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C Ramsay

Publications and source records attributed to C Ramsay.

9 recordsLinked to original sources
PubMed1990

Oscillometric instrument for the non-invasive detection of low-level microbial activity. Part 2: Growth characteristics, detection limits and impedimetric assays.

Instrument performance and application was evaluated with a variety of microbial suspensions. Data were compared with those obtainable from current commercial apparatus in terms of resolution and detection times. Trials with growing and non-growing cultures indicated periodic synchronous ion exchange processes. Media composition, particularly salt and nutrient ratios, remain crucial to early and rapid detection of viable microbial activity at low concentrations. With appropriate conditions very significant improvements in detection times with typical detection thresholds of 300 min for start concentrations of 10(2) are shown. It is concluded that with regard to resolution and stability, the system out-performs current systems and is superior in terms of potential test costs, sample handling and sample transport.

Asparaginase↗
PubMed1989

Raynaud syndrome in childhood.

Twenty-seven patients with Raynaud syndrome (mean age at onset 11.7 years) were studied to determine the prevalence of primary Raynaud syndrome and to assess the predictive role of antinuclear antibody, nail-fold capillary microscopy, and photoelectric plethysmography in this population. Fourteen patients (52%) had a connective tissue disease, four (15%) had a probable connective tissue disease, and nine (33%) had primary Raynaud syndrome. In all patients with either a connective tissue disease or a probable connective tissue disease, there was a positive reaction to antinuclear antibody, in contrast to patients with primary Raynaud syndrome, in whom antinuclear antibody was not detected. Nail-fold capillary microscopy scores differed significantly between patients with either a connective tissue disease or a probable connective tissue disease and those with primary Raynaud syndrome for both enlarged loop score (p less than 0.025 and less than 0.05, respectively) and avascular score (p less than 0.005 and less than 0.01, respectively). Photoelectric plethysmography scores were reduced in all groups but did not differ significantly between groups. Our findings suggest that in children with Raynaud syndrome, the primary type is more common than was originally suspected, and that both antinuclear antibody and nail-fold capillary microscopy, but not photoelectric plethysmography, can distinguish patients with primary Raynaud syndrome from those with either a connective tissue disease or a probable connective tissue disease.

Adolescent↗
PubMed1987

Cutaneous ultrastructural changes and photosensitivity associated with amiodarone therapy.

Amiodarone, an antiarrhythmic agent, is known to cause photosensitivity and cutaneous hyperpigmentation. Five patients taking this drug for periods of 1 to 48 months were studied. Skin biopsy specimens taken from a sun-exposed site were assessed by light microscopy, electron microscopy, and direct immunofluorescence. Three patients allowed comparative studies to be done on a biopsy specimen from non-sun-exposed skin. Light microscopy findings, including special stains, were not diagnostic of amiodarone-associated cutaneous changes. Electron microscopy, however, displayed distinctive intracytoplasmic inclusions in many cell types, some of which have not been reported previously. These inclusions represent phospholipid membranes associated with amiodarone or its metabolites as the result of a drug-induced lipidosis. Previous reports had postulated the inclusions were lipofuscin. Sun exposure may accelerate the formation of these intracellular deposits because they are more prominent in sun-exposed skin. Four of the above five cases, plus two additional patients, had symptoms compatible with a photosensitivity. Porphyrin assays were normal. Of the six patients phototested, three showed acute reactions to ultraviolet A (UVA) and ultraviolet B (UVB) and significant delayed reactions to UVA and/or UVB. The patients who had normal phototesting were on the drug for shorter periods than those with positive tests.

Adult↗
PubMed1986

Nifedipine in the treatment of idiopathic Raynaud's syndrome.

Thirty-nine patients with idiopathic Raynaud's syndrome were randomized into a double-blind controlled trial comparing nifedipine 10 mg TID to placebo during the winter months between November, 1981 and March, 1983. The pills were doubled at 5 weeks in the absence of subjective improvement. Frequency and severity of vasospastic attacks were recorded in a diary. Over the 10-week treatment period, there was a 48.2% reduction in frequency of attacks in the nifedipine group compared to a 24.6% reduction in the placebo group (p less than 0.05). Treatment reduced the frequency of attacks by at least 30% in 10 of 15 patients. The severity of attacks was also significantly improved. Further, analysis suggests a trend towards diminished effectiveness over time. Side effects occurred in all patients taking nifedipine but were usually mild and well tolerated. Nifedipine is effective in reducing the frequency and severity of vasospastic attacks in idiopathic Raynaud's syndrome over a 10-week period.

Adult↗