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Biomedical subjects

C Cooper

Publications and source records attributed to C Cooper.

At least 595 records · Page 33Linked to original sources
PubMed1968

The action of digitonin on rat liver mitochondria. Electron microscopy.

1. Rat liver mitochondria were examined in the electron microscope by using negative staining in the presence of 0.3m-sucrose. The intact outer membrane does not appear to be freely permeable to the stain. Where the stain penetrated through a tear it was seen that the inner membrane had randomly oriented grooves, many of which contained round structures varying between 200 and 900å in diameter. Laminar structures containing two to five layers of approx. 50å each were found at the periphery. 2. When the outer membrane was removed by treating the mitochondria with digitonin several types of inner-membrane complexes were formed and they showed a general correlation with those observed in sectioned samples of the same preparations. The main types were: (a) a condensed form looking very much like the intact mitochondrion without the outer membrane (this still showed the grooves, some of which contained the round structures, and the laminar whirls at the edges); (b) a more transparent form containing tubules of uniform width and various lengths (some of these appeared to terminate in a hole at the surface of the inner membrane); (c) a large torn sac, probably the inner membrane, containing some tubules and vesicles. 3. When the inner-membrane complex was further treated with digitonin it was disrupted and the resulting material consisted of pieces of membrane, doughnut-shaped units and lamellar structures. Most of these pieces varied in size between 500 and 1000å.

Animals↗
PubMed1968

The action of digitonin on rat liver mitochondria. Phospholipid content.

1. The amount and types of phospholipid and the fatty acid composition of the various phospholipids were examined in intact rat liver mitochondria, in mitochondria devoid of their outer membrane (preparation A) and in very small pieces derived from the disruption of the inner-membrane complexes (preparation B). The latter two preparations were obtained by digitonin treatment and carry out oxidative phosphorylation. 2. The ratio mug.atoms of phospholipid P/mg. of protein was 0.163 for intact mitochondria, decreased to 0.118 on removal of the outer membrane and increased markedly to 0.292 on disruption of the inner-membrane complex. 3. Examination of the various types of phospholipid present showed that the molar proportions cardiolipin:phosphatidylcholine:phosphatidylethanolamine were approx. 1:6:6 for intact mitochondria and 1:3:3 for preparations A and B. 4. There was a correlation between the recovery of cardiolipin and adenosine triphosphatase activity in the conversion of intact mitochondria into preparations A and B. 5. The fatty acid contents of the various types of phospholipid purified by thin-layer chromatography were identical in all three preparations. Our results show a considerably higher content of arachidonic acid and lower content of oleic acid for phosphatidylcholine, phosphatidylethanolamine and phosphatidylinositol than have previously been reported for mitochondrial phospholipids.

Adenosine Triphosphatases↗
PubMedDate not supplied

Imaging of the liver: a survey update of prevailing techniques for conventional CT scanning.

BACKGROUND: A survey of the Society of Computed Body Tomography/Magnetic Resonance (SCBT/MR) was performed to assess current techniques in liver CT scanning. METHODS: The study was designed as an update to a study performed in 1987. The survey was distributed to 67 members of the SCBT/MR at 35 institutions. RESULTS: Twenty-six institutions responded. As in 1987, none relied solely on noncontrast scans. In 1987, only 54% (12/22) of institutions performed contrast-enhanced scans as their primary technique compared with 73% (19/26) in 1993. Ionic contrast was used exclusively in the earlier study, whereas in the present study 58% used nonionic contrast in the majority of cases and 38% used nonionic contrast routinely. In 1987, 41% performed scans with a power injector compared with 85% in the present study. Enhanced scans were performed during the contrast bolus in 36% of institutions in 1987 compared with 76% in this study. No institution relied on noncontrast scans alone. In the previous study the delay between injection and scanning was variable (0-60 s), whereas in the present study 83% specified a delay of 21-45 s. CONCLUSION: Significant refinements in CT technique, wider use of power injectors, utilization of nonionic contrast, and a more critical approach to optimize liver imaging have created a significant impact on the practice of liver CT.

Angiography↗
PubMedDate not supplied

Cluster scanning in body CT.

Rapid, dynamic computed tomography (CT) is essential in scanning the body in order to maintain adequate contrast enhancement during the entire examination. In the case of the liver, this is most critical in order to complete scanning prior to the equilibrium phase when lesions are less conspicuous or may be missed entirely. This technical note describes the application of "cluster scanning" to conventional scanning in order to optimize body CT by decreasing the total exam time.

Humans↗
PubMedDate not supplied

Computed tomography of the ileocecal region.

The CT scans in 25 patients without ileocecal pathology and 52 patients with ileocecal abnormalities were retrospectively reviewed. The ileocecal region was identified in 18/25 (72%) of patients without pathology. Thirty of 52 patients with ileocecal pathology had inflammatory disease: Crohn's (13), appendicitis (9), abscess (6), and typhlitis (2). CT was complementary to barium studies, demonstrating wall thickening, pericolonic inflammatory change, masses, fascial thickening, and fistulae. Twenty patients had malignancy: primary carcinoma (9), metastases (7), and lymphoma (4). In all patients with carcinoma a mass was identified. Pericolonic stranding represented tumor extension in 5/6 patients. Metastases were identified as extrinsic ileocecal masses in all 7 patients. Liver, mesenteric and omental metastases were present in 8/20 patients. In patients with lymphoma there was wall thickening and two had additional pericecal lymphadenopathy. In 2 patients with hypoalbuminemia, findings included: wall thickening, mesenteric, and subcutaneous edema.

Abscess↗
PubMedDate not supplied

Oral vitamin D3 and calcium for secondary prevention of low-trauma fractures in elderly people (Randomised Evaluation of Calcium Or vitamin D, RECORD): a randomised placebo-controlled trial.

BACKGROUND: Elderly people who have a fracture are at high risk of another. Vitamin D and calcium supplements are often recommended for fracture prevention. We aimed to assess whether vitamin D3 and calcium, either alone or in combination, were effective in prevention of secondary fractures. METHODS: In a factorial-design trial, 5292 people aged 70 years or older (4481 [85%] of whom were women) who were mobile before developing a low-trauma fracture were randomly assigned 800 IU daily oral vitamin D3, 1000 mg calcium, oral vitamin D3 (800 IU per day) combined with calcium (1000 mg per day), or placebo. Participants who were recruited in 21 UK hospitals were followed up for between 24 months and 62 months. Analysis was by intention-to-treat and the primary outcome was new low-energy fractures. FINDINGS: 698 (13%) of 5292 participants had a new low-trauma fracture, 183 (26%) of which were of the hip. The incidence of new, low-trauma fractures did not differ significantly between participants allocated calcium and those who were not (331 [12.6%] of 2617 vs 367 [13.7%] of 2675; hazard ratio (HR) 0.94 [95% CI 0.81-1.09]); between participants allocated vitamin D3 and those who were not (353 [13.3%] of 2649 vs 345 [13.1%] of 2643; 1.02 [0.88-1.19]); or between those allocated combination treatment and those assigned placebo (165 [12.6%] of 1306 vs 179 [13.4%] of 1332; HR for interaction term 1.01 [0.75-1.36]). The groups did not differ in the incidence of all-new fractures, fractures confirmed by radiography, hip fractures, death, number of falls, or quality of life. By 24 months, 2886 (54.5%) of 5292 were still taking tablets, 451 (8.5%) had died, 58 (1.1%) had withdrawn, and 1897 (35.8%) had stopped taking tablets but were still providing data for at least the main outcomes. Compliance with tablets containing calcium was significantly lower (difference: 9.4% [95% CI 6.6-12.2]), partly because of gastrointestinal symptoms. However, potentially serious adverse events were rare and did not differ between groups. INTERPRETATION: The findings do not support routine oral supplementation with calcium and vitamin D3, either alone or in combination, for the prevention of further fractures in previously mobile elderly people.

Accidental Falls↗
PubMedDate not supplied

The effect of temperature on hand function in patients with tremor.

Hand therapists may notice a patient's tremor when treating another diagnostic problem, such as arthritis or a fracture. In these instances, the tremor may become apparent as the patient attempts to don or doff a splint or to practice a home exercise program, or it may be reported in terms of difficulty with dressing or eating. The authors hypothesized that limb cooling would temporarily improve hand function among patients with essential tremor (ET) and that limb warming would temporarily improve hand function among patients with resting tremor secondary to Parkinson disease (PD). Twenty patients with ET and 20 patients with PD completed this single-blind randomized crossover study. Scores following exposure to cold water were compared with scores following exposure to warm water. For patients with ET, subtest scores for the Archimedes spiral, simulated feeding, and checkers were, statistically, significantly lower (i.e., improved) following exposure to cold water than following exposure to warm water; scores for Archimedes spiral card turning, simulated feeding, and checkers were significantly lower following exposure to cold water than at baseline. Scores for Archimedes spiral and card turning were also significantly lower following exposure to warm water than at baseline. For patients with PD, no statistically significant differences were noted between treatments or from baseline except the score for small common objects, which was lower (improved) following exposure to warm water than at baseline. The significant findings from this study support the therapeutic use of cooling to temporarily decrease tremor, thereby improving hand function among patients with ET.

Aged↗
PubMedDate not supplied

Maximizing therapist effectiveness with geriatric hand patients.

The "graying of America" is resulting in higher proportions of older persons utilizing the health care system. Current trends indicate that the geriatric population represents a growing portion of the hand therapy patient population. Appreciating the unique needs of the geriatric hand patient and developing an appropriate treatment program require special interventions that may seem unappealing due to the likelihood of prolonged initial treatment time. However, such steps can strongly enhance therapist effectiveness, patient compliance, and ultimate outcome. The purposes of this paper are: (1) to address frustrations that may be encountered in the treatment of some elderly hand patients; (2) to introduce the reader to the phenomenon of age bias; (3) to present a well-accepted and effective assessment tool of memory, orientation, and ability to follow commands as these competencies pertain to hand therapy; (4) to address concepts in the gerontology literature that can be applied clinically as treatment guidelines to boost treatment effectiveness; and, finally, (5) to suggest communication techniques to use with the elderly hand patient. Maximizing therapist effectiveness with geriatric hand patients will serve to reinforce the dignity and value of this unique population.

Aged↗
PubMedDate not supplied

A review of the autonomic nervous system and exploration of diagnoses associated with reflex sympathetic dystrophy.

The hand therapy literature about reflex sympathetic dystrophy (RSD) tends to discuss this phenomenon in terms of traumatic hand or upper-extremity injury etiology. Hand therapists' bibliographies run the risk of being inbred and delimited to orthopedic and neurologic sources. Nonetheless, this well-developed body of knowledge identifies cardinal signs and symptoms, stages, and clinical types of RSD. Therapy guidelines have been well detailed in accordance with pathophysiologic explanations. The purpose of this article is to provide an overview of the autonomic nervous system (ANS), to briefly consider the history of the term "sympathetic," and to explore familiar and less well-known predisposing events and associated diagnoses. Appreciating the gamut of diagnoses associated with RSD may promote additional opportunities for hand therapist collaboration in the care for this complicated and challenging diagnostic group.

Autonomic Nervous System↗
PubMedDate not supplied

Comparison of the European and USA practice guidelines for Osteoporosis.

The European Foundation for Osteoporosis and Bone Disease (EFFO), the Royal College of Physicians, the European Community and the National Osteoporosis Foundation of the USA (NOF) have recently published guidelines for the diagnosis and management of osteoporosis. All adopt case-finding strategies but the conceptual approach between the European and North American guidelines differs fundamentally. This gives rise to differences in the populations identified for assessment and treatment.

Europe↗
PubMedDate not supplied

Barriers to the use of interpreters in emergency room paediatric consultations.

OBJECTIVE: To identify barriers to the use of trained interpreters in emergency department (ED) paediatric consultations. METHODS: A cross-sectional survey of non-English-speaking-background (NESB) carers who presented a child aged 14 years or less to the Fairfield Hospital ED during a 3-month period was undertaken using a multilingual postal questionnaire or a phone interview with interpreter assistance. RESULTS: Of the 1388 paediatric consultations during the study period, 406 of the carers were registered as being of NESB, with 316 being eligible for study inclusion. Of the 278 (88%) respondents who completed the questionnaires, assistance with interpretation was required by 131 (47%) respondents: 55 (20%) used ad hoc interpreters, 47 (17%) used a trained interpreter and 21 (8%) did not receive the required assistance. Fifty-four (41%) carers who required interpreter assistance were identified as having this requirement at clerical registration in the ED, but only 18 of these were provided with a trained interpreter during the consultation. Limited English proficiency was self-reported by 127 (46%) respondents, with these respondents being more likely to need interpreter assistance (odds ratio (OR) 44.2; 95% CI 21.6-90.7), to have impaired understanding of the consultation (OR 8.2; 95% CI 4.7-14.1) and to consult a language concordant general practitioner (OR 10.1; 95% CI 5.1-19.4) compared with English proficient respondents. CONCLUSIONS: Barriers to the use of interpreters in ED paediatric consultations include poor identification of the need for and provision of an interpreter in the ED, and a preference for NESB carers to use ad hoc interpreters or no interpreter. Recommendations include the implementation in the ED of strategies to improve identification of NESB carers, as well as to improve awareness, access and use of trained interpreters during paediatric consultations. There is also a need to explore the experience of ED staff in accessing and using trained interpreters.

Adolescent↗
PubMedDate not supplied

Computed tomography of omental pathology.

Computed tomographic scans were reviewed in 46 patients with documented omental pathology to analyze the radiographic characteristics of benign and malignant disease. The normal omentum is identified on CT of the abdomen as a homogeneous fat density anterior to the transverse colon. Four distinct patterns of omental pathology were identified: (a) omental caking, (b) finely infiltrated fat with a "smudged" appearance, (c) cystic masses, and (d) discrete nodules. The smudged pattern of omental pathology was identified most frequently; it was present in 20 to 39 patients with malignant disease and in five of seven patients with inflammatory disease. Omental caking was present in 17 of 46 patients but was only identified in malignant disease. Computed tomography provides the most reliable radiographic technique to routinely evaluate omental pathology. A thorough understanding of the variable appearance of omental disease is important in identifying omental pathology.

Adolescent↗