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Biomedical subjects

S Ferris

Publications and source records attributed to S Ferris.

10 recordsLinked to original sources
PubMed1990

Isolation of recombinant fragments of the major outer-membrane protein of Chlamydia trachomatis: their potential as subunit vaccines.

Recombinant fragments of the major outer-membrane protein (MOMP) of Chlamydia trachomatis, expressed at high levels in Escherichia coli, were isolated and purified. Antisera to the recombinant proteins reacted preferentially with overlapping synthetic peptides covering the immunoaccessible variable segments of MOMP. These sera also reacted in a species-specific manner with the surface of intact infectious elementary bodies, and in a Chlamydia genus-specific manner in assays using denatured or bound chlamydial antigens. The ability of recombinant MOMP preparations to elicit antibody to the surface of chlamydial elementary bodies raises the possibility that these proteins may be useful for chlamydial vaccine development.

Animals↗
PubMed1990

The major outer-membrane proteins of Chlamydia trachomatis serovars A and B: intra-serovar amino acid changes do not alter specificities of serovar- and C subspecies-reactive antibody-binding domains.

The major outer-membrane protein (MOMP) of Chlamydia trachomatis is a promising candidate antigen for chlamydial vaccine development. We have sequenced the MOMP genes for a serovar A and a serovar B isolate and have compared these new sequences with those already reported. Intra-serovar changes in the inferred amino acid sequences of the surface-exposed variable segments known to be responsible for binding of neutralizing antibody were observed. Nevertheless, epitope mapping with solid-phase peptides showed that these intra-serovar changes did not affect the binding of serovar- and subspecies-specific, potentially protective antibodies. Variable segment 1 of C. trachomatis serovar A contained two adjacent antibody-binding sites, one of which was C-subspecies specific while the other was serovar A specific. Therefore the subspecies binding site for C-complex organisms is in variable segment 1, whilst that for B-complex organisms is in variable segment 4. This work shows that MOMP sequences are relatively stable within the serovar categorization for isolates taken decades apart from different continents. Within a given serovar, however, limited interchange of functionally related amino acids may occur without impairing the binding of serovar-specific antibody.

Amino Acid Sequence↗
PubMed1979

The misplaced-objects task: a brief test for memory dysfunction in the aged.

A brief, simple test for memory dysfunction in the aged is presented. Materials for the test consist of: 1) a board on which the cross-section of a seven-room house is imprinted, and 2) representations of 10 objects frequently misplaced in the home (e.g., keys). The task of the subject is to place the objects in rooms on the board and, after an interval of 5--30 minutes, to recall the location of each object. The measure is appropriate for a broad range of aged subjects, since performance requirements are minimal and readily apparent. The task has obvious face validity, which is essential for maintaining appropriate motivation in many aged subjects. Discriminate validity was demonstrated in a study in which significantly fewer objects were recalled by 60 aged persons with memory impairment (-x = 6.0) than by 44 unimpaired aged persons (-x = 8.9) or 63 young normal persons (-x = 9.9). Satisfactory test-retest reliability was demonstrated by a correlation of .84 between performances on two consecutive days in a subgroup of 20 impaired patients. Subjects appeared to enjoy the game-like structure of the test and clearly were not threatened by the test procedures. Suggestions are offered for further development of the measure.

Aged↗
PubMed1978

The effects of hyperbaric and normobaric oxygen on cognitive impairment in the elderly.

Eighty-two elderly subjects with significant cognitive impairment were randomly assigned to treatment with either hyperbaric oxygen, hyperbaric air, normobaric oxygen, or normobaric air. Treatment consisted of two 90-minute sessions a day for 15 consecutive days. Subjects were evaluated on measures of memory and intellectual capacity, as well as on psychiatric symptom rating scales. Results immediately after treatment and at one, two, three, and eight weeks following treatment did not show enhanced cognitive functioning or significantly greater symptom reduction in experimental subjects who received either normobaric or hyperbaric oxygen as compared to controls who received hyperbaric or normobaric air. There was also no evidence of differential treatment effects as a function of initial severity of illness, sex, response to a CO2 loading test, or presumed evidence of cerebrovascular disease.

Aged↗
PubMed1978

A controlled crossover study of triiodothyronine in autistic children.

A placebo-controlled crossover study of behavioral effects of triiodothyronine (T3) was conducted in 30 young clinically euthyroid autistic children. Multiple independent raters and multiple rating scales were used. Except for a few symptoms that were reduced on T3, the drug did not differ from placebo. Time itself accounted for most of the improvement in the whole sample. As a group, the lower IQ children responded to T3. The individual children who were responders could not be defined by any parameter.

Autistic Disorder↗
PubMed1977

The effect of methylphenidate on test performance in the cognitively impaired aged.

It was hypothesized that a central nervous system stimulant with relatively weak peripheral effects would facilitate test performance in the cognitively impaired aged. Twelve elderly subjects participated in a counter-balanced, crossover comparison of 10 mg methylphenidate, 30 mg methylphenidate and placebo. All treatments were administered double-blind as a single dose of oral medication. Neither dosage of active medication was found to effect psychomotor or psychological test performance, subjective report, heart rate or blood pressure. A subsequent open trial of 45 mg methylphenidate resulted in heart rate, blood pressure and subjective changes in two of eight subjects but no effects on test performance. The results suggest that cognitive performance in the moderately impaired aged is unimproved following administration of methylphenidate, and perhaps similar sympathomimetic amines, below a dosage level associated with clinically significant peripheral effects.

Aged↗
PubMed1976

Reaction time as a diagnostic measure in senility.

Both simple and disjunctive reaction times (RT) are known to slow with aging but there is a paucity of information on RT changes in senility. Since disjunctive RT involves cognition in addition to the sensory-motor speed and attentional components of simple RT, it was hypothesized that disjunctive RT would be a reliable index of age-related mental decline. To test this prediction, simple and disjunctive RT were measured in matched groups of 20 normal and 20 cognitively impaired elderly. Simple RT was slower in the senile patients than in the normal subjects, but this difference was accounted for by differences in disjunctive RT. The senile patients showed a much larger performance decrement with respect to disjunctive RT than did the normal subjects--a difference which was not accounted for by differences in simple RT. In a discriminant function analysis, disjunctive RT alone correctly identified the senile patients and the normal subjects with 86% accuracy. Thus, this measure proved to be a reliable index of age-related mental decline. Preliminary data indicate that disjunctive RT slowing is correlated with non-memory mental decline, and that poor performance is related to the need for care and supervision.

Adult↗