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P McNamara

Publications and source records attributed to P McNamara.

At least 19 recordsLinked to original sources
PubMed1995

Favor referential representations.

Avrutin and Hickok (1993) argue that agrammatic patients have the ability to represent nonreferential or "government" chains ("who ... e") but not referential or "binding" chains ("which girl ... e"). By contrast, we propose the "referential representation hypothesis," which suggests that agrammatics attempt to cope with their well-known capacity limitations by favoring referential or content-based representations. This predicts that agrammatic patients' performance should degrade noticeably as task demands increase, and referential demands should take priority over computational ones. In a semantic task, referential phrases should lead to better or more accurate performances. In syntactic tasks, the availability of a referential or content-based representation will interfere with the development of a syntactic representation, resulting in worse syntactic performance on the referential phrases than on nonreferential ones. This predicts that agrammatic patients should incorrectly accept (resumptive) pronoun sentences with a referential wh-phrase because the pronouns will find the semantic or discourse referent of the referential wh-phrase and take it as an antecedent for the pronoun. However, they should reject a (resumptive) pronoun in a sentence with the nonreferential question constituent "who" or "what." "Who" and "what" will remain in syntactic form, since they have only grammatical content and therefore will have only a "nonreferential" syntactic representation. Consequently, they cannot serve as the antecedent of the pronoun. These predictions were largely confirmed by the results of a grammaticality judgement study. Agrammatics performed well on questions with pragmatic biases but failed to distinguish reliably between grammatical and ungrammatical questions where pragmatic biases were neutralized. They assigned especially low ratings to object gap sentences with referential wh-constituents, as predicted. They assigned relatively high ratings to ungrammatical subject pronoun sentences with either type of wh- constituent. The agrammatics accepted ungrammatical reflexive sentences even though syntactic number and gender features alone could have been used to correctly judge the sentences. We attribute this, too, to the unavailability of a reliable syntactic representation of those phrases with referential or extragrammatical semantic content.

Adult↗
PubMed1994

Memory, double, shadow, and evil.

In order to examine shadow dynamics the author explores the phenomenology and mythological associations of the 'double' or Doppelgänger. Current Jungian-inspired theories concerning relations of shadow and double are found to be limited because they do not explain (1) the process of personification of the psychic complex which gives rise to the double, (2) the immediate conditions under which doubling occurs, (3) the conditions which lead to the assignment of evil qualities to the double as shadow. The paper seeks to remedy each of the above limitations by redescribing shadow/double phenomena in terms of autonomous memory phenomena, both personal and trans-personal.

Brain↗
PubMed1994

Cloning of a Cryptococcus neoformans gene, GPA1, encoding a G-protein alpha-subunit homolog.

We have isolated a gene, GPA1, from Cryptococcus neoformans by the PCR technique. DNA sequencing of the GPA1 clone suggested that it encodes a protein homologous to the G-protein alpha-subunit family. Comparison of the deduced amino acid sequence of the GPA1-encoded protein revealed that it is about 45% identical to several mammalian Gi alpha subunits and 48% identical to the G alpha protein Gpa2 from Saccharomyces cerevisiae. G alpha proteins are known to be involved in mating of other yeasts, such as S. cerevisiae and Schizosaccharomyces pombe. Southern analysis demonstrated that GPA1 is present in a single copy within the Cryptococcus genome. Isolation of the cDNA for GPA1 confirmed that the gene contains six introns within the coding region. The GPA1 transcript was identified by Northern (RNA) analysis as a 1.6-kb RNA present in exponentially growing cells of both the alpha and a mating types. Moreover, the abundance of this transcript increased in cells shifted to starvation medium. Coincubation of alpha and a cells on starvation medium is required for mating of cryptococcal cells. Thus, our results are consistent with the involvement of C. neoformans GPA1 in mating.

Amino Acid Sequence↗
PubMed1994

Markers of cerebral lateralization and alcoholism.

We assessed markers of anomalous cerebral dominance in 70 problem drinkers at risk for alcoholism, 43 alcoholics who had been sober for at least six months, and 311 healthy control subjects age-matched to the problem drinkers. Markers of anomalous cerebral dominance included left-handedness, learning disabilities, neuro-immune disorders, and special cognitive talents. We also administered a "drinking inventory" to assess frequency and severity of drinking patterns for self and family. Analysis showed elevated rates of left-handedness and learning disabilities in the alcoholic group and in the "at risk" problem drinkers. These same subjects rated themselves and their families as relatively poor at left-hemisphere-mediated cognitive talents. Alcoholic women evidenced significantly greater incidence of immune disorders than alcoholic men. Alcoholism appears to be related to biological factors which have been associated with anomalous cerebral dominance.

Adolescent↗
PubMed1994

Special talents in Geschwind's and Galaburda's theory of cerebral lateralization: an examination in a female population.

Geschwind and Galaburda (1985) proposed that delayed growth of posterior left hemisphere sites in male dyslexics are associated with markers of anomalous dominance (AD) and special cognitive talents. We found that talent in a female population was related to the strength of nonright-handedness, and was elevated in right-handed individuals with histories of familial left-handedness. Subjects reporting a history of dyslexia tended to be musically talented. While immune disorders were not related to talent for the whole population, they did co-occur with talents in a group of 10 individuals reporting 7 or more AD markers.

Adult↗
PubMed1992

The sagging safety net. Emergency departments on the brink of crisis.

U.S. hospitals are facing an emergency care crisis. At the same time emergency departments are overflowing with uninsured patients seeking primary care, violence-related trauma cases are soaring, leaving underfunded trauma systems on the verge of collapse. In a special cover package, we explore the causes of the crisis, the current prospects for change, and related issues in emergency care today. Beginning on page 26, we present an overview of the crisis, with particular attention to the breakdown of trauma systems. Starting on page 30, we look at the growing threat of violence itself entering hospital EDs; on pages 34-35, we examine how hospitals are attracting and retaining critically needed clinicians, and how trauma systems are dealing with ongoing shortages of specialists. On pages 37-38, we explore the patient satisfaction question; and on pages 38-39, we present the latest data on emergency care utilization from the American Hospital Association.

American Hospital Association↗
PubMed1992

Speech monitoring skills in Alzheimer's disease, Parkinson's disease, and normal aging.

We examined the abilities of 15 patients with dementia of the Alzheimer type (DAT), 22 patients with Parkinson's Disease (PD), and 141 healthy subjects (ranging in age from 30 to 79 years) to detect and correct their own speech errors. Each subject was shown the Cookie Theft picture of the BDAE (Goodglass & Kaplan, 1972. The assessment of aphasia and related disorders. Philadelphia: Lea & Febiger.) and instructed to tell the examiner the "...story of what's happening in the picture." Self-monitoring performance was assessed by tabulating the number of uncorrected errors as well as repaired errors. We divided repairs into two types based on the psycholinguistics literature (van Wijk & Kempen, 1987. Cognitive Psychology, 19, 403-440). Speech corrections were judged to be lemma repairs when the reparandum was a single word, and reformulation repairs when a new syntactic constituent was added to the reparandum. Patients with DAT corrected only 24% of their total errors and patients with PD only 25%. Healthy subjects, by contrast, corrected from 72 to 92% of their total errors. Patients with DAT tended to rely on reformulation repairs while patients with PD used both repair types about equally often. While healthy elderly Ss (in the 70s group) utilized lemma repairs more often than the reformulation strategy, all other healthy Ss used both strategies about equally often. Across all groups naming performance correlated negatively with numbers of undetected errors. Results point to a previously unrecognized communication disorder associated with PD and DAT and manifested by an impairment in the ability to correct output errors. This impairment may be related to attentional and frontal dysfunction in the two patient groups.

Adult↗
PubMed1992

Processing complexity and sentence memory: evidence from amnesia.

This study examines sentence memory as a function of linguistic processing complexity in amnesic patients. Sentence length as well as lexical and syntactic complexity were manipulated in two sentence repetition experiments. It was found that the amnesic patients performed considerably worse than the control subjects and that performance decreased: (1) when sentence length was increased by the addition of adjuncts compared to arguments of the verb; (2) when the verb selected more thematic frames; and (3) when sentences involved "empty" argument positions that must be linked to antecedents, particularly across clausal boundaries. These data showed how linguistic complexity affects sentence memory and implied that the amnesic deficit did not involve a generalized difficulty for materials of similar length, rather, the deficit was specific to certain representational types and processing routines.

Alcohol Amnestic Disorder↗
PubMed1991

Curved DNA without A-A: experimental estimation of all 16 DNA wedge angles.

The principal sequence feature responsible for intrinsic DNA curvature is generally assumed to be runs of adenines. However, according to the wedge model of DNA curvature, each dinucleotide step is associated with a characteristic deflection of the local helix axis. Thus, an important test of a more general view of sequence-dependent DNA curvature is whether sequence elements other than A-A cause the DNA axis to deflect. To address this question, we have applied the wedge model to a large body of experimental data. The axial path of DNA can be described at each step by three Eulerian angles: the helical twist, the deflection angle (wedge angle), and the direction of the deflection. Circularization and gel electrophoretic mobility data on 54 synthetic DNA fragments, both from other laboratories and from our own, were used to compare the theoretical predictions of the wedge model with experiment. By minimizing misfit between calculated and observed DNA curvature, we have found that the stacks AG/CT, CG/CG, GA/TC, and GC/GC, in addition to AA/TT, have large wedge values. We have also synthesized seven sequences without AA/TT elements but with these other wedges correctly phased to cause appreciable predicted curvature. All appear curved as demonstrated by anomalous gel mobilities. The full set of 16 roll and tilt wedge angles is estimated and, together with the known 10 helical twists, these allow prediction of the general sequence-dependent trajectory of the DNA axis.

Adenine↗
PubMed1989

Angiotensin converting enzyme inhibitors: spirapril and related compounds.

The synthesis of spirapril (5), spiraprilat (25), their RSS stereoisomers, and their glycyl (18b) and lysyl (36, 37) analogues is described. These compounds were evaluated in vivo for inhibition of angiotensin converting enzyme (ACE), and selected compounds were evaluated for in vitro ACE inhibition (spirapril ID50 16 micrograms/kg; spiraprilat IC50 0.8 nM, ID50 8 micrograms/kg). In anesthetized rats, iv, esters 5 and 36 are more potent than enalapril, and diacids 25 and 37 are more potent than enalaprilat in vitro. In the conscious rats, orally, 5 and enalapril (2) showed potent and sustained activity at doses of 0.03-1 and 0.1-1 mg/kg, respectively. From this work, spirapril was selected for clinical evaluation as an antihypertensive agent.

Angiotensin-Converting Enzyme Inhibitors↗
PubMed1989

Stereoselective binding of propranolol in the elderly.

The influence of age on the stereoselective serum protein binding of propranolol was investigated. Serum was obtained from 10 young (mean age 23 +/- 2 years) and ten elderly (mean age 68 +/- 2 years) healthy male volunteers. The free fraction of propranolol (fu) was measured by equilibrium dialysis, using tritium labeled (+/-)- and (-)-propranolol. The fu values were 0.159 +/- 0.049 and 0.148 +/- 0.028 (+/-), 0.135 +/- 0.041 and 0.136 +/- 0.04 (-), 0.174 +/- 0.056 and 0.161 +/- 0.028 (+) in the young and elderly subjects, respectively. Serum alpha 1-acid glycoprotein (AAG) concentrations were 81.4 +/- 33.0 and 81.0 +/- 21.6 mg 100 ml-1 in young and elderly respectively (P greater than 0.05). Variability in AAG concentration accounted for most of the observed intersubject variability in the binding of both propranolol isomers. The stereoselective binding of propranolol does not appear to be affected by age.

Adult↗
PubMed1985

The aging thyroid. Thyroid deficiency in the Framingham Study.

In an unselected population of elderly (over age 60 years) men and women (the original cohort of the Framingham Study), the prevalence of thyroid deficiency, evidenced by a clearly elevated serum thyrotropin (TSH) level (greater than 10 microU/mL), was 4.4%. Women had thyroid deficiency (5.9%) more often than men (2.3%). Of those with clearly elevated serum TSH levels, only 39% had low serum thyroxine (T4) levels; the remainder had serum T4 levels in the lower half of the normal range. Others (5.9%) had a slightly elevated serum TSH level (5 to 10 microU/mL); their status was not clear, but more (12.7%) had low T4 levels than expected. The level of serum T4 was not a sensitive measure of thyroid deficiency nor was routine examination by a physician, even when the patient's background contained a clue to a possible thyroid problem. An elevated serum TSH level was a sensitive marker of thyroid deficiency in the elderly and was often the only way to detect it. Further studies are needed to determine the relationship of thyroid deficiency to cognitive and cardiovascular function in older persons.

Aged↗
PubMed1981

Asymptomatic carotid bruit and risk of stroke. The Framingham study.

Carotid bruit was routinely sought in the Framingham cohort and during eight years appeared in 66 men and 105 women, all of whom were asymptomatic. The incidence increased with age equally in the two sexes from 3.5% at 44 to 54 years, to 7.0% at 65 to 79 years. The eight-year incidence was greater in diabetes and hypertensive subjects. Transient ischemic attacks appeared in eight (two alone) and stroke in 21 of the 171, a stroke rate more than twice expected for age and sex. More often than not, cerebral infarction occurred in a vascular territory different from that of the carotid bruit, often in the posterior circulation, and ruptured aneurysm, embolism from the heart, and lacunar infarction was the mechanism of stroke in nearly half the cases. Incidence of myocardial infarction was also increased twofold in those with asymptomatic carotid bruit. General mortality were also increased; 1.7-fold with men, and 1.9-fold in women, with 79% of the deaths owing to cardiovascular disease, including stroke. Carotid bruit is clearly an indicator of increased stroke risk but chiefly as a general and nonfocal sign of advanced atherosclerotic disease and not necessarily as an indicator of local arterial stenosis preceding cerebral infarction.

Adult↗
PubMed1981

Systolic blood pressure, arterial rigidity, and risk of stroke. The Framingham study.

Based on prospective data from the Framingham study relating systolic pressure, diastolic pressure, age, and pulse-wave configuration to future stroke incidence, it would appear that isolated systolic hypertension predisposes to stroke independent of arterial rigidity. The prevalence of isolated systolic hypertension increased with age and with the degree of blunting of the dicrotic notch in the pulse wave. Subjects with isolated systolic hypertension experienced two to four times as many strokes as did normotensive persons. While diastolic pressure is related to stroke incidence, in the subject with systolic hypertension, the diastolic component adds little to risk assessment and in men, in this subgroup, appears unrelated to stroke incidence.

Adult↗
PubMed1981

The preparation and properties of monoclonal antibodies against human granulocyte membrane antigens.

A series of four monoclonal antibodies has been prepared by hybridization of mouse myeloma cells with spleen cells from mice immunized with human blood granulocytes. The four antibodies all react specifically with granulocytes, failing to stain lymphocytes and other blood cells. Lymphocytic leukaemia cells are not stained, whereas myeloid leukaemia cells give a varied reaction with the antibodies. Studies on marrow, leukaemic cells and cell lines suggest that the four antibodies react with distinct differentiation antigens which are absent from myeloblasts, appear at the promyelocyte, myelocyte or metamyelocyte stage (depending on the antibody in question) and are expressed on all mature granulocytes.

Animals↗
PubMed1980

Effect of dietary vitamin E on dimethylhydrazine-induced colonic tumors in mice.

This study investigates the effect of variations in dietary vitamin E on the incidence of dimethylhydrazine-induced colonic tumors in mice. Two groups of 65 LACA mice were given 28 weekly s.c. injections of dimethylhydrazine. The only difference in the management of the two groups was the dietary content of vitamin E; one group received 10 mg/kg, and the other group received 600 mg/kg. Of these two groups, 42 and 51 mice, respectively, survived, and there were significantly more adenomas, more adenomas with pleomorphic cytology, and more invasive carcinomas in the group receiving a low vitamin E supplement to their diet. It is suggested that vitamin E may have some part to play in the multifactorial effect of diet on colorectal carcinogenesis.

Animals↗
PubMed1978

Interaction of chloramphenicol with phenytoin and phenobarbital. Case report.

The effect of chloramphenicol therapy (48 mg/kg/day) on the serum concentrations of phenytoin and phenobarbital was studied in a patient previously stabilized on anticonvulsant medications. Phenytoin, 12 mg/kg/day, and phenobarbital, 5 mg/kg/day resulted in serum concentrations averaging 10.8 microgram/ml before and 30.5 microgram/ml, after chloramphenicol therapy. A reduction in dose of both phenytoin and phenobarbital was required to minimize adverse effects during the course of chloramphenicol therapy. An average daily dose of phenytoin of 9.1 mg/kg resulted in an average serum concentration of 17.8 microgram/ml. A daily dose of phenobarbital of 4.0 mg/kg resulted in an average serum concentration of 37.1 microgram/ml. These changes indicate 50.5% and 40.4% decreases in clearance of phenytoin and phenobarbital. Multiple-dose nonlinear regression analysis of phenytoin and phenobarbital serum concentration data obtained during chloramphenicol therapy indicated a 62.5% and a 29.5% decrease in clearance. Subsequent serum concentration monitoring demonstrated a similar reduction in phenobarbital clearance when chloramphenicol was added to phenobarbital alone.

Adult↗