alpha-Adrenergic blockade with phentolamine significantly enhances the insulin response to arginine. In women phentolamine may inhibit the growth hormone response to arginine. It is suggested that adrenergic mechanisms may act as modulators in hormonal responses to infused amino-acid.

Adult↗

PubMed1966

Use of silicon photovoltaic cells to provide a second channel in flame emission photometry.

Sodium and potassium may be measured simultaneously, using a modified Eppendorf flame photometer. After automatic sampling and dilution of the plasma, the potassium content is measured, using the existing Eppendorf optical and photomultiplier system. The sodium emission is measured by three silicon photovoltaic cells mounted behind an interference filter for sodium, sited on the atomiser casing. The outputs from the photomultiplier and from the silicon cells are recorded by two sensitive recorders. Sixty samples an hour may be estimated, using only 0.12 ml. plasma. Reproducibility tests showed a coefficient of variation of 0.4%.

Photometry↗

PubMed1966

Automated estimation of urinary calcium using the Eppendorf flame photometer.

A method is described for estimating urine calcium on a mechanized Eppendorf flame photometer with twin channels at a rate of 60 per hour. Sodium is estimated simultaneously so that a correction can be made for the small sodium error. Errors due to potassium and phosphate are minimized by adding these ions to the standards and to the diluting fluid. Results agree well with those obtained by Trinder's naphthal-hydroxamic acid precipitation method.

Calcium↗

PubMed1966

Investigation of renal excretion of phosphate and urate.

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Adult↗

PubMed1965

Use and abuse of clinical chemistry in surgery.

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Biochemical Phenomena↗

PubMedDate not supplied

Significance of the hydrogen ion concentration in synovial fluid in rheumatoid arthritis.

The hydrogen ion (H+) concentration and pCO2 were measured in the synovial fluid (SF) from the knee joints of 130 patients with arthritis by an acid-base analyser (ABL2 Acid-Base Laboratory), using a simple technique which prevented contact with air. H+ concentration was significantly higher in SF from 60 RA patients (mean 64.4 n mol/l; range 38-142 n mol/l) compared with patients with OA (mean 44 n mol/l; range 29-56 n mol/l), and 40 with other arthritides (mean 52 n mol/l). The H+ concentration in the SF showed a significant association with other variables of local inflammation-platelet, total leucocyte and polymorph counts, 5-nucleotidase, acid phosphatase and IgA levels in the SF and the clinical knee score, but not with the volume of the effusion. A similar relationship between these variables of inflammatory activity and SF pCO2 was also established. A higher SF H+ concentration was also found in systemically active disease, but no difference in SF pH between seropositive and seronegative patients. Whilst the pH of SF approximated to that of the blood in OA, it was significantly lower in the SF in RA. SF pH is a useful marker of local inflammatory activity, and its measurement is simple, reliable and rapid. It is relevant because changes in pH influence many of the processes involved in inflammation and the pH difference between SF and blood influences the transfer of drugs into the joint.

Arthritis↗