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Biomedical subjects

S Fitzgerald

Publications and source records attributed to S Fitzgerald.

60 records · Page 4Linked to original sources
PubMed1981

The effects of altered cation balance on the fine structure of hypoxic myocardial cells.

To determine whether the changes in intracellular/extracellular cation balance which develop in ischaemic myocardium are responsible for the fine structural changes seen in such tissue, thin slices of normal canine ventricle were incubated under hypoxic conditions at 37 degrees C and physiological pH in balanced salt solution (BSS), isotonic NaCl and isotonic KCl. Slices from each solution were fixed at 10-120 min intervals and examined by light and electron microscopy. For 60 min, tissue from both NaCl and KCl showed good overall preservation of cell architecture and only mild subcellular alterations including aggregation of nuclear chromatin, disappearance of glycogen granules, and swelling of sarcoplasmic reticulum. Tissue from BSS showed early development of intramitochondrial dense inclusions together with focal contraction-band damage similar to that seen in temporarily ischaemic, re-perfused heart muscle and at the margins of infarcts. These changes thus appear to be promoted by divalent cations. The progressive reversal of monovalent cation balance in an area of permanent and severe ischaemia does not appear to be a major determinant of fine structural change.

Animals↗
PubMed1981

The effect of ischaemic injury on the fine structure of canine atrial myocardium.

An experimental model for producing a uniformly and maximally ischaemic segment of atrial myocardium has been devised and used in 23 dogs to investigate the effects of severe ischaemia of up to 6 h duration on the fine structure of atrial myocardial cells. Throughout the first 30 min of ischaemia the cells maintained a fine structure comparable with that of control tissue. In the subsequent 2 h they developed morphological alteration at differing rates, despite their uniform deprivation of blood supply. Even at 90 min the ischaemic tissue showed discontinuous change, with many areas differing little from control, and it was only after 3 h that all cells showed well developed and similar alterations. These included glycogen depletion, marked clumping and margination of nuclear chromatin, and the mitochondrial degeneration typically seen in ischaemically injured ventricle. The changes were very severe after 4 and 6 h of ischaemia, when disruption of cellular membrane systems was also evident. At these times the tissue closely resembled ventricular myocardium made ischaemic for similar intervals, except for the persistence of well-preserved 'specific atrial granules'. Atrial muscle cells therefore develop the fine structural changes associated with ischaemia more slowly than ventricular muscle cells and have a more variable response to the initiation of ischaemic injury.

Animals↗
PubMed1975

Acute subdural hematomas. Review of 144 cases.

The authors report 144 cases in which acute subdural hematomas resulting from closed head injury were surgically treated. The mortality rate was 48% for those treated within 24 hours of injury and 45% for those treated within 72 hours. Patients under 10 years of age had a 33% mortality, while 69% of those over 60 years died. In the first 6 years of the series, 75% of the patients were treated by multiple burr holes and a subtemporal craniectomy, with a mortality of 41% in the last 6 years, 92% of the patients had large craniotomies with a 45% mortality. Of the 32 survivors among the last 60 patients treated, nine require full nursing home care, eight have returned to their own homes, 12 are able to care for themselves but not work, and three have returned to work.

Acute Disease↗
PubMedDate not supplied

Development and consumer validation of the Functional Evaluation in a Wheelchair (FEW) instrument.

PURPOSE: The purpose of the study is to develop an outcome measurement tool to investigate functional performance of consumers using seating and wheelchair systems as their primary seating and mobility device. The instrument is undergoing systematic development in three phases. The results of Phase 1 will be reported. METHOD: Manual and power wheelchair users were interviewed using a modified version of a client-centred outcome measure. An item bank was derived based on the interview data. Subjects were then asked to validate item categories of the new instrument, and finally to self-administer the first version of the instrument. RESULTS: Subjects reported 154 self-care, productivity, and leisure occupational performance issues related to their current seating-mobility system. Based on their input, 10 categories (i.e. transfers, reach, accessing task surfaces, transportation-portability, human-machine interface, architectural barriers, transportation-accessibility, transportation-securement, natural barriers and accessories) were validated for inclusion in the new outcome measure, Functional Evaluation in a Wheelchair (FEW). CONCLUSION: The items on the FEW focus on the interaction between the consumer, the technology, and the milieu. Consumers viewed the overall importance of FEW categories for seating-mobility system users differently than when they self-administered the FEW.

Adult↗