Search PubMedSearch

Biomedical subjects

M Fitzgerald

Publications and source records attributed to M Fitzgerald.

At least 73 records · Page 4Linked to original sources

Cystic fibrosis in adolescents and adults.

A cystic fibrosis (CF) clinic for adults was established in 1977. We have reviewed the data on 164 patients who attended between 1977 and 1989. Twenty four patients had died, 11 being over 20 years after time of death. Of the 140 patients still alive, 61% were male and 53% were aged over 20 years. Only 55% were diagnosed by 1 year and 88% by 10 years. Almost all patients had respiratory symptoms and sputum culture yielded Pseudomonas species in 69%. Other respiratory problems included major haemoptysis and pneumothorax, each in 10%. We found a wide range of respiratory impairment among older patients. Among 3 patients aged over 23 years the mean (+/- S.D.) percent predicted FEV1 and FVC were 53.3% (+/- 18%) and 71.4% (+/- 20%) respectively. Mean weight in this group was 92.5% (+/- 14) of predicted. Malabsorption occurred in most patients and meconium ileus equivalent occurred in most patients and meconium ileus equivalent occurred in 34%. Other complications were clinical hepatomegaly (16%), diabetes mellitus (9%) and arthropathy (20%). Most patients were taking continuous antibiotics by mouth (89%) and by nebuliser (48%), beta-2 agonists by inhaler (57%) and oral steroids (29%). Almost all were taking multivitamins, pancreatic replacement therapy and multiple nutritional supplements. The number of CF "bed days" grew 12 fold since 1979 and the mean stay in hospital was double the hospital mean. The economic impact was such that over 1/4 of the annual hospital antibiotic budget was expended on CF patients.

Adolescent

Occupational asthma.

Occupational asthma is becoming an increasingly common problem worldwide. To date however, the impact of this disorder in Ireland has not been evaluated. In this present study we document 39 cases of occupational asthma presenting to St. Vincent's Hospital between 1978 and 1988 and evaluate the patient characteristics, the occupationals involved, the causative agents and clinical course and outcome. The characteristics of the occupational asthma group were striking when compared to traditional occupational lung diseases, such as the pneumoconioses. These features were (i) the relatively young age--30 patients (77%) developed their disease by the age of 35, (ii) the presence of a substantial group of women--31% of the study group, and (iii) the relatively rapid onset of asthma after taking up employment--56% had asthma within three years of exposure. In contrast the pneumoconioses affect older, preponderantly male workers who manifest clinically symptomatic disease after decades of exposure. Long standing traditional industries were well represented ranging from milling and the bakery trade to textiles and printing. However, there was an even larger contribution from the more modern, high technology sector particularily the chemical, electronic and plastic industries.

Adult

Collateral sprouting of the central terminals of cutaneous primary afferent neurons in the rat spinal cord: pattern, morphology, and influence of targets.

The capacity of the central terminals of primary afferents to sprout into denervated areas of neonatal spinal cord and the morphology of any novel terminals has been investigated. In rats which had undergone sciatic nerve section on the day of birth, 12 of 18 physiologically characterized intact saphenous hair follicle afferents (HFAs) were labelled intra-axonally with horseradish peroxidase (HRP) were shown to sprout up to 2,000 microns into the deafferented sciatic terminal field. The morphology of these sprouts depended on which area of the sciatic nerve territory was invaded by the afferent sprouts. Six HFAs sprouted into areas normally innervated by glabrous skin afferents and the morphology of the collateral sprouts in this region resembled that of rapidly adapting (RA) afferents. The other six saphenous HFAs had sprouted into sciatic "hairy" skin areas and the morphology of these sprouts, although abnormal, was flame shaped. In rats whose sural, saphenous, and superficial peroneal nerves were cut at birth, 4 of 7 single HRP labelled RA afferents had central terminals that had sprouted into regions of cord normally devoted to "hairy" input. These showed clear signs of HFA morphology despite their peripheral receptive fields remaining in the glabrous skin. The results show collateral sprouting of single cutaneous sensory afferent axons into adjacent inappropriate central target regions following neonatal deafferentation. Such plasticity may provide some compensation following neonatal injury. The morphology of the sprouted terminals is appropriate to the new target area rather than to its functional class and is also independent of the peripheral receptive field location providing an example of central rather than peripheral control over afferent growth patterns.

Afferent Pathways

Neonatal capsaicin treatment induces invasion of the substantia gelatinosa by the terminal arborizations of hair follicle afferents in the rat dorsal horn.

Capsaicin, administered on the day of birth, was found to alter laminar distribution, but not the receptive field properties or the morphology of the collateral arborizations of hair follicle afferents (HFAs) intra-axonally injected with horseradish peroxidase (HRP). Of the 65 HFA terminal arbors in capsaicin treated rats, 46 (71%) were found to enter the substantia gelatinosa (in control rats, 44/165, 27%). All of the collaterals projected to somatotopically normal areas of cord. Dorsal horn shrinkage (21%), as estimated by planimetric measurements of Nissl and acetylcholinesterase-stained material, was only a partial explanation of this result. This idea was supported by the statistically significant increase (27%, P less than 0.05) in the absolute dorsoventral length of collaterals. The results show that the destruction of unmyelinated fibres during the early postnatal period by capsaicin induces HFA invasion into the area that C fibres normally occupy. This invasion suggests that the laminar termination sites for different primary afferent fibres are not altogether specified and that intact neonatal primary afferents have the capacity to sprout into denervated regions of spinal cord.

Animals

Autoradiographic analysis of odontoblast replacement following pulp exposure in primate teeth.

Cell migration and replication associated with odontoblast replacement occurring soon after pulp exposure in primate teeth were studied. Class 5 cavity preparations resulting in pulp exposures were restored with a calcium hydroxide-containing capping agent and amalgam. Eighty-four and 96 h after this the animals were injected with 0.5 microCi/g body wt tritiated thymidine (sp. act. 6.7 Ci/mM). Teeth were extracted 6, 8, 10 and 12 days after treatment. The number of labelled cells as well as the number of grains per labelled cell were counted for odontoblast-like, fibroblast-like and perivascular cells in three 60 x 260 microns zones. These zones represented the odontoblast and cell-free (zone 1), cell-rich (zone 2) and deep pulp (zone 3) areas of normal pulp tissue. Ten sections centred around the mid-point of the exposure were counted for each tooth. Matrix formation and labelled odontoblast-like cells were observed at the interface between the capping agent and the pulp as early as day 8. Other significant findings were: (1) an increase in labelled odontoblast-like cells in zone 1 over time, suggesting a continual influx of differentiating cells; (2) an increase in labelled cells in zone 1 over time with a concurrent decrease in zone 3, suggesting that the influx of cells in zone 1 was from the deeper pulp; and (3) differences in grain counts between zones, treatment times and cell types, indicating that at least two DNA replications had occurred between initial treatment and final odontoblast-like cell differentiation.

Animals

Healing of primate dental pulps capped with Teflon.

The pulps of Rhesus monkey teeth were exposed and capped with three materials: Teflon, a commercial hard-set calcium hydroxide (Ca(OH)2) material, and Ca(OH)2 plus saline. Experimental test periods were 3, 10, and 21 days, and 5 and 8 weeks. After treatment, the teeth were removed and processed for routine histologic evaluation. Teeth treated with the two Ca(OH)2 materials showed resolution of the inflammatory response and hard tissue formation at the exposure site as early as 10 days postoperatively, with consistent healing at 21 days and longer. Teflon had a similar soft tissue healing pattern but at a slower rate. Hard tissue formation at the exposure site in the teeth treated with Teflon was infrequent at the early time periods and present in only 20% of the teeth treated for 5 and 8 weeks. By evaluating the soft and hard tissue responses of the Ca(OH)2-capped and Teflon-capped teeth it may be possible, in future studies, to identify events unique to odontoblast differentiation during pulpal healing.

Animals

The measurement of adolescent adaptive processes in the clinical interview.

A study is described measuring the clinical usefulness of Adolescent Adaptive Process Scales. These processes are measured in three groups of adolescents in which psychopathology is also measured using a standardized psychiatric interview. Inter-rater reliability is calculated between two raters and mean score comparisons are made between the groups using the t-test method. In the study a higher inter-rater reliability and some preliminary evidence of construct validity are found for these scales. The findings indicate that these scales could constitute a useful clinical tool in psychotherapy, research and teaching. They also provide scope for future work in the field.

Adaptation, Psychological

Prevalence of psychological distress in Irish female adolescents.

Some female adolescents (N = 132) attending two inner city Dublin schools completed the Youth Self Report Questionnaire (YSRQ). Of this group 15.4 per cent obtained a Total Problem Score in the clinical range. A higher proportion, 23 per cent, obtained a score in the clinical range on one or more problem subscales of the YSRQ. No one scored abnormally on the Social or Competence Scales. A number of interesting and thought provoking responses to individual questions were obtained. The possible clinical relevance of these findings and implications for future planning in schools are discussed.

Adolescent

Psychological health status of mothers and the admission of children to hospital for gastroenteritis.

The prevalence of psychological distress was measured by the 30-item general health questionnaire in two populations of mothers: those who had children hospitalized for gastroenteritis and those who cared for children with gastroenteritis at home. Significant differences emerged, with mothers of hospitalized children reporting higher levels of psychological distress. There were no differences in severity of the children's illness between the two groups as indicated by blind ratings of symptomatology from six infectious diseases hospital doctors. Thus hospitalization of children for gastroenteritis was not contingent on medical symptomatology. Instead the evidence indicates that the psychological status of mothers may influence doctors' management decisions on childhood gastroenteritis. Significant positive associations between poor psychological status and poor social resources illustrate the social context in which maternal vulnerability may influence child health care generally. The impact of maternal psychological status on decisions about paediatric care is discussed.

Adult

Transcription of the rat and mouse proenkephalin genes is initiated at distinct sites in spermatogenic and somatic cells.

During spermatogenesis, several genes are expressed in a germ cell-specific manner. Previous studies have demonstrated that rat and mouse spermatogenic cells produce a 1,700-nucleotide proenkephalin RNA, while somatic cells that express the proenkephalin gene contain a 1,450-nucleotide transcript. Using cDNA cloning, RNA protection, and primer extension analyses, we showed that transcription of the rat and mouse spermatogenic-cell RNAs is initiated downstream from the proenkephalin somatic promoter in the first somatic intron (intron As). In both species, the germ cell cap site region consists of multiple start sites distributed over a length of approximately 30 base pairs. Within rat and mouse intron As, the region upstream of the germ cell cap sites is GC rich and lacks TATA sequences. A consensus binding site for the transcription factor SP1 was identified in intron As downstream of the proenkephalin germ cell cap site region. These features are characteristic of several previously described promoters that lack TATA sequences. Homologies were also identified between the proenkephalin and rat cytochrome c spermatogenic-cell promoters, including the absence of a TATA box, a multiple start site region, and several common sequences. This promoter motif thus may be shared with other genes expressed in male germ cells.

Amino Acid Sequence

Teaching recognition skills to improve products.

All 86 first year dental students in a Conservative Restorations course completed five sets of instructional tasks. Tasks followed a discrimination learning paradigm, a sequence based on the principal that recognition skills are a prerequisite for production skills. Recognition skill measures and production quality measures were collected for pre- and post-test Class 1 amalgam preparations. Significant improvement was found in three of the five recognition skill measures and in quality of production. Stepwise multiple regression analysis showed that a measure of student agreement with faculty evaluations accounted for 46.3 percent of the variance in post-test production scores whereas traditional admissions measures accounted for less than 4 percent of the variance. Additionally, students who improved recognition skill showed a corresponding improvement in products. The paradigmatic teaching model appears to be valid for Class 1 cavity preparations.

Dental Amalgam

Morphology and somatotopic organization of the central terminals of hindlimb hair follicle afferents in the rat lumbar spinal cord.

The morphology of the central collateral arborizations of 24 A-beta hair follicle afferents (HFAs) innervating different regions of the skin of the hindlimb were studied by the intra-axonal injection of horseradish peroxidase (HRP) in adult rats. A total of 236 collaterals were recovered. These fell into three classes--complex, simple, and blind-ending--based on numbers of boutons and terminal branch patterns. The morphology of the HFA central arbors innervating the lateral and medial leg and dorsum of the foot was flame-shaped. Afferents with receptive fields on the glabrous-hairy skin border consistently had extra terminal branches running ventromedially into laminae IV/V. Differences in the width of terminal arbors were found. HFA terminals innervating the lateral leg formed narrower sheets than those innervating the dorsum of the foot and toes. The somatotopic organization of the collaterals and terminal arborizations of individual afferents were analyzed both by considering all the collaterals along an axon's rostrocaudal extent and by only examining arbors with boutons (the complex and simple arbors). Thirty-seven percent of blind-ending and 18% of simple collaterals were found to overlap in the rostrocaudal direction with the complex arborizations of afferents whose receptive fields were in a different cutaneous nerve territory. There was no overlap between complex arborizations of afferents from different nerve territories. However, the complex arbors of afferents with receptive fields within a particular nerve territory showed considerable terminal overlap even if they had nonadjacent peripheral receptive fields. The topographical organization of the central terminals of HFAs, forms a coarse somatotopic map of overlapping terminals whereby a particular region of dorsal horn has a maximal, but not exclusive, input from a particular area of skin.

Action Potentials

Cardiac transplantation in the seventh decade of life.

Twenty-five patients older than 60 years of age underwent cardiac transplantation using an immunosuppression protocol with cyclosporin and azathioprine, but without routine use of oral steroids. There were 24 men and 1 woman (age range 60 to 69 years, mean 63). The etiology of heart disease was coronary artery disease in 21 and idiopathic dilated cardiomyopathy in 4. Six patients had previous coronary artery bypass operations, 1 had undergone repair of an abdominal aneurysm and 1 had pulmonary embolism. Sixteen patients were in New York Heart Association class IV and 9 in class III. Donor mean age was 30 (14 to 46) years. Hospital stay after transplantation was 10 to 90 days (median 11). Four died within 30 days and none from 5 to 59 months (mean 22). The 1-year actuarial survival was 84%. The incidence of rejection was 2.16 episodes per patient. Only 1 patient (4%) had serious infection. Six patients received antihypertensive treatment, 3 had reversible impairment of renal function, 2 had gout and 1 had drop foot. No patient had convulsions, transient ischemic attack or cerebrovascular accident. None had significant psychological problems. The 21 patients currently alive are in New York Heart Association class I. Quality of life, assessed by the Nottingham Health Profile, showed marked improvement. It is concluded that the initial results of cardiac transplantation in the seventh decade of life are encouraging.

Actuarial Analysis

Marital adjustment and behaviour problems in children.

Previous research has suggested links between marital unhappiness and behaviour problems in children. A survey was carried out in a community based Child Psychiatric clinic in Ireland to investigate these links. Methods used involved self report questionnaires administered to mothers of forty-eight children attending the clinic. A control group was selected for comparison. Tests of correlation indicate significant associations between marital adjustment and behaviour problems for both clinic and control populations. Some possible mechanisms are suggested.

Adolescent

A study of emotion and behaviour in children attending a normal school in an urban area.

Anxiety, depression, self-esteem, behavioural deviance and prosocial behaviour were studied in children attending a normal school in a disadvantaged urban area, using self-rated and teacher-rated questionnaires. The prevalence of depression was rated as 5%. 15% described frequent suicidal thoughts. 40% scored as behaviourally deviant. Significant correlations were found between the variables studied. The rates of depression and behavioural deviance were higher than in comparable British populations.

Child