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Biomedical subjects

N O'Connor

Publications and source records attributed to N O'Connor.

At least 37 records · Page 2Linked to original sources

Synthesis and properties of a photoaffinity labeling reagent for protoporphyrinogen oxidases, the target enzymes of diphenyl ether herbicides.

A diazoketone 3 has been synthesized in two steps from acifluorfen 1, a diphenyl ether herbicide. Like the parent compound 1, the diazoketone 3 is toxic to plant cells and inhibits protoporphyrinogen oxidase, the molecular target of diphenyl ether herbicides. On photolysis of 3 in methanol, the generated carbene mainly undergoes the Wolff rearrangement to a ketene which further adds methanol, but many other products are observed. A tritiated derivative of 3 has been prepared which is suitable for photoaffinity labeling experiments.

Affinity Labels↗

Postmastectomy complications in breast reconstruction.

In a group of patients where breast reconstruction was performed at the time of mastectomy, the incidence of complications was studied. One hundred one consecutive patients had an autologous reconstruction using the transverse rectus abdominis musculocutaneous flap, and 115 consecutive patients had a prosthetic reconstruction with tissue expanders or with tissue expander and/or implant. One patient in the autologous reconstruction group had a cardiac arrhythmia requiring monitoring, but there were no other serious complications. Infection was more common in the group undergoing prosthetic reconstruction (5% compared with 3% in the autologous reconstruction group). A total of 8% of the patients in the group undergoing prosthetic reconstruction had to have their implants removed because of infection or exposure of the implant. Seven percent of the transverse rectus abdominis musculocutaneous flap patients had significant necrosis of a portion of the flap. Secondary surgical revision of the reconstructed breast was much more common (20%) in the prosthetic reconstruction group compared with 6% in the autologous reconstruction group.

Adult↗

The amalgam controversy.

Silver amalgam restorations, containing mercury, have been used for over a century. This review paper examines the recent literature regarding the possible adverse effects on health of the use of mercury.

Dental Amalgam↗

An analysis of social and psychological characteristics of women volunteering to become oocyte donors.

OBJECTIVES: To design a recruitment program and analysis to determine social and psychological characteristics of women who volunteer to be oocyte donors; to evaluate consistency between clinical interviews and psychological testing; and to determine whether socially and psychologically normal women tend to volunteer. PARTICIPANTS: Over a 2-year period 95 women were recruited from a middle-class population surrounding the medical center. Candidates were evaluated on the basis of clinical interviews and performance on the Minnesota Multiphasic Personality Inventory. Seventy-three percent were accepted, and 63% donated oocytes. INTERVENTIONS: Interviews and psychological test evaluation were conducted independently by a clinical sociologist and a clinical psychologist; selections were made in a meeting of the treatment team. RESULTS: Interview and test data demonstrated consistency and indicated that women who volunteer tend to be socially conventional, outgoing, and free from psychopathology. The typical donor tends to be 26 years old, married with one or two children, holds religious or spiritual beliefs, has 2 years of college, works at least part-time in a white collar job, and is a person with high energy who has additional interests. Incidence of dysfunction in family of origin or family of orientation (abandonment, abuse) is unremarkable. Although motherhood is highly valued by oocyte donor volunteers, in test performance this group does not endorse traditional female role stereotypes. CONCLUSIONS: We have determined that this recruitment protocol is reliable for screening normal oocyte donors and would recommend its use in programs involved in oocyte donation.

Adult↗

Do young calendrical calculators improve with age?

The calendrical calculation performance of two 10-year-old children of the same intelligence level (IQ 90) but different calendrical ability, was compared with the performance of eight adult idiot-savant calculators. The calculating speeds of the two 10-year olds fell within the range of the reaction times of the adult savants. No improvement was detectable in a series of successive trials over time, either in speed or accuracy. It is concluded that the young calculators have already inferred rules about calendrical structure and that their performance cannot be accounted for by practice alone, but these savants use cognitive strategies to aid their performance.

Adolescent↗

Talents and preoccupations in idiots-savants.

The question was asked whether a diagnosis of autism or a tendency to repetitive behaviour and preoccupation with a restricted area of interest, were crucial features of idiot-savant talents. Answers by caretakers to a questionnaire on these topics revealed that autistic and nonautistic savants resembled each other closely in preoccupation but differed from controls matched for IQ and diagnosis. In addition, the mentally handicapped showed fewer repetitive tendencies than did autistic controls. It is concluded that independent of diagnosis, preoccupations and repetitive behaviour appear to be closely associated with the manifestation of idiot-savant talents.

Aptitude↗

A specific linguistic ability.

A young man with diagnosed hydrocephalic brain injury was found to be an able linguist. His ability to translate into English from French, German, and Spanish was confirmed to be at a high level, and his capacity to express thoughts and describe scenes in these languages was also verified. A set of translations of the Peabody Picture Vocabulary Test was prepared in French, German, and Spanish, and IQs were derived in each language. The subject's performance intelligence was tested separately and found to be low, especially in relation to spatial reasoning. The subject's linguistic achievements were discussed in terms of an IQ-independent linguistic talent.

Adult↗

Factors and primes: a specific numerical ability.

An autistic young man and a normal control were asked to factorize numbers and to recognize and generate primes. Both subjects made a similar number of errors and employed similar strategies, but they differed markedly in the speeds at which the arithmetical operations were carried out.

Adult↗

The recognition failure and graphic success of idiot-savant artists.

Three groups of subjects, an idiot-savant group, a group of mentally handicapped subjects matched for IQ, and normal artistically gifted children, were compared for their recognition and graphic reproduction abilities. It was found that, independent of input modality, level of intelligence determined recognition performance, while graphic ability independent of IQ was the determining factor in reproduction accuracy.

Adolescent↗

Art and accuracy: the drawing ability of idiot-savants.

The accuracy and the artistic merit of drawings produced by graphically gifted idiot-savants and by artistically able normal children were investigated in various conditions. Drawings had to be executed when a three- or two-dimensional model of the scene to be drawn was in view, or when it had to be remembered or drawn from another viewpoint. It was found that overall accuracy was better for the normal than for the mentally handicapped subjects. In contrast, ratings for artistic merit did not differentiate the groups. It is concluded that while the accuracy of drawings may be related to intelligence, the artistic quality of the graphic production is not.

Adolescent↗

Fatal cutaneous T cell lymphoma in a child with atopic dermatitis.

The development of a fatal cutaneous T cell lymphoma in a child with atopic disease is presented. From very early childhood the patient had classic atopic dermatitis, and at age 13 developed lymphoma-like skin tumors. The diagnosis--based on immunohistologic criteria--was initially difficult to establish, but cytogenetic and DNA studies of the dermal infiltrate supported the clinical suspicion of malignancy. In addition, the T cell receptor beta chain gene showed a clonal rearrangement pattern both in skin and in lymph node, suggesting malignancy. Whether the malignant evolution in our patient took place primarily in the skin or in the lymph nodes is difficult to decide. Further examination of the association between atopic dermatitis and cutaneous T cell lymphoma may lead to insights into both disorders.

Adolescent↗

Intelligence and musical improvisation.

We investigated whether somebody with a severe mental impairment could not only remember and reproduce music, but was also able to generate it. Musical improvisation requires the ability to recognize constraints and also demands inventiveness. Musical improvisations on a traditional, tonal and also on a whole tone scale composition were produced by a mentally handicapped and by a normal control musician. It was found that not only the control but also the handicapped subject could improvise appropriately within structural constraints, although with the tonal music the idiot-savant showed some stylistic latitude. It is concluded that cognitive processes such as musical input analysis, decision making, and output monitoring are independent of general intellectual status.

Adult↗

The memory structure of autistic idiot-savant mnemonists.

The memory organization of six autistic mnemonists was investigated in two experiments. The first of these provided some evidence that the material of special interest to the subjects, in the present instance bus numbers, was stored in memory in a categorized form. The second study showed that though the idiot-savant mnemonists did not differ from controls in the level of their general memory performance, the factor structure of a number of memory tests differed between the groups. In contrast to the controls, a verbal memory factor which seemed independent of measured verbal IQ was operative in the mnemonist subjects.

Adolescent↗

The 1988 Jansson memorial lecture. The performance of the 'idiot-savant': implicit and explicit.

'Idiots-savants' are people of low intelligence who have one or two outstanding talents such as calendrical calculation, drawing or musical performance. Such people are mostly male and occur with high frequency among the autistic population. Do they perform their amazing feats because of an outstanding memory or do they draw on some faculty of reasoning to help them? Although they cannot easily make clear how they carry out their tasks by using speech, experiments reveal that they follow simple rules which they use to aid them in recalling correct dates and sequences in classical music. It has been said that they cannot abstract but this turns out not to be true: all can abstract to some degree and some are more at home with abstract than with concrete material. Whatever else is true of these handicapped but gifted people their gift becomes apparent at an early age and is apparently not improved by practice. Perhaps the most important conclusion from work with these groups is that their gifts force us to think again about the concept of general intelligence. How far is it possible to have low intelligence and yet be an outstanding musician or artist? Speculation on this idea may force us to revise our concepts of intelligence, neuropsychology and handicap.

Aptitude↗

The toxicity of mercury--myth or reality?

The use of mercury in dentistry has provoked considerable controversy. The pharmacology and possible signs and symptoms associated with the use of mercury are considered and evidence regarding its safety is examined in this review paper.

Air Pollutants, Occupational↗