A rapid, sensitive method for accurate analysis of individual bile acids in biological fluids by high performance thin-layer chromatography and densitometry. 1. A rapid new micromethod for quantitative analysis of individual bile acids in duodenal juice by high performance thin-layer chromatography (HPTLC) and densitometry is described and evaluated by comparison with standard TLC and spectrophotometry. 2. Advantages of HPTLC over TLC include more rapid separation, better resolution and more sensitive detection (5 - 10 fold), without the need for prior extraction. Densitometry provides simple, direct and rapid quantitation. 3. The method is accurate and reliable over a range of bile acid concentrations. In the 0.5 mM range, recovery was greater than 89%, and coefficients of variation for within-day analysis were 2 - 12% and for between-day analysis were 6 - 18% for the individual bile acids. Twenty analyses can be performed by one worker in a single day. 4. We conclude that the method offers several advantages over most currently described techniques, is suitable for routine use and is deserving of wider application.


Nanogram-range determination of plasma imipramine by gas-liquid chromatography using a selective nitrogen/phosphorus detector. A sensitive and specific gas chromatographic method for the quantitative determination of plasma concentrations resulting from a single normal therapeutic dose of imipramine has been developed and is descriged. After extraction into a mixture of n-heptane/isoamyl alcohol (98.5:1.5), imipramine is well separated from its main metabolite, desmethylimipramine, and both compounds are detected using a selective detector operating in the N/P mode. The procedure permits the rapid routine quantitative analysis of relatively small plasma volumes (1-2 ml) containing as little as 1-2 ng of imipramine. No interference from the biological matrix is apparent. The suitability of the method for the analysis of biological samples was tested by studying the time of course of imipramine plasma concentrations in normal human volunteers, after administration of a single therapeutic dose.


The contribution of propranolol metabolites to the fluorometric assay of propranolol in human plasma. 1. Studies were undertaken to determine the fluorescent properties of several propranolol metabolites under the conditions of the fluorometric propranolol assay. Of the metabolites studied, propranolol glycol and N-desisopropylpropranolol had significant molar fluorescent coefficients relative to propranolol (72 and 79% respectively). N-desisopropylpropranolol was extracted with the same efficiency as propranolol (greater than 90%) wheras the glycol metabolite had only 34% extraction efficiency. Addition of each metabolite to samples of human plasma containing propranolol produced the predicted increase in fluorescent intensity. 2. Gas chromatographic analysis of plasma collected from 22 hypertensive patients chronically receiving oral propranolol revealed low concentrations of propranolol glycol and N-desisopropylpropranolol relative to propranolol. The results of these studies indicate that fluorescent metabolites of propranolol are not present in sufficient concentration to significantly interfere with the fluorometric assay of propranolol.


Evaluation of continuous solvent extraction of organic acids from biological fluids. We evaluated the efficiency of continuous solvent extraction with ether for the analysis of organic acids by gas chromatography using a representative group of organic acids and urine from several normal children. Variables examined were the time of extraction, volume of sample, and the quantity and chemical class of acid present. In terms of the decreased time required and invariant extraction of acids of pathologic significnace continuous solvent extraction compares favorably with the more time consuming albeit less discriminatory ion-exchange procedure. Continuous solvent extraction appears especially well suited for analysis of short chain aliphatic acids by gas chromatography.


Interferences in an emergency acetaminophen method and its modification. A quick simple method for emergency acetaminophen estimation is that of Glynn and Kendall (1975). Apart from the known interference of salicylate, sera from uremic patients was shown to give falsely high results. A modified method is presented, with a scanning check to identify the presence of such non-specific chromogens.


Effect of specimen storage and preservation on toxicological analyses of urine. 1. The stability of nineteen classes of drugs or their metabolites in urine specimens, for the purpose of toxicological screening has been studied for periods of up to thirty-six weeks. 2. The effect of specimen preservation by refrigation and by the addition of boric acid, chloroform, sodium fluoride, mercuric chloride, and buffers, has been assessed. 3. With the exception of flurazepam, glutethimide, and secobarbital, specimens may be retained at room temperature for periods in excess of six weeks without deterioration. 4. Preservation by the addition of sodium fluoride (5 g/l) followed by freezing, thawing, and filtration significantly prevents specimen deterioration, and may be used as the method of choice.


A computer model in the selection of multiple channel analysers. 1. A simple computer model is described which was used to study possible test combinations on automated multichannel analysers. Specific objectives were minimisation of manpower and maximisation of throughput of the specimen preparation process. 2. In our case, by appropriate test combination selection, a staff saving of 50% in the aliquotting process is predicted. For tests that are available on multichannel analysers, a reduction from 198 to 121 aliquots per 100 patient specimens is expected on an 18 channel machine. With the use of filter separation systems, manual aliquotting would be required for 21 specimens per 100.


A convenient method for the determination of non-specific binding in commercially available solid phase iodine labeled radioimmunoassay kits. 57Co-cyanocobalamin is substituted for iodine labeled antigen in three commercially available solid phase radioimmunoassay kits to evaluate the extent of non-specific binding by determination of the supernatant and residual fraction of unbound ligand and thus obtain a value for corrected binding throughout the range of the calibrated standard curve. In the present state of technology correction appears to have a trifling effect on the overall accuracy of the assay; however, the method as described allows the laboratorian to confirm for himself when testing a new product.


Micro-scale extractive alkylation procedure for the gas-chromatographic measurement of theophylline in serum and saliva, with use of a nitrogen detector. In this 10-min gas-chromatographic assay for theophylline, a 25-microliter portion of serum or saliva sample, 100 microliter of extraction reagent, and 1.0 ml of solvent were mixed, the solvent separated and evaporated, and an aliquot of the reconstituted extract injected into the gas chromatograph. At a concentration of 11 mg/liter, within-run precision (CV) was 3.6% and run-to-run 2.9%. At 22 mg/liter, within-run precision was 2.8%. Concentration and instrument response are linearly related between 2 and 40 mg/liter. The limit of detection was 0.4 mg/liter. Results correlated well (r = 0.98) with those by another micro-scale gas-chromatographic procedure. Analytical recovery was estimated to exceed 90%, and no interferences from other xanthines or related drugs were observed.


Adrenal status assessed by direct radioimmunoassay of cortisol in whole saliva or parotid saliva. We describe a direct radioimmunoassay for cortisol in 10-microliter volumes of parotid saliva or whole saliva. Binding proteins are absent from these fluids, as demonstrated by the excellent correlation between results for samples assayed directly and by a comparison procedure involving extraction with 1,2-dichloroethane. The direct assay is specific, precise, and had a lower limit of sensitivity of 4 pg per assay tube. Comparison of cortisol concentrations in plasma, parotid saliva, and whole saliva in persons undergoing investigations for assessing adrenal function, including stimulation with cosyntropin (Synacthen) and suppression with dexamethasone, indicated that changes in plasma cortisol concentration were accurately and immediately reflected in saliva from either the parotidgland or whole saliva. A marked circadian rhythm has also been demonstrated for cortisol in parotid-gland saliva and whole saliva. We had to modify the 1,2-dichloroethane extraction procedure for accurate determination of cortisol in parotid saliva and whole saliva of patients undergoing treatment with metyrapone.


Simple radioimmunoassay of cortisol in diluted samples of human plasma. We describe a simple radioimmunoassay of plasma cortisol, which can be performed in 3 h and which requires no purification, heating, or refrigeration steps. The plasma proteins are inhibited through direct competition between them and the antiserum at room temperature, at which the antiserum's affinity exceeds that of the binding proteins. Plasma, diluted with water, is incubated for 3 h at room temperature with [3H]cortisol and the antiserum. We compared results with those by the usual extraction method. The correlation between methods on evaluating normal samples with one antiserum. We compared results with those by the usual extraction method. The correlation between methods on evaluating normal samples with one antiserum was r = 0.954 (P less than 0.001), and the slope was 0.661. With three other antisera it was r = 0.922 (P less than 0.001) and slope 0.644. Plasmas with abnormal protein concentrations (i.e., from preganant women, and after corticotropin administration), tested to examine the validity of the method for routine use, and to define the role of the protein carriers, showed r = 0.859 (P less than 0.001) and slope 0.726 for the four antisera used. Additional samples, assayed with diluted standards plus stripped plasma, showed a correlation with the usual extraction method of r = 0.945 (P less than 0.001) and slope 1.026.


Radioimmunoassay of methaqualone in human urine compared with chromatographic methods. The 125I-radioimmunoassay for methaqualone in human urine was evaluated by a comparison with newly modified gas-liquid chromatographic and thin-layer chromatographic methods. The statistically significant sensitivity value for the radioimmunoassay was at 2 microgram of methaqualone per liter of urine. The coefficient of variation was 2.88 +/- 0.39% interassay and 2.71 +/- 0.16% intraassay. There was cross-reactivity only with metabolites of methaqualone, 4'-hydroxymethaqualone being twice as sensitively measured as methaqualone. There was complete agreement between results by radioimmunoassay and by gas-liquid chromatography in 96.7% of the samples analyzed. Only 1.2% of the radioimmunoassay values were false positives, and 2.1% false negatives (phi = 0.8917, P less than 0.001). Comparisons between the thin-layer chromatographic data and the gas-liquid chromatographic or radioimmunoassay data showed less agreement because of the 50- to 200-fold higher sensitivity of the latter two techniques. Gas-liquid chromatography therefore appears to represent the best reference method for the evaluation of the radioimmunoassay, which appears to be a very sensitive and reliable technique for detecting methaqualone and its metabolites in human urine.


External quality-control survey of cholesterol analyses performed by 12 lipid research clinics. We report accuracy and precision achieved in the automated analysis for cholesterol in a long-term multilaboratory study, presenting and evaluating the significance of data accumulated by 12 Lipid Research Clinics (LRC's) in the analysis of 18 unknown surveillance pools during three years. The average bias for all pools and for 13 autoAnalyzer II (Technicon Instruments Corp., Tarrytown, N.Y. 10591) instruments in the 12 clinics was -0.41% (range -1.2 to +0.3%), as compared to values established by reference methodology. The regression equation relating observed cholesterol values (y) to reference values (x) was: y = 0.35 + 0.977x. The bias varied from pool to pool (-2.3 to +5.3%), positive biases being observed for pools with cholesterol concentrations less than 1.4 g/liter, and negative biases for those pools with higher concentrations. Total standard deviations ranged between 25 and 75 mg/liter, and total CV's for most individual instruments were between 1 and 3%. Of the variability for a particular pool, less than 20% was due to differences among instruments, and within- and between-run variabilities were approximately equal. These trends were the same as those previously observed [Clin. Chem. 23, 1744 (1977)] in the analysis of bench control pools of known cholesterol concentration.


Determination of aluminum in biological samples by atomic absorption spectrophotometry with a graphite furnace. Aluminum, generally considered non-essential and non-toxic, may accumulate in toxic amounts in the brain in cases of chronic renal failure. We describe a procedure for its analysis in biological fluids by atomic absorption spectrophotometry with a graphite furnace. No sample preparation is required and the procedure is sensitive at the appropriate concentrations. A sample of serum or urine is pipetted into the interior of the graphite tube, where it is sequentially dried, charred, and atomized. Precautions for sample handling are discussed and instrument settings are defined. Precision and accuracy of the method are evaluated, as are the effects of salts, protein content of serum, and specific gravity of urine. Serum of 23 persons who were not consuming aluminum-containing antacids contained 28 +/- 9 (SD) microgram of Al per liter (1.02 +/- 0.33 mumol/liter).


Bilirubin-protein interactions monitored by difference spectroscopy. Difference spectroscopy is used to monitor bilirubin-protein interactions, to assess the residual binding capacity of proteins for bilirubin. A change in the difference spectra monitored at 482 nm is directly proportional to bound bilirubin up to a molar ratio of bilirubin to albumin of approximately 1; increasing bilirubin beyond the 1:1 molar ratio does not further change the difference spectra. After excess free bilirubin is added, the change in the difference spectrum is proportional to the residual binding capacity of the serum for bilirubin. The risk of kernicterus among neonates may be assessed by monitoring the residual bilirubin binding capacity of serum. This report summarizes our research effort leading to an assay method which requires only 40 microliter of serum and can be completed in less than 10 min.


Spectrodensitometry of nanogram quantities of cholesterol. In studies of hydrolysis and synthesis of cholesterol esters by aortic enzymes, conventional methods (aside from isotope methodology) are too insensitive to measure reaction products when few aortas are used. High-performance thin-layer chromatography coupled with spectrodensitometry of plates charred after spraying with a cupric acetate-phosphoric acid reagent permitted quantitation of 10-ng amounts of cholesterol, cholesterol oleate oleate, and oleic acid. Linear calibration curves were obtained after spectrodensitometry of chromatograms containing 10-200 ng of lipid. The results were verified by radioassay.


Liquid-chromatographic determination of serotonin in serum and plasma. Using high-performance liquid chromatography with electrochemical detection, we determined serotonin in plasma from parkinsonian patients being treated with L-3,4-dihydroxyphenylalanine or N-(DL-seryl)-N'(2,3,4-trihydroxybenzyl)hydrochloride plus L-3,4-dihydroxyphenylalanine ("Sinemet") and in serum from a blood bank, from "normal" persons, and a pooled specimen from a hospital clinical laboratory. The values obtained for the two groups of Parkinson's disease patients showed no significant difference. Long-term storage on solid CO2 was xhown to be an adequate technique for preserving samples. The mean (+/-SEAM) normal value obtained for serotonin in serum was 146 +/- 46 microgram/liter (n = 23), a result in harmony with that previously obtained [Clin. Chem. 20, 812 (1974)] by fluorometry. In comparison to other methods for measurement of serotonin in serum or plasma, we believe that the present scheme offers greater selectivity, sensitivity, and precision.


Fluorometric determination of erythrocyte protoporphyrin in blood, a comparison between direct (hematofluorometric) and indirect (extraction) methods. We measured the concentration of erythrocyte protoporphyrin in 43 blood samples by two fluorometric methods. In the indirect method, protoporphyrin was extracted from blood and the fluorescence of the free acid in the extract was determined with a filter-fluorometer. These results were compared with results of direct determination of protoporphyrin in the same samples. In the direct assay the fluorescence of protoporphyrin, present in blood as the zinc salt, was measured without extraction, with the use of a hematofluorometer. Comparison of the results of the direct and indirect methods showed an excellent correlation (r = 0.986), but the hematofluorometric values (y) were approximately 9% lower than the fluorometric values (y = 0.911x). The slope of the regression line (0.911) is likely to be different for each hematofluorometer-fluorometer combination. Therefore, hematofluorometric values can only be compared with fluorometric values if the slope of the regression line is known and is used as a correction factor.


Clinical analysis of tamoxifen, an anti-neoplastic agent, in plasma. Tamoxifen, a phenylstilbene derivative, is currently being used to treat metastatic breast cancer. We describe an analytical method for monitoring the parent drug and its 4-hydroxylated derivative in whole blood and plasma. After extraction from biological media, the analytes are converted to highly fluorescent products by ultraviolet irradiation, and then separated by liquid-chromatography on a muBondapak CN column, with spectrofluorometric detection of components. Detection limits for tamoxifen and its 4-hydroxy derivative are 1 and 2 microgram/liter of biological fluid, respectively. Conditions have been optimized so that the reaction proceeds fast enough for convenient sample handling without jeopardizing fluorescence yield due to the photocatalyzed degradation of the fluorescent product. Evidence suggests that the fluorophore being monitored is a phenanthrene derivative.


Selective purification of tartrate-inhibitable acid phosphatases: rapid and efficient purification (to homogeneity) of human and canine prostatic acid phosphatases. We describe the synthesis of a long-chain monoamide derivative of L(+)-tartaric acid and its attachment to Sepharose 4B. Procedures are then described for use of this material in purifying human prostatic and (for the first time) canine prostatic acid phosphatases to constant specific activity and electrophoretic homogeneity. Depending on sample size, such purification is possible in one step, and is clearly faster and more efficient than are previously described methods. These materials and procedures have significant potential in studies of the comparative biochemistry and clinical chemistry of tartrateinhibitable acid phosphatases.


Direct non-chromatographic radioimmunoassay of aldosterone: validation of a commercially available kit and observations on age-related changes in concentrations in plasma. Human plasma aldosterone can be rapidly, directly, and reliably measured by radioimmunoassay with use of a commercially available anti-aldosterone antibody. With this method, we show that values tend to decrease with advancing age, especially after the sixth decade.


Comparison of three radioligands, selenium-75, lodine-125, and tritium, in the radioimmunoassay of methotrexate. Radioimmunoassays for methotrexate are described, involving use of a rabbit antiserum to a conjugate of the drug and bovine serum albumin and the drug labeled with tritium, selenium-75, or iodine-125. Of the two gamma emitters, the 75Se-labeled drug was prepared by the Radiochemical Centre, Amersham, England and the 125I-labeled drug in the laboratory, by the Chloramine T iodination technique. The stability of labels with both methods allows use of the faster, cheaper, and simpler gamma-counting techniques, with results available after 3 h. All three methods have acceptable sensitivity, accuracy, precision, and reproducibility, and are specific for methotrexate, with no significant interference from naturally occurring folates or leucovorin. The assays in which the gamma emitters are used have significant practical advantages over the beta emitter and are much better suited to automation and clinical application. The main advantage of 75Se=labeled methotrexate is its longer half-life, 121 days, as compared with 60 days for 125I.


Analysis for salicylic acid in serum by high-performance liquid chromatography. We report a specific and sensitive quantitative assay for salicylate in serum or plasma. As little as 3 microliter of sample can be analyzed by an external standard procedure and larger volumes by diluting with the internal standard (o-methoxybenzoic acid). No extraction or derivatization is necessary and salicylic acid and the internal standard elute in 6 and 3.75 min, respectively. Peak-height ratios are linearly related to concentrations between 10 and 500 mg/liter. By comparison with an existing fluorometric method, our procedure is faster, more specific, and more sensitive.


Plasma calcium, copper, magnesium, and zinc concentrations in patients with the alcohol withdrawal syndrome. We determined zinc, copper, magnesium, and calcium concentrations by atomic absorption spectrophotometry in the plasma of 30 patients hospitalized for treatment of seizures during a period of alcohol withdrawal. Those patients who developed delirium tremens or a prolonged hallucinatory state had significantly higher plasma copper concentrations (P = 0.026), significantly lower zinc concentrations (P = 0.004), and significantly higher copper/zinc ratios (P = 0.001) than the patients who recovered uneventfully. Zinc deficiency may be one of the factors that contribute to the neurologic complications of alcoholism. A determination of the plasma copper/zinc ratio early in the course of alcohol withdrawal could be of value in indicating which patients have the most substantial underlying disease or metabolic imbalance and therefore may be at greatest risk of developing delirium tremens or prolonged hallucinosis.


Creatine kinase in serum: 5. Effect of thiols on isoenzyme activity during storage at various temperatures. We studied changes in the activity of human creatine kinase isoenzymes (native MM in serum, MM, MB, and BB preparations in serum matrix) on storage in the presence of 0, 10, 20, and 50 mmol of N-acetyl cysteine, 2-mercaptoethanol, and 1-thioglycerol per liter of serum at 37, 30, 25, 4, and -20 degrees C. We also assessed the stability of the thiols under the same conditions. We generally confirmed increasing stability in the sequence: BB, MB, and MM isoenzyme. Above 30 degrees C irreversible inactivation is very rapid, even in the presence of thiols. At lower temperatures endogenous MM is sufficiently stable; thus, the use of protective thiols can be restricted to sera expected to contain isoenzymes MB or BB. Our studies lead us to prefer use of 50 mmol of N-acetyl cysteine per liter of serum. The other thiols cause turbidity to develop earlier and their decomposittion products diminish the activity more. The initial activity of the MB and BB preparations increased by as much as 2.3- and 1.8-fold on storage with thiols. This effect was not observed with either endogenous MB and MM or with the MM prepartion.


Emergency procedure for digoxin radioassay. A rapid but precise radioassay for digoxin has been developed by optimizing the conditions for antigen-antibody interaction and for separation of bound and free fractions. This new procedure involves incubation of radioactively labeled antigen, antibody, and standard or sample at 3 degrees C for 10 min. Charcoal is then added, the mixture centrifuged for 5 min, and the radioactivity of the supernate counted. Results are available in less than 1 h after receipt of the specimens, making the procedure suitable for emergency determinations. Results correlate well with those by our routine procedure (Becton Dickinson) (r = 0.9739, y = 0.0356 + 0.9915x, n = 49). Analytical recovery of added pure digoxin exceeds 94%, both within and between assay CV's are less than 8%.


Blood intermediary metabolite and insulin concentrations after an overnight fast: reference ranges for adults, and interrelations. Concentrations of several metabolites in deproteinized blood and plasma were determined in 100 subjects after an overnight fast, to establish reference ranges. Blood glycerol, nonesterified fatty acids, and ketone body concentrations and the 3-hydroxybutyrate/acetoacetate ratio increased with age while blood alanine concentrations delined. Serum insulin and blood alanine concentrations were also related to weight. No marked sex-related differences were found, although blood glycerol concentration was slightly higher in women. Distribution of all metabolite concentrations was positively skewed, except for glucose, but skewness could be corrected by logarithmic transformation. Skew was particularly marked for blood ketone body concentrations. Concentrations of all metabolites in plasma exceeded those in whole blood, but this was significant for only lactate and pyruvate when concentrations in plasma were compared with calculated concentrations in erythrocyte water.


Gas-liquid chromatographic determination of bupivacaine and lidocaine in plasma. A modified gas-liquid chromatographic method for determining plasma concentrations of bupivacaine and lidocaine is described, with cyclizine as an internal standard. The extraction procedure requires no solvent evaporation, thus overcoming the problem of drug volatility. Concentrations as low as 0.1 mg/liter can be determined. The plasma sample is made alkaline and extracted into n-hexane, re-extracted into a small volume of an aqueous acid phase, and finally extracted into 50 microliter of methylene chloride after alkalinization. The final extract is assayed by gas chromatography on a 5% OV-17 column. The extraction scheme of the present method eliminates interferences by endogenous plasma constituents.


Improved thin-layer chromatographic method in the diagnosis of mannosidosis. An improved thin-layer chromatographic method is described for the facile separation of neutral oligosaccharides excreted in the urine of patients with mannosidosis. The urine sample is treated with mixed-bed ion-exchange resin to remove charged species. The eluate is then chromatographed on silica gel thin-layer plates with n-propanol water as the developer. Eleven unique orcinol-positive components can thus be resolved. The advantages of this method over previously described techniques are the ease and rapidity of assay, better resolution of components, and clarity of resolution. It should be applicable to other disease states in which distinctive neutral carbohydrate products are produced.


New continuous-flow analysis for simultaneous determination of creatinine and uric acid in 200 microliters of serum without use of a dialyzer. We present a new method for direct continuous-flow (AutoAnalyzer II) measurement of serum creatinine and uric acid. The manifold is simple, inexpensive, and can be constructed in the laboratory. Only 200 microliters of serum is needed; analysis rate is 60 samples per hour. The incorporation of sodium dodecyl sulfate and the simultaneous provision of blank subtraction make it possible to omit the dialysis step. Our method does not require the linearizer, since instrument response and concentration of creatinine and uric acid are linearly related to 200 and 120 mg/liter, respectively. The percentages of steady state, interaction, and recovery are acceptable, Precision is excellent and the results obtained from the new method correlate well with those obtained by the comparison methods. Interferences are few and, when encountered, are generally smaller than in the modified Technicon method. Marked hemolysis interferes only with the uric acid assay; marked turbidity has no effect on results for creatinine. Icteric serum with total bilirubin of 50 and 100 mg/liter interferes significantly with results for creatinine and uric acid, respectively, by the new method.


Direct solid-phase 125I radioimmunoassay of serum cortisol. We report a solid-phase iodine- 125 radioimmunoassay for serum cortisol in which the interfering binding proteins are inactivated by a combination of reaction pH and 8-anilino-1-naphthalenesulfonic acid. The procedure is easy to perform and gives accurate and reliable results. The shift in pH for optimum binding of an antibody resulting from immobilization on a solid support, used to decrease cortisol binding competition in the present test, is potentially exploitable in other antibody and enzyme systems.


Measurement of chloroprocaine and procaine in plasma by flame ionization gas-liquid chromatography. We describe an isothermal gas-liquid chromatographic procedure developed for measuring procaine and chloroprocaine in plasma. The unchanged drug is extracted into toluene from alkalinized plasma, together with an internal standard. The solvent is removed, the residue redissolved in methanol, and aliquots are injected into a 91.5-cm gas-liquid chromatographic column containing 3% OV-210. Sensitivity of detection is in the nanogram range.


Use of the vertical rotor to facilitate estrogen and progesterone receptor analysis. Sucrose density-gradient analysis is one method of identifying specific estrogen and progesterone receptors in mammary tumor tissue. Use of the vertical rotor makes this practical for routine applications in the clinical laboratory by increasing the number of samples that can be run at one time and shortening the centrifuge time from 18 to less than 2 h. The separations and reproducibility compare favorably with those obtained with a swinging-bucket rotor.


An impurity in the buffer 2-amino-2-methyl-1-propanol, which correlates with depression of measured alkaline phosphatase activity. Recent findings indicate that the buffer 2-amino-2-methyl-1-propanol, widely used in clinical measurement of alkaline phosphatase activity, contains an impurity that inhibits the activity of the enzyme. Analysis of several lots of 2-amino-2-methyl-1-propanol has demonstrated the presence of a material, the concentration of which correlates well with alkaline phosphatase activity. Mass spectral analysis of this material indicates that it is a substituted ethylenediamine compound. Zinc chelation is discussed as a possible mode of its inhibition. Further work is in progress to separate and characterize this and other compounds in the buffer and to determine their modes and degrees of alkaline phosphatase inhibition.


Semi-automated micro-scale extraction apparatus for assay of free fatty acids in plasma. We describe the use of a semi-automated micro-scale extraction apparatus as applied to the assay of free fatty acids in plasma. With it, a smaller plasma sample is required, disposable glassware can replace acid-washed glassware, and the number of samples that one technican can assay per day is increased fivefold. Theroretically, this apparatus can be applied to all assay procedures requiring one or more extraction steps.


Enzymic serum cholesterol measurement with a basic autoanalyzer and Du Pont aca method. I compared enzymic methods for total serum cholesterol as used with discrete (Du Pont aca and reagent packs) and continuous-flow (Boehringer Mannheim reagents and the Technicon AuotAnalyzer I) analysis of normal, icteric, and lipemic sera. The regression equation for 24 clear, non-icteric sera was: y (continuous flow) = 0.944x (aca) + 10.69; r = 0.971, Syx +/- 53.7 mg of cholesterol per liter. The continuous-flow system indicated no significant interference when as much as 350 mg of bilirubin was added per liter. Results with the aca method indicated a decrease in apparent cholesterol of about 5 mg/liter per milligram of added bilirubin. Serial diluting of lipemic sera resulted in falsely higher values with the aca method but no clinically significant effect on results with the AutoAnalyzer procedure. Apparent cholesterol as measured with the aca became proportionately greater than AutoAnalyzer values with increasing serum triglyceride concentration.


Detection of hemophilia A carriers by use of frozen plasma samples. The efficacy of using promptly frozen plasma samples in the diagnosis of the carrier state for hemophilia A was evaluated by simultaneous measurement of factor VIII acitivity and antigen in 20 normal women and 20 obligate carriers. Factor VIII antigen was measured by two methods, electroimmunoassay and immunoradiometric assay. When the factor VIII activity and antigen data were evaluated by regression analysis, 94% of the carriers were correctly identified at the 95% confidence level.


Emergency gas-chromatographic assay of phenobarbital and phenytoin and liquid-chromatographic assay of theophylline. Phenobarbital and phenytoin are extracted and concentrated in a single step, without solvent evaporation, followed by on-column methylation and gas-chromatographic quanitation. A similar extraction step for the assay of theophylline by high-pressure liquid chromatography is described. The extraction step can be completed in less than 2 min, the chromatographic step in less than 8 min. This extraction method yields clean chromatograms, avoids evaporating health-hazardous solvents, and is applicable to other drugs.


Performance comparison of the Corning thin-film agarose and the Hyland thick-film agar methods for immunoelectrophoresis. Many clinical laboratories do immunoelectrophoresis for qualitative assessment of proteins in biological fluids. Commercial kits are available that supply some or all of the necessary components, but the nature of these components varies. Seeking a reliable method for most easily preserving the original immunoelectrophoresis pattern as a permanent record, we compared a thick-film agar method to a thin-film agarose method in immunoelectrophoresis of a total of 70 serum and urine samples. For each sample, either method resulted in the same interpretation. The thin-film agarose method not only yields a stained, permanent record in about the same time that the thick film agar is ready for interpretation but not preservation, but also requires less antiserum, a smaller sample, and may not require purchase of additional hardware.


Emergency determination of acetaminophen. I describe a senstive colorimetric micromethod in which a pH 11.0 carbonate buffer is used to induce acetaminophen to react with Folin-Ciocalteau reagent at room temperature. These reagents and a simple solvent extraction favor formation of a stable indophenol dye with acetaminophen, giving this procedure a good degree of specificity. Results correlate well with those by liquid-chromatographic procedures, and day-to-day precision is less than 8%.


Endocrine effects of alcohol.

Endocrine effects of alcohol. A variety of effects of alcohol on endocrine function are now well documented. Clinically, the most important of these are alcohol-induced 'pseudo-Cushing's syndrome' and a syndrome of hypothalamic-pituitary-adrenocortical unresponsiveness, both of which result from long-term over-indulgence, and impairment of testosterone secretion which may occur following relatively short-term drinking. Evidence indicates that a number of different mechanisms are responsible for mediating the effects of alcohol on endocrine function. In a few instances (e.g. inhibition of vasopressin secretion and impairment of steroidogenesis resulting in a fall in testosterone production rate), alcohol appears to influence directly the release or synthesis of individual hormones. However, the majority of the endocrine effects of alcohol are probably indirect, resulting from either the stress of intoxication (stimulation of cortisol, catecholamines and possibly GH and prolactin), changes in the level of intermediary metabolites (e.g. a fall in circulating FFA stimulating GH secretion) or changes in the metabolism of hormones (e.g. catecholamines, oestrogens, androgens) resulting from alteration in intracellular redox state or tissue damage.


Alcohol and nutrition.

Alcohol and nutrition. Alcoholic patients frequently have evidence of nutritional deficiency the consequences of which may be seen in all systems of the body. Alcoholism is theoretically a completely preventable disorder which requires more attention by the general public, practising physicians and research workers. Rehabilitation of the established alcoholic will sometimes be limited by failure to modify behaviour or because of nutritionally induced brain damage but we are beginning to understand some of the mechanisms by which malnutrition evolves (Figure 2). Better methods must be developed to limit alcohol-induced tissue injury in patients whose drinking cannot be controlled. The final mechanisms of liver injury remain to be established. Cirrhosis may be induced in animals ingesting a good diet but this does not ensure adequate delivery and utilization of nutrients at the subcellular level. Cirrhosis takes a long time to evolve and the natural history, including longitudinal nutritional profiles in man, has not been established. Therefore, although normal liver morphology is sometimes seen in alcoholics with gross stigmata of malnutrition suggesting that factors other than malnutrition are important, it may be that critical nutrients have not been deficient for long enough in these individuals or severe depletion has been intermittent. Whether or not malnutrition is of decisive importance in the toxicity of alcoholic liver injury in man, adequate replacement is essential for protection and repair of liver cells. Established daily minimal requirements are not adequate for patients with active liver disease. Hepatocyte injury reduces the capacity of this major storage site and causes release of vitamins (co-enzymes) into the circulation in the form of holoenzymes. Liver damage reduces the conversion of nutrients into their metabolically useful forms required for catabolic processes and to meet increased needs for DNA/RNA synthesis necessary for repair of damaged cells and to replace necrotic cells. The choice and route of therapy must take account of the patient's metabolic needs and their absorptive defects. The effects of alcohol and maternal undernutrition on the fetus/neonate may cause intra-uterine death or varying degrees of brain damage, thus limiting the potential of the next generation.


Mosaicism and the trisomy 8 syndrome.

Mosaicism and the trisomy 8 syndrome. Three new cases of trisomy 8 mosaicism are presented; two have features corresponding with those usually found in this syndrome, whereas one is highly atypical. In view of the almost universal mosaicism of these patients, the literature is reviewed with an emphasis on the patterns of mosaicism found. There is little correlation between degree of mosaicism and extent of clinical abnormality. The degree of mosaicism differs in different tissues, fibroblasts being more informative of aneuploidy than lymphocytes, and there is some evidence that the degree of mosaicism varies with time. The reasons for these findings are discussed, with particular reference to the raised paternal age found in a proportion of the reported cases.


In vitro studies of the interaction of calcium ions and other divalent cations with the Lp(a) lipoprotein and other isolated serum lipoproteins. The interaction of isolated Lp(a) lipoprotein with different divalent cations was studied and compared to that of other isolated lipoprotein classes. Purified Lp(a) lipoprotein was found to be most sensitive to the metal ions tested, and the Lp(a) lipoprotein was the only lipoprotein which was precipitated by calcium ions alone. The precipitation apparently depends on the ionic radii of the cations used as well as on the lipoprotein class tested. The precipitation reaction between calcium ions and the Lp(a) lipoprotein, and the interaction between calcium ions and LDL (without precipitation) seem to follow the known rules for small ion-macromolecule interaction reasonably well. The calcium ion - Lp(a) lipoprotein interaction results in a small aggregate. The binding is of ionic type and the precipitation reaction is initially reversible. It was estimated that LDL particles have a mean of 290 equivalent and non-interacting binding sites for calcium ions. The above observations concerning the Lp(a) lipoprotein may be of interest in view of the significantly higher frequency of early coronary heart disease in Lp(a+) than in Lp(a-) individuals, and in view of the previously reported biochemical differences between individuals of different Lp phenotype.


Expression of "adult" polycystic renal disease in the fetus and newborn. The manifestations of "adult" polycystic disease of the kidneys are reported in fetal life and during infancy. At the time of diagnosis, the patients in whom the disorder was detected were a stillborn fetus, a liveborn baby immediately after birth, a neonate at 3 weeks of age, and three infants between 2 1/2 and 4 months of life. In all six cases, who were unrelated, similar implication of other family members was elicited, and in four, parental disease was documented. As expected, the disorder in these families was transmitted in an autosomal dominant fashion. Apart from the youngsters reported here, all the other known patients in the respective families were of adult age. The disease was fatal in all of our patients, with death ensuing (except, of course, in the stillbirth) from hours to weeks after the diagnosis. This report underlines the variability in the age of expression and the mode of presentation of "adult" polycystic kidney disease.


Cluster of cystic fibrosis cases in a limited area of Brittany (France). Cystic fibrosis in the northern sector of the French "département" of Finistère is 1:1787 live births. Within this sector a concentration of the disease was found in a small area. The minimal frequency in this area, from 1946 to 1972, was calculated as 1 per 377 live births, the gene frequency being 0.0515. Genealogic analysis, going back to the beginning of the 18th century, showed a relationship between 8 of the 10 families to which the patients belonged. The origin of the deleterious genes may be explained by a least five primary ancestral couples living in the 18th century. Random drift is the most probable explanation for the concentration of cystic fibrosis in this region.


Influence of continuous-flow blood separator leucophoresis on in vitro functions of human lymphocytes. The influence of continuous-flow blood separator leucophoresis on these in vitro functions of human lymphocytes was studied. In ten separation experiments, lymphocyte functions were examined in the presence and absence of mononuclear phagocytes before, during and at the end of continuous flow leucophoresis. Cell surface markers and effector functions in spontaneous cell-mediated cytotoxicity (SCMC) and antibody-dependent cellular cytotoxicity (ADCC) assays did not change significantly under the conditions of leucophoresis. By contrast, separator lymphocytes exhibited a significantly increased mitogenic response to pokeweed mitogen and PPD. Removal of mononuclear phagocytes corrected for this phenomenon. PHA and Con A responses were not affected by leucophoresis, nor was the number of circulating haemopoietic stem cells (CFU-C) significantly altered during a 4 hr continuous flow blood separator run.


Immune complexes in peripheral blood polymorphonuclear leucocytes of malignant melanoma patients. Immune complexes in PMN cells of sixty-five patients with malignant melanoma were studied by scoring the cells for IgG and complement inclusions. Group (a), consisting of thirty-four patients free from tumour after surgical therapy, showed a median IgG score of 17, which was not statistically different from the control group (n = 11), with a median score of 10. However, the tumour-bearing group (b) (n = 31) showed a significantly higher median score of 22. When group (a) was subidivided, it was shown that the patients who had an invasive growing melanoma with a bad prognosis (n = 11) showed a significantly higher median score of 25, while the patients who had a superficial melanoma with good prognosis were not different from the controls. After subdividing group (b), it was shown that patients with localized disease (n = 13) had a median score of 12, which not different from that of the controls. However, the patients with regional lymphnode involvement (n = 9) or distant metastases (n = 9) showed significantly higher median scores of 69 and 24 respectively. Six out of sixteen patients showed a significant drop in PMN inclusions after surgery. Complement scores gave similar patterns.


Circulating antigens and immune complexes in Schistosoma mansoni-infected rats. Characterization by radioimmunoprecipitation-PEG assay (RIPEGA). Circulating schistosome antigens (CSA) and circulating immune complexes (CLC) were investigated in rats infected with Schistosoma mansoni. The radioimmunoprecipitation-polyethylene glycol (PEG) assay (RIPEGA), with 125I-labelled anti-S. mansoni anti-serum, detected CSA during two distinct periods of the infection; the first between the 11th and the 14th week of infection and the second between the 11th and 14th week after infection. The CH50 deviation test revealed the presence of CIC in sera from infected rats, approximately at the two periods when CSA were detected. At 6 weeks of infection, the levels of CIC in infected rats were not different from those in control rats. However, a more sensitive method characterized IgG2a in C1q-binding C1C from infected rats. At weeks 5 and 6, IgE immune complexes were also detected in the serum from infected rats. In fact, the use of RIPEGA on the material eluted from infected rat serum after passage through an anti-IgE immunosorbent showed the presence of schistosome antigen at week 4, and at higher levels at week 6. Levels of 50% haemolytic complement in infected rat serum were lowered between the 2nd and the 4th week, the 5th and the 8th week and after the 12th week of infection. The possible role played by CIC in the protective mechanisms to a S. mansoni challenge infection in rats is discussed.


Interferon production and lymphocyte stimulation in human leucocyte cultures stimulated by Corynebacterium parvum. Killed C. parvum organisms stimulated a lymphoproliferative response in human peripheral leucocyte cultures of both adult and cord blood origin. They also induced high titres of interferon in cultures of adult leucocytes, but there was no correlation between the degree of lymphocyte stimulation and of interferon production. A considerable variability between donors was seen in both assays. The amount of interferon produced in C. parvum-stimulated cultures was considerably higher than that stimulated by the T-cell mitogens PHA and Con A and that induced by LPS. The anti-viral protein induced by C. parvum fulfilled the criteria of interferon and appeared to represent type II interferon.


Immunological recovery after measles.

Immunological recovery after measles. Twenty-two children with measles were studied at the stage of the rash and 6 weeks later, and results compared with matched controls. The total lymphocyte count and lymphocyte subpopulations with T- and B-cell markers and those with absence of both markers (null cells) were significantly below control levels in the acute phase. At 6 weeks the B-cell and null-cell counts were still significantly diminished. The function of T cells assessed by 14C uptake of phytohaemagglutinin-stimulated lymphocytes and the delayed skin hypersensitivity reaction to dinitrochlorobenzene was impaired during the acute stage, and this persisted for 6 weeks. Over the 6 weeks of study there was a small but significant rise in serum IgG, IgM and complement factors.


Effect of corticosteroids on committed lymphocytes. Human peripheral blood lymphocytes were cultured for 48 hr with concanavalin A. The amount of [3H]thymidine incorporated during the last 4 hr of culture, as well as the percentage of rosettes of activated lymphocytes generated, were assayed at the 48th hr. Adding 0.1 M alpha-methyl-D-mannoside (MAM) at progressively later times after the initiation of culture caused progressively less suppression because of the commitment phenomenon. This suppression was not exceeded by the addition of 10(-4) M preparations of corticosteroids and was statistically the same as that induced by a combination of both corticosteroids and MAM. The addition of PGE2 alone and in combination with methylprednisolone also failed to affect [3H]thymidine incorporation by committed lymphocytes.


Microvascular anastomosis and its application on the replantation of amputated digits and hands. Successful microvascular anastomosis depends upon the applications of magnifications, special instruments and fine suture materials, and the surgeon's skill in the technique. The key points of one millimeter vessel anastomosis are the wall-to-wall coaptation of the vessel ends, the fewer number of interrupted stitches with relatively loose knot. To gain good coaptation, an oblique insertion of a needle through the vessel wall must be used. In a thin-walled vein repair, the lumen should always be kept open with frequent irrigations. Between July 1965 and December 1976, 150 digits out of 168 in 111 cases and 11 hands in 11 patients were successfully replanted. All tissues must be repaired primarily. The repair of artery is performed first, recirculation is allowed with systemic heparinization, followed by vein anastomosis. The rehabilitation is commenced from the first day. To gain good function, several reconstructive surgeries may be necessary on the replanted digit or hand.


Common problems in clinical replantation and revascularization in the upper extremity. The restoration of viability to damaged or amputated tissues may be associated with a variety of unique situational and technical problems. The replantation surgeon must be aware of the many pitfalls which can occur in the care of these serious injuries in order to make appropriate decisions and execute the techniques of microsurgery effectively. The care of these patients begins with an accurate assessment of the injury and the potential functional restoration which can be achieved. It ends following a long rehabilitative and reconstructive effort to maximize ultimate function. All phases of this care are the responsibility of the replantation surgeon who must identify and attempt to solve these unique problems as they arise.


Great toe to hand free tissue transfer.

Great toe to hand free tissue transfer. Thumb reconstruction is a complex subject and the method selected for each patient deserves individual consideration. The method of free toe-to-hand transfer for thumb replacement should be chosen only when the surgeon is familiar with all alternative methods of thumb reconstruction and feels that this technique represents the most reasonable method available. For the surgeon a clear understanding of the anatomic similarities and differences between the normal thumb and great toe are mandatory. In well selected adults and children the failure rate for free toe-to-hand transfer should be very small. The advantages of a single staged thumb replacement from tissue of similar character and quality without local tissue sacrifice are tremendous. With improvement in techniques, experience and case selectiion, much free tissue transfers will actively compete with well established methods of thumb reconstruction. Surely the free toe-to-hand transfer for thumb replacement of today is a forerunner of thumb and hand transplantation of tomorrow.


Techniques of bone fixation and clinical experience in replanted extremities. Bone is shortened only enough to obtain skin closure or to remove excessive local comminution. Shortening is never done solely for the purpose of obtaining vessel apposition since vascular damage may extend beyond the zone of general soft tissue involvement. Fixation should be rapidly accomplished and be reasonably stable. Techniques are described. Following bony fixation, repair of flexor tendons and then nerves is carried out. Vessel repair using vein grafts to make up defects is then accomplished followed by loose skin closure.


Method of bone fixation in reattachment of amputations in the upper extremities. The object of secure bone fixation in the reattachment of amputated fingers is early motion. The use of specially designed screws and Kirschner wires is essential for this objective. This becomes even more important in the reattachment of fingers than the upper arm or forearm. If there should be non-union of the bone, an autologous bone graft should be applied as a secondary procedure.


Stabilization of bone in replantation surgery of the upper limb. The principles of sound osteosynthesis of the skeleton of the hand are the same as in internal fixation of other bones. Small implants and instruments are essential. In replantation surgery healing of microvascular anastomoses and nerve sutures as well as repaired tendons is possible when the skeleton is stabilized. Only the minimum metal should be implanted to avoid interference with joint and tendon function. A small implant can provide an adequate stability, when it is applied correctly. Replantation should be performed only by surgeons with extensive experience in the field.


Replantation and revascularization of amputated parts of extremities: a three-year report from the Viennese replantation team. A Replantation Team was instituted in Vienna 3 years ago. This team is the oldest in Europe. One hundred and eighty-one complete and incomplete amputated parts of 118 patients were replanted during this period. A survival rate of 86% and a useful functional result ("integrated parts") in 78% of the cases was obtained. Appropriate preparation of the amputated parts, the right timing, a 24 hour service and a clear indication with intensive postoperative physicotherapeutical treatment are the fundamental points for this result.


Transverse bayonet dislocation of the proximal interphalangeal joint. Complete dislocation of the proximal interphalangeal joint with complete rupture of both the collateral ligaments and volar plate was seen in 8 patients. We call this, "transverse bayonet dislocation of the proximal interphalangeal joint." When treated early, closed manipulation resulted in stable reduction. After a brief period of immobilization of 3 to 5 days with a dorsal aluminum splint, sustained active range of motion exercises were begun by strapping the injured finger to the adjacent finger obtaining good end results in all cases. An untreated dislocation of 5 weeks duration needed operative reduction. This was achieved with good result by release of all the retaining ligaments around the proximal interphalangeal joint including both the collateral ligaments, the volar plate, the transverse retinacular ligaments, and extensor tenolysis.


Traumatic arteriovenous fistula of the popliteal artery associated with a closed subtrochanteric fracture: report of a case. Major vascular injuries associated with closed fractures of the femur are rare. A 35-year-old man incurred a subtrochanteric fracture associated with an arterial injury distally. The femoral fracture type most likely to be associated with a major vascular injury is one near the junction of the middle and distal thirds of the bone. The mechanism involves tethering of the artery in the adductor hiatus. The location of the arterial injury is usually at the fracture site.


Epiphysiolysis as a method of limb lengthening. Epiphysiolysis followed by distraction was performed at the proximal tibial growth plates in 18 young rabbits. Union across the distracted plate occurred in all animals. In 12 rabbits skeletally immature at operation, premature fusion of the separated plate resulted in growth arrest of the operated limb. The contralateral control limb was longer at maturity by an average 1.10 cm. In 6 rabbits near skeletal maturity at epiphysiolysis, the operated limb was the longer at maturity by the amount distracted, an average of 0.62 cm. In all animals a permanent loss of joint motion resulted. Epiphyseal distraction in the very young rabbit does not appear to be practical due to consistent premature fusion of the distracted growth plate. It is possible to lengthen the limbs of rabbits near skeletal maturity with this procedure. An added advantage is that union between the epiphysis and the metaphysis always occurred, eliminated the problem of delayed ana non union found in diaphyseal lengthening. However, at this time, until the effects of distraction and compression on the adjacent joint can be minimized, epiphysiolysis as a method of limb lengthening is not recommended in children.


Ultrastructure of chondrogenetic interactions between bone matrix gelatin and mesenchymal cells. The ultrastructure of post fetal chondrogenesis was investigated in chondrogenetic implants and explants of bone matrix gelatin: (A) in direct contact with living cells; (B) separated from living cells by cellulose acetate membranes; (C) in serum or in a culture medium with no contact with living cells. Ruthenium red (RR) staining coarse granules free of interconnecting filaments aggregated in interstitial fluid and inside the surface of the bone matrix gelatin within 72 hours in systems with either direct or indirect contact with living connective tissue cells. No RR granules formed when control denatured or autolysed bone matrix gelatin were substituted for undenatured bone matrix gelatin. No RR granules formed in bone matrix gelatin incubated in serums or media in the absence of living cells in the system. These observations suggest the possibility that 4 days before overt transmembrane cartilage cell differentiation, covert (presumptive) chondroblasts synthesize and secrete precursor substance for aggregation of filament-free RR granules. The relationship between chondromorphogenesis and filament-free RR granules requires further investigation.


Digital replantation: clinical experiences. In a series of 130 digital replantations successful revascularization has been obtained in 74% of cases. Arterial thrombosis is the most common cause (65%) of all failures. A useful digit can be obtained following replantation and the surgery is particularly indicated for amputated thumbs and in hands suffering multiple injuries. Precautionary measures against bleeding are absolutely essential. Primary tendon and nerve repairs are advocated. Vascular occlusion may be corrected by revisional surgery and secondary surgery can improve tendon nerve or joint function.


Replantation of digits.

Replantation of digits. Replanted digital survivals range between 85% to over 90% at established microsurgery centers around the world. The time has come that all surgeons engaged in this activity must utilize the basic principles of reconstructive hand surgery in order to achieve the maximum functional return of the replanted parts. The vascular repair is only one step in the road toward functional restoration of the replanted part.


Nerve grafting.

Nerve grafting. By avoiding tension and securing anatomical neurorrhaphy, regeneration of nerve is obtainable. When the gap exceeds a certain limit, the only way to avoid tension is the use of grafts. Experience in animal experiments and clinical practice has demonstrated that regenerating axons can cross 2 optimal suture lines much more easily than one sub-standard one. For bridging a gap autografts are used, because in autografts the fascicular pattern is preserved and its Swann cells survive. With the interfascicular technique the dissection of the nerve stumps proceeds from normal to abnormal tissues and the epineurium is resected. The coaptation must be exact so that the grafts cover the whole cross sectional area of the fascicle. All this can be achieved by the use of one 10--0 or 11--0 nylon suture. The clinical results show that in the median nerve 82%, in the ulnar 80% and in the radial nerve 92% of good functional results can be obtained. Also in brachial plexus injuries the interfascicular nerve grafting procedure opened new ways. Therefore interfascicular nerve grafting, using autografts in cases of nerve repair, where a gap may occur, currently is the method of choice.


Nerve grafting with simultaneous microvascular reconstruction. A new method of nerve grafting is described that introduces the one stage distant transfer of a living nerve graft by microvascular techniques. The development of this operation is outlined and the first clinical application of this technique is presented together with the preliminary reports of 2 new cases. The blood supply of peripheral nerves is examined, and consequently a neurovascular bundle is defined as the best graft for free transfer. Donor sites are suggested for both normal and unusual circumstances, and a sequence of preoperative investigations and intraoperative precautionary steps is recommended, which can also be used as a basis for microvascular free transfer of other tissues. This technique of nerve grafting is designed primarily to ensure viability of the nerve graft. Because the procedure is exacting and time consuming, it is recommended only when conventional techniques carry high risk of graft necrosis, situations in which the nerve gap is large, the recipient bed is scarred, or the free transfer of a thick nerve is desired. There are disadvantages as well as advantages of the free vascularized nerve grafts. Important new developments in the field may depend upon advances in immunology.


Surgical treatment of traction injuries of the brachial plexus. A series of 508 patients with traction injuries of the brachial plexus (birth trauma excluded) has been investigated over a period of 11 years. Severe cases with root avulsions, ruptures of nervous pathways or severe disorganization of funiculi do not heal spontaneously or heal poorly. Whether these patients can benefit from modern microsurgical techniques (neurolyses, autologous nerve grafts and neurotizations with intercostal or other nerves) is presently under investigation. Operations were performed on 164 patients of whom 114 had root avulsions and 16 had 2 level injuries. Surgical treatment was planned according to the severity of the lesion. In about 10% no reconstruction was possible, or was of doubtful value. There is a striking difference in results of supraclavicular and distal, infraclavicular lesions. Only 55% positive of 58 patients of the first group were improved while 85% of 20 patients of the second group were benefited to some extent. None of the patients belonging to the first or second group recovered hand intrinsic function if pathways coming from C8 and T1 were injures. None recovered tactile gnosis. The effect on pain was sometimes ameliorative, but generally unpredictable.


Effect of procainamide on induced ventricular tachycardia. Ventricular extrastimulation was performed in 11 patients evaluated for chronic recurrent ventricular tachycardia, before and after a 1-gm procainamide infusion. Extrastimulation caused only nonsustained extra beats (less than 4) in 3 patients. Sustained tachycardia was induced in 7 patients in the basal state, of which 6 continued to have inducible tachycardia after procainamide was given (5.2 to 9.8 mg/L). The zone of coupling intervals that initiated tachycardia was unchanged or widened in these 6 patients because ventricular refractoriness was unchanged or because the tachycardia zone shifted to later diastole by an interval at least equivalent to the prolongation of ventricular refractoriness. Post-procainamide tachycardia cycle length was prolonged in all patients, by an average 51 msec. The one patient who responded to procainamide had a shortened ventricular refractory period, but the greatest slowing of tachycardia. Finally, sustained ventricular tachycardia could be induced in the eleventh patient only following procainamide administration, consistent with his clinical history. These results suggest that procainamide often may be ineffective in preventing sustained ventricular tachycardia, and that slowed conduction, rather than prolonged refractoriness, is the basis for the procainamide antiarrhythmic effect. Our data emphasize that antiarrhythmic drug effectiveness be evaluated in terms of effect on sustained arrhythmia rather than suppression of isolated ectopic beats.


Racial differences in drug metabolizing ability: a study with antipyrine in the Sudan. The kinetic disposition of antipyrine following oral administration of 1,200 mg has been investigated in 11 normal Sudanese subjects living in Sudan, 9 Sudanese subjects living in England for at least 2 yr, and 19 normal English subjects living in England. Sudanese subjects living in Sudan had significantly lower mean antipyrine clearance and higher volume of distribution than the English group (-28% and +30%, respectively). There was no significant difference for antipyrine clearance between English and Sudanese subjects living in England, but the volume of distribution of antipyrine was higher (16%) in the Sudanese subjects. The mean half-lives of the three groups differed significantly. We conclude that differences in disposition of antipyrine between native English and Sudanese populations was predominantly due to environmental factors.


Formation of a thiomethyl metabolite of phenacetin and acetaminophen in dogs and man. Conjugates of 3-methylthio-4-hydroxyactanilide were found in the urine of dogs and humans treated with phenacetin (4-ethoxyacetanilide) or acetaminophen (4-hydroxyacetanilide). About 1% to 3% of the administered dose was excreted as this thiomethyl metabolite after administration of phenacetin or acetaminophen to dogs. An average of 0.39% of the dose was excreted in the urine as 3-methylthio-4-hydroxyacetanilide conjugates after administration of phenacetin to several subjects, and an average of 0.66% of the dose was excreted as this metabolite in the urine after administration of acetaminophen to humans. The possibility that the thiomethyl metabolite is derived from a mercapturic acid conjugate or an N-hydroxy derivative of phenacetin or acetaminophen is discussed.


Effects of folic acid on phenytoin kinetics in healthy subjects. Phenytoin (DPH) disposition was studied in normal subjects before and after treatment with folic acid for 14 days. Our results suggest that folic acid lowers (DPH) serum levels without significantly modifying its bound fraction and increases the rate of DPH and meta-hydroxydiphenylhydantoin excretion in urine.


The interaction between indomethacin and probenecid. A clinical and pharmacokinetic study. The interaction between indomethacin and probenecid has been studied in 17 patients with rheumatoid arthritis with the use of a specific gas-liquid chromatographic method for the assay of indomethacin in plasma and urine. Probenecid in a dose of 0.5 gm twice daily improved the therapeutic response to indomethacin administered in a dose of 25 mg 3 times daily for a 3-wk period. There was an increase in the mean AUC of indomethacin in plasma from 2,553 +/- 213 hr ng/ml to 4,181 +/- 384 hr ng/ml when probenecid was given, but there was no change in the plasma half-life of indomethacin. There was a reduction in the mean plasma clearance of indomethacin from 174 +/- 21 ml/kg/hr to 107 +/- 14 ml/kg/hr when probenecid was added to the indomethacin therapy and a decrease in the apparent volume of distribution from 0,927 +/- 0.16 L/kg to 0.613 +/- 0.13 L/kg. There was no change in the amount of free indomethacin excreted in the urine during probenecid therapy but there was a reduction in the urinary excretion of free plus glucuronide conjugate of indomethacin from 8,967 +/- 867 microgram/day to 4,760 +/- 674 microgram/day, with a fall in the mean renal clearance of indomethacin glucuronide from 271 +/- 48 ml/min to 126 +/- 57.0 ml/min. The changes in the plasma indomethacin concentration profile during probenecid therapy are due to a decrease in the nonrenal clearance of indomethacin possibly because of reduced biliary clearance.


Time-course of interaction between carbamazepine and clonazepam in normal man. The applicability of a pharmacokinetic model for drug interactions by enzyme induction was tested by chronic dosing situation using carbamazepine (Tegretol) as the inducer and clonazepam (Clonopin) as the drug affected. Seven healthy subjects received one 1.0 mg clonazepam tablet once a day for 29 days and one 200 mg carbamazepine tablet once a day from days 8 to 29. Plasma levels of clonazepam were measured by electron-capture gas-liquid chromatography and those of carbamazepine and its epoxide metabolite by gas chromatographic-chemical ionization-mass spectrometry. Clonazepam plasma levels reached an initial steady-state by day 7 and declined to a lower steady-state over 5 to 15 days after additions of carbamazepine. The decrease in clonazepam levels ranged between 19% and 37%. Autoinduction of carbamazepine metabolism was also evident. Urinary excretion of D-glucaric acid increased 2- to 4-fold following carbamazepine administration (p less than 0.005). This increase provided additional evidence that the present interaction was due to enzyme induction. Experimental clonazepam levels were fitted to an induction pharmacokinetic model for multiple dosing with an exponentially increasing clearance. Induced half-lives of clonazepam (mean = 22.5 +/- 11.5 hr) were shorter (p less than 0.005) than control values (32.1 +/- 16.6 hr). Apparent enzyme(s) turnover half-lives ranged between 1 and 6 days.


Prediction of in vivo red cell/plasma Li+ ratios by in vitro methods. Two incubation procedures were used for the determination, in vitro, of the steady-state Li+ ratio between red cells and external media. The Li+ ratio in vitro determined prior to Li+ therapy correlates significantly with the subsequent ratio in vivo between red cells and plasma in patients treated with Li+. The Li+ ratio determined in vitro in patients during Li+ therapy was significantly higher than the value determined during the pretreatment, drug-free period that correlated significantly with Li+ ratios in vivo. The in vitro procedure used thus could be applied in the prediction of the in vivo Li+ ratio, and possibly of the response to Li+, in patients before treatment is begun. It also could be used for studies on abnormalities and on the genetics of Li+ transport in affective illness.


Adjustment of smokers to dilution of tobacco smoke by ventilated cigarette holders. This study was designed to examine the extent to which smokers would compensate for the dilution of smoke produced by ventilated cigarette holders. Peak plasma nicotine and carboxyhemoglobin levels were measured in 18 smokers when they had been smoking normally and when they had been using holders which dilute the smoke by about 20% (holder 1) and 60% (holder 2) for periods of 2 days and 7 days. Comparison of the observed blood levels with the "expected" levels estimated from the dilution factors of the holders showed that subjects partially compensated on holder 2 but showed little or no compensation on holder 1. There were no changes in the number of cigarettes smoked when using the holders so any compensation achieved must have been due to increasing the intake from each cigarette. There was wide individual variation in the amount of compensation with about 50% of subjects compensating fairly consistently on both holders. Degree of compensation was not significantly associated with usual cigarette consumption, plasma nicotine and carboxyhemoglobin levels when smoking without a holder, the nicotine yields of the subjects' cigarettes, or the experience of withdrawal symptoms and the degree of satisfaction when using the holders. It cannot be determined from this study whether the compensation observed was mediated by a need to regulate the intake of nicotine rather than some other factor.


Enhanced biotransformation of theophylline in marihuana and tobacco smokers. Single oral doses of theophylline were administered to 7 chronic marihuana smokers, to 7 chronic users of both marihuana and tobacco, and to 43 appropriate control subjects. Theophylline was cleared from the blood more rapidly in both marihuana and tobacco smokers with a mean increase in total clearance from 52 ml/kg/hr in nonsmokers to 74 ml/kg/hr in subjects who smoked either material alone. There was an additive increase in clearance to 93 ml/kg/hr in those who smoked both substances. Concern over enhanced metabolism of other drugs is probably warranted in tobacco and cannabis smokers.


Kinetics of acetaminophen absorption and gastric emptying in man. Eight healthy male volunteers ingested an aqueous solution containing acetaminophen (20 mg/kg) and a nonabsorbable isotopic marker. The concentrations of unconjugated acetaminophen in samples of blood plasma taken at frequent intervals were measured by gas-liquid chromatography. The data points followed a smooth curve in most cases and were fitted to the classical two-compartment pharmacokinetic model to obtain KA, the apparent first-order rate constant for absorption from the gastrointestinal tract. Gastric emptying was measured simultaneously from serial scintiscans of the subject's abdomen. The subjects were also studied after intramuscular injection of meperidine (150 mg) and pentazocine (60 mg) with and without naloxone (1.2 mg). The acetaminophen absorption curves and gastric emptying patterns were consistent with negligible absorption from the stomach. A new model is proposed in which the conventional single compartment used to represent the gastrointestinal tract is replaced by two compartments: one represents the stomach and the other the small intestine, from which absorption occurs rapidly. Pharmacokinetic analysis using this model showed good agreement in all cases, and provided an estimate of KA, the first-order rate constant for drug transfer from the intestinal lumen into the systemic circulation. The mean half-time for transfer was 6.8 +/- 0.9 min. As expected, KA was greater than KG (the first-order rate constant for gastric emptying), showing that gastric emptying was rate-limiting in the absorption of acetaminophen. The value of KA was greater than KA and the two were not related. The value of KA was not equal to KG in most studies because gastric emptying was not a single exponential process.


Clofibrate kinetics after single and multiple doses. The kinetics of chlorphenoxyisobutyric acid (CPIB) were studied in 5 healthy subjects after single 500-mg, 1,000-mg, and 2,000-mg doses of clofibrate, and in steady-state after 8 days' treatment with 1,000 mg twice daily. Maximum plasma concentrations of CPIB were observed 4 to 6 hr after dosing. A mean plasma half-life of 16.7 hr was recorded which was independent of dose and duration of treatment. Total plasma clearance (-Cl) calculated from area under the curve with the use of the total plasma concentration was 5.6 ml/min for the 500-and the 1,000-mg doses but increased to 6.8 ml/min for the 2,000-mg dose and was even higher (8.1 ml/min) in steady-state. This change in -Cl is a consequence of progressive reduction in the plasma protein binding of clofibrate at plasma concentrations above 50 microgram/ml, since -Cl rises in association with reduced protein binding at the high plasma concentrations measured after the 2,000-mg single dose and in steady-state. -Cl and apparent volume of distribution were identical for all doses tested when calculations were based on the nonprotein-bound CPIB concentrations only. Due to the inconsistant protein binding of CPIB, total steady-state concentrations could not be predicted from the single dose kinetic data.


Digoxin concentration in choroid plexus, brain, and myocardium in old age. Thirteen aged persons receiving digoxin until the time of death were examined by autopsy, and digoxin concentrations were determined in samples from various tissues (the choroid plexus, grey and white brain matter, left and right ventricular and left and atrial myocardium, diaphragm, and musculus psoas major).  These concentrations were related to the digoxin dose and duration of treatment. No significant difference was found between the concentration of digoxin in the choroid plexus and left ventricular myocardium, whereas there were significantly lower concentrations in the right ventricular myocardium and still lower concentrations in the other tissues analyzed. Independent of the digoxin dose, the digoxin concentrations in the choroid plexus tended to be lower in persons treated for a short time before death than in those treated for longer periods of time. Similar differences were not observed in the other tissues, suggesting a slower rate of digoxin uptake in the chroid plexus compared with the myocardium and other tissues. The implications of these findings for the effects of digoxin treatment on the production of cerebrospinal fluid are discussed.


Alterations in state in apneic pre-term infants receiving theophylline. The present study is a report on 9 premature infants treated with aminophylline for relief of apnea. With serum theophylline levels of 2 to 10 microgram/ml, all infants experienced significant decrease of apneic episodes in association with increased wakefulness and increased amounts of active (REM) sleep. These effects may occur independently, but it is possible that the alteration of sleep states may be partially responsible for the decrease in apneic episodes in these infants.


Functional and dysfunctional uterine bleeding. The patient who comes to the physician with abnormal bleeding represents an enormous responsibility. The various causative factors represent defects in numerous physiologic systems. The diagnosis of DUB still requires further investigation of the hormonal imbalance. Only when specific causes are known can the treatment be tailored to the particular patient. Recent scientific advances regarding possible cellular mechanisms for DUB make it mandatory that the primary physician be aware of available tests that may indicate the relative appropriateness of and prognosis for a particular therapy. The treatment is substitutional. If progesterone is missing, therefore,the treatment should replace it. Progesterone may be obtained endogenously by ovulation induction or exogenously by oral or parenteral progestogens.


Radiographic evaluation of renal masses. Radiologic evaluation of a renal mass involves two phases. Initial detection of the mass depends on high-quality excretory urography. Once detected, a number of diagnostic modalities are available to further evaluate the mass. The studies needed for any given mass can be kept limited, and, with careful use of the scheme presented, a diagnosis can be made with minimal invasiveness and expense.


Pharmacokinetic and pharmacodynamic studies of procainamide given intermittently intravenously in patients with severe ventricular arrhytmias. In 15 patients with coronary heart disease and ventricular arrhythmias 100 mg of procainamide was given intravenously every 5 min until arrhythmia was abolished, or the patient received 1000 mg of the drug, or side-effects appeared. Then patients were placed on oral maintenance therapy 3 or 4 g daily according to their weight. In 13 out of 15 patients arrhythmia was completely suppressed after intravenous injections of the drug. Plasma procainamide concentrations, including N-acetylprocainamide levels in some patients, were monitored and a therapeutic range of 6.3--10.3 microgram/ml for intravenous therapy was found. ECG intervals changes, slowing of heart rate and decrease in systolic and diastolic blood pressure were seen but no serious side-effects were observed. The significance of monitoring plasma drug concentrations, including levels of N-acetylprocainamide during prolonged maintenance therapy, have been discussed.


Plasma volume in men with low-, normal- and high-renin essential hypertension. Plasma volume [PV] and plasma renin activity [PRA] were measured in 51 men with untreated borderline and mild essential hypertension [I and II degree according to W.H.O. classification]. PV in low- and normal-renin hypertension was not significantly different from normal values. Groups of patients with low- and high-renin hypertension differed significatly from each other not only br PRA after stimulation, but also by PRA at rest, PV and age.


The triglyceride fatty acid pattern in arterial wall, adipose tissue and serum of amputated diabetic subjects. The triglyceride fatty acid pattern [TFAP] in arterial wall, adipose tissue and serum has been estimated in diabetic subjects by gas-liquid chromatography simultaneously. The samples were taken shortly before or during femoral amputation performed under halothane anaesthesia. In addition, in some probands the fatty acids of cholesterol esters of vascular walls have been obtained. The following differences in the TFAP of the tissues under study were discovered. In arterial wall compared to serum, lauric, myristic, myristoleic, palmitoleic, stearic, oleic and linolenic acid were increased; palmitic and linoleic acid were decreased, whereas eicosatrienoic, arachidonic and eicosapentaenoic acid were at the same level. In arterial wall compared to adipose tissue, myristic, palmitic and nervonic acid were decreased; eicosatrienoic, arachidonic and eicosapentaenoic acid were increased. Most differences concern the TFAP of adipose tissue compared to serum: lauric, myristic, myristoleic, palmitoleic, oleic, linolenic, lignoceric and nervonic acid were elevated in the former; palmitic, linoleic, eicosatrienoic, arachidonic and eicosapentaenoic acid were increased in the latter. In consideration of different content of fatty acids in the tissues studied the authors conclude that certain fatty acids have distinct metabolic positions such as depot fatty acids and precursors of prostaglandins.


Diagnostic significance of some accessory systems of electrocardiographic leads in early diagnosis of myocardial infarction on the basis of vector analysis. With a view to facilitating early diagnosis of myocardial infarction, the diagnostic significance was studied of 12 standard electrocardiographic leads and of accessory leads according to Nehb, Gurevich, and Slapak-Partilla. Attention was paid to the deflexion of the pathological vector from the positions of active electrodes in the above systems on the basis of vectorcardiographic findings. There were examined 300 patients with extensive myocardial infarction [84.7% of them already within 24 h after infarction] and 80 healthy control persons. Vectorcardiographic analysis showed that the Gurevich leads CKL, and the Slapak-Partilla leads S2(-4), and partially also S1, reflected lesions in posterobasal, and the Nehb leads, in lateral and posterolateral segments of left ventricular myocardium. Application of Gurevich leads and of Slapak-Partilla leads in combination with standard leads makes possible the recognition of lesions in both basal and septal segments of the posterior wall. Extensive necroses of this type should be termed extensive infractions of left ventricular posterior wall.


Reaction types of regional redistribution of blood. Changes are described in relative contents of blood in tissues and organs, usable for evaluation of regional redistribution of blood caused by various factors influencing the organism. Despite specific characters of such changes, several basic types were identified which may represent several phases of a general nonspecfic reation, whose character varies in dependence on the actual degree of stimulation or lesion. In the first phase the relative contents of blood increase in the brain, heart, lungs, and in the muscle and bone tissues of the head, neck , and thorax. The second phase is characterized by increased blood content in the liver. In the third phase blood is mobilized from the liver and redistributed into tissues exposed to functional loads, with marked anaemization of the liver. In the fourth phase the regional redistribution becomes pathological. Experiments were made in male albino rats exposed to various stresses [blood loss, confinement in a tight box, treadmill running, various types of general anaesthesia, and others].


Diffuse hair loss in women.

Diffuse hair loss in women. In summary, the presenting signs of diffuse hair loss was thinning of the scalp hair with associated receding of frontal and temporal hairlines. The majority of patients experienced telogen efflivium between the ages of twenty and sixty years. The hair loss could be classified according to the multiple presumptive etiologic factors; hereditary, hormonal, or systemic disorders, drugs, nutritional deficits, neoplasms, physical and chemical trauma, and psychological disorders. Of the 129 women evaluated, 30 percent had concomitant systemic disorders or precipitating causes. This report stresses the importance of a full hiar loss evaluation and an attempt to identify the etiologic factors or disease states that may precipitate or exacerbate an existing condition such as androgenic alopecia. It is hoped that the outlines for the initial history and examination presented in this report will help to direct the physician's evaluation of hair loss problems in women.


Treatment of "tinea pedis" with griseofulvin and topical antifungal cream. A protocol for determining the antifungal efficacy of systemic or topical drugs in tinea pedis is presented. In this study, (1) no patient had concomitant onychomycosis; (2) the clinical types were separated into (a) plantar scaling, (b) intertriginous, and (c) vesicular instep; (3) the soles were treated for three months (time related to the shedding of all stratum corneum); (4) the follow-up period for soles was three months (related to characteristics of the drug and its depot effect on the target area, the horny layer); (5) the final evaluation related to the percentage of patients "clinically and mycologically cured" at the end of the follow-up period. With this protocol, ultramicrosize griseofulvin (Gris-PEG) alone, topical clotrimazole (Lotrimin) alone, and a combination of the two were tested in seventy-three patients with tinea pedis. The results were as follows: for plantar scaling type of tinea pedis, the combination was not better than griseofulvin alone; for intertriginous tinea pedis, the combination was definitely better than griseofulvin alone; and topical 1 percent clotrimazole was much less effective than griseofulvin.


Timing of sessions in hair transplantation. The issue of timing between hair transplantation sessions is explored. An interval of three to four months between the second and third and third and fourth sessions of transplanting is recommended. This allows the physician to see the pattern of hair growth in all previously placed grafts and enables him to completely fill the spaces left between transplanted hairs rather than between graft edges. Unsightly gaps can be minimized and the need for "fillers" can be markedly reduced if this course is followed.


Hemodynamic effects of smoking cigarettes of high and low nicotine content. We studied the hemodynamic effects of smoking cigarettes with high and low contents of nicotine in young smokers free of coronary arterial disease. The smoking of one cigarette with a high content of nicotine produced a peak rise in cardiac output of 32 percent above baseline values, and the effect persisted for one hour. Smoking a cigarette with a low content of nicotine produced a peak rise of 13 percent above baseline values, with a duration of five minutes. The rise in cardiac output was almost entirely attributable to tachycardia, since stroke volume remained relatively constant. The smoking of a cigarette with high nicotine content also caused greater and more sustained elevation in systemic blood pressure than smoking a cigarette with low nicotine content. Thus, there was a responsiveness to the dose of nicotine in cigarettes smoked by young smokers free of coronary arterial disease.


Pulmonary function following the adult respiratory distress syndrome. Fifteen patients (range of ages, 18 to 35 years) who survived an acute episole of the adult respiratory distress syndrome caused by mechanical or thermal injuries, sepsis, and shock were studied during 1 to 30 months after recovery. The patients had had no previous pulmonary diseases, and only two had been smokers. All of the patients were asymptomatic, and their chest x-ray films were normal on follow-up examination. Tests of pulmonary function revealed mild abnormalities which consisted of reduction of pulmonary volumes, decreased carbon monoxide diffusing capacity, and a mild increase of alveolar-arterial oxygen pressure gradients in the early stage ofter recovery. Improvement was noted after a few months, but eight patients still had mild reduction of pulmonary volume after one to two years. No correlation could be established between the severity of the adult respiratory distress syndrome, therapy with mechanically assisted ventilation, the duration of exposure to supplemental oxygen, the fractional concentration of oxygen in the inspired gas, and the degree of residual functional defect.


Immune complexes in sarcoidosis: a correlation with activity and duration of disease. Samples of serum from patients with sarcoidosis were examined for the presence of immune complexes, using the Raji cell line. An indirect immunofluorescent technique was used to detect the binding of immune complexes to the complement receptors of Raji cells. Preliminary studies indicated that the method was sensitive and specific. We studied 44 patients with sarcoidosis who were separable into the following three distinct clinical groups: (1) acute disease (one year or less); (2) chronic active disease (five years or more); and (3) resolved disease (five years or more). In the 26 patients with acute disease, 12 had circulating immune complexes; immune complexes were present in two of the ten patients with chronic active disease. In contrast, immune complexes were absent in patients with resolved disease and normal control subjects. In patients with active disease, there was no apparent correlation between the presence of immune complexes and the stage of disease; however, immune complexes were present in five of the 11 patients with extrapulmonary disease, in seven of 12 patients with elevated concentrations of gamma-globulin, and in four of five of those patients with autoantibodies to lymphocytes.


Cardiac response during uninterrupted treadmill exercise and recovery: measurement by systolic time intervals. In 12 normal subjects, use of ear densitography permitted measurement of systolic time intervals (STI) during uninterrupted treadmill exercise to over 90 percent maximal heart rate on a modified Bruce protocol. Results for control (sitting leads to standing) leads to end-exercise at 18 minutes leads to 10 minutes' sitting recovery were--heart rate (HR): (77 leads to 861 leads to 171 leads to 98 beats per minute; preejection period (PEP): (106 leads to 111) leads to 49 leads to 110 msec; ejection time index (ETI) (351 leads to 330) leads to 380 leads to 366 msec; PEP/LVET (0.42 leads to 0.49) leads to 0.29 leads to 0.45. Heart rate increased steadily to 18 minutes. In contrast, the PEP/LVET decrease was almost complete by three minutes and both ETI and PEP responses were bimodal with respective plateaus between three and six minutes and three and nine minutes. All STI and HR curves showed rapid restitution during early recovery. The changes during treadmill exercise were numerically comparable to those during bicycle exercise at a common heart rate. The results indicate that it is technically feasible to measure systolic time intervals with precision during uninterrupted treadmill exercise; responses to treadmill exercise were in the direction expected and quantitatively comparable to bicycle exercise at comparable stress level. These obervations provide the technical and physiologic bases for applying this method in clinical treadmill exercise testing.


The diagnosis of sarcoidosis by conjunctival biopsy. A prospective study of 21 patients with presumed sarcoidosis was performed to determine the value of conjunctival biopsy in diagnosing the disease. Conjunctival lesions were seen in 15 patients on slit-lamp examination, with eight of these showing noncaseating granulomas on biopsy. The abnormalities were seen by the unaided eye in only two cases. All eight biopsies showing noncaseating granulomas occured in the 14 black patients. No clinical, biochemical, or radiographic characteristics identified those patients who would prove to have a biopsy showing such granulomas. This simple, frequently productive procedure may be helpful in the diagnosis of sarcoidosis.


His bundle recordings in atrioventricular nodal alternating Wenchebach periods ending in 5:1 atrioventricular block coexisting with paroxysmal atrioventricular nodal block. Atrioventricular nodal alternating Wenckebach periods ending in 5:1 atrioventricular block occurring during rapid atrial rhythms were explained by postulating the presence of block in three levels of the atrioventricular node. This pattern of conduction occurred in ten of 11 patients who either had received ouabain or verapamil (nine patients) or who had organic atrioventricular nodal disease (two patients). In contrast, this pattern of conduction occurred in only one of eight nonmedicated patients without organic atrioventricular nodal disease. The frequent association of this pattern with paroxysmal, tachycardia-dependent atrioventtricular nodal block suggested a similar, but not necessarily identical, mechanism. In conclusion, atrioventricular nodal alternating Wenckebach periods ending in 5:1 atrioventricular block, as well as paroxysmal atrioventricular nodal block, were only rarely the result of rapid atrial rates per se their occurrence indicating organic or pharmacologic effects on the atrioventricular node. Since both can be produced by carotid sinus pressure, further studies appear to be necessary to determine the role that vagal effects can have in their genesis.


Hemodynamic effects of long and multiple coronary arterial narrowings. The coronary hemodynamic influence of a series of coronary arterial narrowings was compared with single narrowings of the same total length and reduction in diameter in 12 dogs. Compared with single narrowings, two or three sequential narrowings had no significant effect on restng coronary blood flow. Small but significant mean pressure gradients were found for series of two and three 1-mm narrowings but not for single narrowings of the same total length. During reactive hyperemia, repayment of the debt in flow decreased significantly for single 2-mm and 3-mm narrowings, compared with 1-mm single narrowings. An additional decrease in repayment of the debt in flow occurred for two and three separate narrowings, compared with single narrowings. Our findings imply that when the reduction in the diameter of the coronary artery is fixed, an increase in the length or number of narrowings in series reduces the responses of coronary blood flow during reactive hyperemia.


Left ventricular function in chronic obstructive pulmonary disease. The presence or absence of left ventricular dysfunction in chronic obstructive pulmonary disease has been debated for decades. I have reviewed the following evidence pertaining to this topic: (1) left ventricular pathologic abnormalities; (2) the methods used to determine left ventricular performance; (3) specific abnormalities of left ventricular function as revealed by systolic time intervals, left ventricular end-diastolic pressure, ejection fraction, isovolumic indices, and left ventricular function curves; and (4) pertinent experimental data. The bulk of the evidence indicates that the clinical symtoms of left-sided failure are unreliable in those with obstructive disease of the airways and that the great majority of patients have normal left ventricular function, once other causes are excluded. A small group of patients have some abnormalities in left ventricular performance, but these have not been clinically significant. The ultimate importance of such abnormalities awaits future investigation.


Longterm favorable effect of oxygen administration on a patient with primary pulmonary hypertension. A 17-year-old girl with primary pulmonary hypertension was treated with longterm administration of oxygen. Oxygen was delivered only at night for eight hours daily. Her clinical status has been improved for more than 17 months. Cardiac catheterization revealed almost 50 percent reduction of pulmonary vascular resistance. This is the first known report of successful treatment of primary pulmonary hypertension with oxygen administration.


Massive intrabronchial aspiration of contents of pulmonary abscess after fiberoptic bronchoscopy. A patient with a putrid pulmonary abscess that did not resolve developed massive aspiration of the contents of the cavity following a fiberoptic bronchoscopic procedure. Precautions for before and after a bronchoscopic procedure are suggested to prevent this catastrophic complication in patients with pulmonary abscesses.


Progressive development of a left ventricular thrombus. In a patient with ischemic heart disease and terminal left ventricular failure, echocardiographic techniques (single-crystal M-mode echocardiograms and bidimensional, linear, dynamically focussed multiscan recordings) allowed the detection and follow-up of a left ventricular thrombus, later documented at autopsy.


Noncardiogenic pulmonary edema following blood transfusion. Noncardiogenic pulmonary edema and acute respiratory failure were found to develop after blood transfusion. Pulmonary antiographic studies and hemodynamic measurements were performed in the presence of pulmonary edema. Normal wedge pressure was observed at the time of angiographic studies, and contrast material appeared to extravasate across the alveolocapillary membrane into the alveoli. The mechanisms of acute injury to the alveolocapillary membranes and of pulmonary edema secondary to reactions to transfusion are discussed.