials which preceded the myoclonic jerks in deltoid by 15-20 msec. Our results suggest that during sensory guided movements, sensory inputs relevant to successful completion of the movement may have access to motor systems controlling the muscles involved. In our patient, who likely has lesions involving the cerebellar nuclei and/or cerebellar cortex, these sensory inputs appeared to result in an excessive motor response, possibly through mechanisms involving cerebellar-motor cortex connections.

Adult↗
PubMed1991

Multi-joint reaching movements and eye-hand tracking in cerebellar incoordination: investigation of a patient with complete loss of Purkinje cells.

Performance on an eye-hand tracking task and a multi-joint reaching movement to a visual target was studied in a patient with stable cerebellar ataxia and in control subjects. The patient subsequently died and a full neuropathological examination was performed. The neuropathological findings were similar to those seen in patients with paraneoplastic cerebellar degeneration, but no tumor was found at autopsy eight years after onset of the patient's cerebellar syndrome. A severe cerebellar cortical degeneration with complete Purkinje cell loss was demonstrated, whereas cerebellar nuclei and brainstem structures showed no neuronal loss. Tracking performance by the patient was characterized by abnormally large numbers of high velocity movements and hand direction reversals, and by excessive lagging of the hand behind the target in time. In the multi-joint reaching movement, the patient showed a delay in movement onset at the elbow joint compared to movement onset at the shoulder joint. The velocity profile of the movement at the shoulder joint was abnormal. The duration of the acceleration phase was poorly correlated with both peak angular velocity and the duration of the deceleration phase. One of the most striking findings was the inability of the patient to consistently produce the same movement direction from trial to trial while reaching to the same target. Our data suggests that the cerebellar cortex is involved in multiple aspects of motor control including visuomotor integration mechanisms.

Adult↗
PubMed1990

Effects of unexpected perturbations on trajectories and EMG patterns of rapid wrist flexion movements in humans.

To investigate how motor programs can be modified by sensory inputs we recorded kinematic and EMG patterns from normal human subjects performing well-practised wrist flexion movements in response to an auditory tone. On random trials unexpected wrist perturbations were introduced at varying times after the signal to move had been given. Extension perturbations delivered before agonist EMG onset resulted in an increased maximum velocity (MV) during the wrist flexion movement and in an increased target overshoot even though the wrist was further from the target than expected by the subject at the onset of the movement. The first agonist EMG burst and the antagonist burst were both increased in magnitude in these perturbed trials. Flexion perturbations delivered before the agonist EMG onset moved the hand nearer to the target just prior to movement onset. These resulted in a reduced MV, but the expected increased target overshoot did not occur. The first agonist burst was reduced in magnitude, and the antagonist burst was increased in magnitude. Perturbations delivered after agonist EMG onset produced less change in the first agonist and antagonist EMG burst, and less compensation for the perturbation was evident in wrist position and velocity recordings. These results indicate that, at least in some situations, motor programs for rapid voluntary movements can be modified by afferent inputs. This interaction between central motor commands and sensory feedback might occur at the cortical or spinal level, depending on when perturbations occur relative to onset of EMG and movement. The timing of the EMG changes suggest that both reflex mechanisms and longer latency 'voluntary' adjustments contribute to the compensatory changes in movement trajectory.

Adult↗