PubMed Health⌕ Search

Biomedical subjects

E R Johnson

Publications and source records attributed to E R Johnson.

At least 73 records · Page 4Linked to original sources
PubMed1971

Synonymy of Metschnikowia pulcherrima and Torulopsis burgeffiana.

Torulopsis burgeffiana is placed in the genus Metschnikowia because it has been shown to have a perfect stage corresponding with this genus. Due to the characteristic shape of the ascus and ascospores, T. burgeffiana is to be considered a synonym of M. pulcherrima. The physiological differences which exist between strains are not sufficiently important to maintain a separate species.

Ascomycota↗
PubMedDate not supplied

Blood usage in transfusion-dependent patients. A theoretical model.

A model for blood requirements of transfusion-dependent patients is presented to relate the transfusion interval in days (I), the percentage fall in hemoglobin (F), and the time in days after a transfusion during which no red cell loss occurs (S). The model applies to both normal blood (S = 0) and to young red cell (YRBC) transfusions, giving I = (S + 120)/(200/F - 1) The model predicts prolongation of transfusion interval by use of YRBCs, and is also of use in establishing whether excess red cell destruction or significant red cell production is present in a transfusion-dependent patient receiving either normal blood or YRBCs.

Anemia, Aplastic↗
PubMedDate not supplied

Profiles of neuromuscular diseases. Design of the protocol.

The purpose of this 10-yr investigation was to develop comprehensive impairment and disability profiles of the clinical characteristics of seven neuromuscular diseases: spinal muscular atrophy, hereditary motor sensory neuropathy, Duchenne muscular dystrophy, Becker's muscular dystrophy, facioscapulohumeral muscular dystrophy, limb-girdle syndrome, and myotonic dystrophy. Based on the World Health Organization's classification of disablement, as applied to neuromuscular diseases, impairment was evaluated by measurements of strength, range of motion, spine deformity, cardiac and pulmonary function, and intellectual capacity. Disability was evaluated by measures of mobility and upper extremity function, cardiopulmonary adaptations, cardiac and pulmonary complications, and psychosocial adjustment.

Clinical Protocols↗
PubMedDate not supplied

Profiles of neuromuscular diseases. Duchenne muscular dystrophy.

One hundred and sixty-two patients with Duchenne muscular dystrophy (DMD) were followed over a 10-yr period to provide a profile of impairment and disability. The median height and weight of DMD boys were normally distributed before ages 9-10, but during the second decade height was markedly reduced, and weight was no longer normally distributed. Younger boys gained more weight than normals, whereas older individuals actually showed weight loss. Manual muscle test (MMT) measurements showed loss of strength in a fairly linear fashion from ages 5-13 yr, -0.25 MMT units per year. Upper extremity muscles were stronger than lower extremity muscles, proximal muscle groups were weaker than distal muscle groups, and extensor muscles were weaker than flexor muscles. There was no side dominance. There was a change in the rate of strength loss at 14-15 yr, and the decline slowed to only -0.06 MMT units per year. Although MMT and quantitative strength measurement profiles were similar, the latter were far more sensitive. In general, by the time strength declined to MMT grade 4, isometrically measured strength was 40-50% of normal control values. Joint contractures were rare before age 9, increased in frequency and severity with age, and were present in most individuals older than 13. Lower extremity contractures were strongly related to onset of wheelchair reliance, but there was no association between muscle imbalance around a joint. The prevalence of scoliosis increased between ages 11 and 16, with about 50% of the boys acquiring scoliosis between ages 12 and 15, corresponding to the onset of the adolescent growth spurt. Wheelchair reliance and scoliosis were both age-related. Percent predicted forced vital capacity declined at different yearly rates: ages 7-10, -0.3%; ages 10-20, -8.5%; after age 20, -6.2%. There was a direct relationship between percent predicted FVC and MMT scores. Decreased airway pressures, especially maximal expiratory pressure, appeared earlier than reductions in FVC but followed the same pattern. Thirty percent of the DMD boys had a history of respiratory complications, and the frequency increased with age. Spine deformity did not have a significant additive effect on the age-related decrement in pulmonary function. There was a high occurrence (79%) of abnormal electrocardiograms with age-related progression of some abnormalities, but only 30% of the patients had a history of cardiovascular complications. Functional level grades and timed motor performance measurements had a nonlinear relationship with strength and age.(ABSTRACT TRUNCATED AT 400 WORDS)

Adolescent↗
PubMedDate not supplied

Profiles of neuromuscular diseases. Becker's muscular dystrophy.

Fifteen subjects with Becker's muscular dystrophy (BMD) were studied prospectively over a 10-yr period to provide a profile of impairment and disability. Proximal lower extremity musculature (particularly the hip and knee extensors), ankle dorsiflexors, and neck flexors showed significantly early weakness. Extensor muscle groups were weaker than flexor muscles at the elbow and knee. The mean manual muscle test (MMT) strength grade for all muscle groups combined was 3.7 +/- 0.8 MMT units. There was a slowly progressive decline in strength, only -0.31 MMT units per decade, and the decline was relatively equal in all muscle groups. There was not side dominance. Severe contractures did not appear to be a problem until after transition to a wheelchair, and scoliosis was rare. Restrictive lung disease occurred as a late complication in a small percentage of cases; however, maximal expiratory pressure was significantly reduced early in the disease. Only two individuals (19%) had severe restrictive lung disease and a history of significant respiratory complications. There was a slight but significant decline in forced vital capacity and maximal expiratory pressure with age and disease duration. The cardiomyopathy in BMD appeared to be disproportionately severe in some cases. Eleven individuals (73%) had abnormal electrocardiograms, and five (25%) had a history of significant cardiovascular complication, with no age or disease duration effect. Functional evaluations and timed motor performance tests showed only mild disability in most individuals. Mean intellectual and neuropsychologic function was within normal limits, but with a large variability in intelligence quotient scores. This report and others suggest a tremendous heterogeneity of severity among males with BMD.

Adolescent↗
PubMedDate not supplied

Profiles of neuromuscular diseases. Limb-girdle syndromes.

Sixty-six individuals with Limb-Girdle Syndrome (LGS) were evaluated over a 10-yr period and classified into three types: 19 severe autosomal recessive muscular dystrophy of childhood (ARMDC), alternatively referred to by some as SCARMD, 18 autosomal dominant late onset (ADLO), and 29 pelvifemoral (PF) individuals. ARMDC subjects showed the greatest weakness, 2.5 +/- 1.0, mean Manual Muscle Test (MMT) grade for all muscles combined, and the only significant progression of loss of strength, -0.59 MMT unit decline per decade. Strength loss in ADLO and PF types was about the same, 3.7 +/- 0.7 and 4.0 +/- 0.7 grades, respectively. Quantitative strength measurements in ADLO and PF types were more sensitive than MMTs, showing losses of 30-40% strength in muscle groups with MMT grades of 4 or higher. All three types showed greater proximal and lower extremity weakness but usually no difference between flexor and extensor strength. There was a high percentage (44%) of mild very slowly progressive scoliosis in ARMDC, but spine deformity was unusual in ADLO and PF (11%) LGS. Contractures were few, slowly progressive, and usually mild in severity in all types, although more frequent in ARMDC. There also was a low frequency of severe restrictive lung disease in all types (10%) but a high percentage of electrocardiogram abnormalities (62-73%). The most common electrocardiogram abnormalities were increased R/S ratio in V1 and infranodal conduction defects. Intellectual and cognitive functions were within normal limits. Mobility and extremity function reflected the strength differences between the ARMDC and other types of LGS. Eight-five percent of ARMDC individuals relied on a wheelchair for all or part of their mobility, and all were unable to complete timed motor performance tests within the 99th percentile range for controls.

Adolescent↗
PubMedDate not supplied

Profiles of neuromuscular diseases. Facioscapulohumeral muscular dystrophy.

Data were collected prospectively over a 10-yr period from 53 subjects with facioscapulohumeral muscular dystrophy (FSHD) to provide a profile of impairment and disability. Manual muscle testing (MMT) indicated greater involvement of proximal musculature, although a subgroup demonstrated early weakness of the ankle dorsiflexors. Asymmetry of upper extremity musculature was noted, with greater weakness of selected dominant limb muscle groups. Weakness, in general, was relatively mild, with an overall mean MMT score of 3.7 units. The rate of strength loss was quite slowly progressive, a decline of only -0.22 MMT units per decade of age. An early age of onset was associated with greater likelihood of more severe and progressive weakness. Isometric and isokinetic quantitative strength testing revealed that all muscle groups were 36-68% weaker than a control population. Although nearly 50% of the subjects had vital capacity evidence of restrictive lung disease, only 13% had severe involvement, and only 22% had a history of pulmonary complications. There was no age or disease duration effect on pulmonary function measurements or complications. As with the other neuromuscular diseases, maximal expiratory pressure measurements were more sensitive than other pulmonary function tests. Abnormal electrocardiogram findings were rare and minor and not related to overt cardiac disease. Contractures were rare and mild. Thirty-five percent of the patients had spine deformity; however, most had hyperlordosis. Intellectual function was normal, and there were few abnormalities on personality tests. Functional testing demonstrated wide variation in disability with FSHD, but motor weakness uniformly translated into impaired motor performance skills. This profile demonstrates the clinical heterogeneity of FSHD.

Adult↗
PubMedDate not supplied

Profiles of neuromuscular diseases. Hereditary motor and sensory neuropathy, types I and II.

Data were collected prospectively for an impairment and disability profile for 86 hereditary motor and sensory neuropathy, types I and II (HMSN) subjects over a 10-yr period. Our data confirm that HMSN is a slowly progressive disorder that has a very heterogeneous phenotypical expression. The disorder was characterized primarily by diffuse muscle weakness with prominent distal atrophy. The mean manual muscle test (MMT) strength grade for all muscle groups combined was 3.9 +/- 0.7 MMT units. There was a slowly progressive decline in strength, only -0.15 MMT units per decade. Distal muscle groups were weaker than proximal muscles, and the decline in strength of the ankle muscles was greater than for the proximal muscles. There was no side dominance. Anthropometric data revealed that distal atrophy may be masked by subcutaneous fat in female subjects. On average, HMSN subjects produced 20-40% less force than normal controls, using quantitative isometric and isokinetic strength measures, even when MMT scores were normal. Pulmonary and cardiac abnormalities were uncommon, as were spine deformity and joint contractures. Only 1 individual had severe restrictive lung disease, and 12 (14%) had a history of significant respiratory complications with no age or disease duration effect. As with the other neuromuscular diseases, maximum expiratory pressure was more affected than forced vital capacity. Fourteen individuals (30%) had abnormal electrocardiograms, and six (7%) had a history of significant cardiovascular complications with no age or disease duration effect. Kyphosis was the major spine deformity. Cardiopulmonary responses to exercise testing were markedly abnormal, showing reduced aerobic capacity. Functional evaluations and timed motor performance tests showed only mild disability in most individuals. With timed motor performance testing muscle weakness translated to impaired motor performance skills. Overall, mean scores on intellectual function and neuropsychologic profiles were normal.

Adult↗