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Biomedical subjects

R L Henry

Publications and source records attributed to R L Henry.

At least 145 records · Page 8Linked to original sources
PubMed1983

Liquid-chromatographic quantification of piracetam.

Piracetam, an analog of gamma-aminobutyric acid, absorbs maximally at 197 nm. Its molar absorptivity at 208 nm and pH 4.5 is 3576 (SD 251) L . mol-1 cm-1, approximately 45% of its absorptivity at 197 nm. Direct quantification of piracetam at 197 nm in biological extracts is complicated by the fact that many other compounds absorb between 190 and 220 nm due to carbon-nitrogen bonding. Chromatography of methanol extracts of serum and aqueous humor on a reversed-phase C-18 column developed isocratically with KH2PO4 (0.1 mol/L, pH 4.8) allows detection and quantification of 0.2 mmol of piracetam per liter. Under these conditions the retention time of piracetam is about 5 min. The detector response is linear for quantities between 5 and 15 nmol. The method is rapid, inexpensive, and convenient for the clinical laboratory.

Animals↗
PubMed1982

Erythrocyte - endothelial cell adherence in sickle cell disease, diabetes mellitus, and falciparum malaria: adverse effects reversed with piracetam.

The erythrocytes of patients with sickle hemoglobin, diabetes, and Falciparum malaria adhere disproportionately to endothelial cells. Such pathophysiological activity compromises the microcirculation and results in clinical disease. Since Piracetam (2-oxo-1 pyrrolidine acetamide) has been shown to have a number of clinically beneficial actions on the formed elements of the blood including disengagement of adherent diabetic and sickle erythrocytes there is a rational basis for the trial of Piracetam as an adjuvant drug in SS disease and in diabetes mellitus to improve function of the microcirculation. For similar but somewhat more complex reasons Piracetam may potentiate the efficacy of anti-malarial drugs at any given dosage. Piracetam, a drug known to be safe in a decade of clinical usage, merits serious study in the 3 cited diseases.

Anemia, Sickle Cell↗
PubMed1982

Comparison of peak expiratory flow rate and forced expiratory volume in one second in histamine challenge studies in children.

The difficulty in performing FEV1 in young children prompted us to assess whether PEFR could be used to measure the response to inhaled histamine. In 123 children with recurrent respiratory symptoms we found a highly significant correlation (r = 0.83, P less than 0.001) between the percentage fall from base-line of FEV1 and PEFR. We also performed histamine challenge tests using PEFR alone on 56 children too young to manage spirometry and found our procedure reliable. PEFR is an adequate measurement in histamine provocation studies and can be used interchangeably with FEV1. The criterion for a positive test is a 20% fall in either PEFR or FEV1.

Adolescent↗
PubMed1981

Chlamydia trachomatis and respiratory disease in infants.

Eleven infants under six months of age with respiratory symptoms and positive results of serological tests for Chlamydia trachomatis, including an infant from whom chlamydiae were isolate, are presented. The three distinct patterns of illness in these infants were a bronchitis with paroxysmal coughing, a bronchiolitis syndrome, and a diffuse afebrile pneumonia. We conclude that chlamydial respiratory disease should be considered in Australian infants with the described features. The diagnosis can be confirmed by immuno-fluorescence.

Bronchiolitis, Viral↗
PubMed1981

Antimicrobial therapy in whooping cough.

We compared the ability of erythromycin and co-trimoxazole in clearing Bordetella pertussis from the nasopharynx of 22 children admitted to hospital with whooping cough. Both agents appeared effective. Nevertheless, 10 of the 22 patients gave positive cultures four or more days after antimicrobial administration was begun.

Bordetella pertussis↗
PubMed1981

Polymyalgia rheumatica and giant cell arteritis--rational diagnosis and treatment predicated and disordered prostaglandin metabolism.

We suggest that polymyalgia rheumatica with giant cell arteritis (PR-GCA) is an arachidonic acid metabolites mediated disease which can be diagnosed more accurately and monitored more precisely for therapeutic benefits by the serial determinations of the major urinary prostaglandin F, serum urinary lysozymes, serum acid phosphatase, and serum angiotensin converting enzyme rather than by the erythrocyte sedimentation rate, and, when necessary by temporal artery biopsy. The pathogenetic role proposed for prostaglandins (PG) and, even more precisely perhaps, the leukotrienes in this disease is consistent with the several published clinical observations that non-steroidal anti-inflammatory drug treatment produces in some cases a therapeutic paradox of symptomatic relief with concurrent, if clinically silent, progression of the arteritis, even to blindness. Furthermore, the impressive response of PR-GCA to low maintenance dose steroid therapy, a clinical conundrum for decades, is rationally explained on the basis of depressed or obstructed PG metabolism early on in the metabolic cascade. These views warrant clinical evaluation, confirmation or correction in whole or in part, and may increase our understanding of PR-GCA.

Acid Phosphatase↗
PubMed1981

Cost effective lab service system: better quality medicine at lowered costs.

In this article, the authors describe the Cost Effective Laboratory Service System, a new concept which they explain can reduce hospitalization costs while maintaining or enhancing the quality of medical care. Discussed are the operational features of the system, the development of subsets, prototype trials, and the advantages of and objections to the system.

Cost-Benefit Analysis↗
PubMed1980

A proposed comprehensive pathophysiology of thrombotic thrombocytopenic purpura with implicit novel tests and therapies.

The first detailed comprehensive hypothesis for the pathophysiology of TTP is proposed which accounts for all of the features of TTP at several levels of reference: clinical, physiologic, biochemical, hematologic, and tissue pathology. From the proposed pathophysiology, by deduction, a number of novel diagnostic tests and several rational, promising therapeutic modalities.

Blood Transfusion↗