Serum prostate-specific antigen measured in children from birth to age 18 years

We measured prostate-specific antigen (PSA) in serum from 94 cord- blood samples, from 44 newborns, and from 330 children up to age 18 years, using a highly sensitive "third generation" PSA assay on the IMMULITE (Diagnostic Products Corp.) analyzer. The serum was that remaining after cross-matching for blood transfusion. Most children were hospitalized for special care or surgery. We found detectable concentrations of PSA (> or = 0.003 micrograms/L) in many cord sera and in sera from both male and female neonates. PSA was more frequently detectable in cord and newborn sera from males than from females, but there was considerable overlap in values between the sexes, negating any possible usefulness of PSA for assigning male gender to newborns with ambiguous genitalia. PSA decreased to undetectable concentrations in most prepubertal males and females but became detectable around the age of puberty in males. We speculate that the presence of detectable PSA in cord and newborn sera results from androgenic stimulation of prostatic tissue in males or from stimulation of breast or other tissue by prolactin or progesterone in females.

Clinico-pathological predictors of recurrence for acinic cell carcinoma

The biological behaviour of acinic cell carcinomas, even if well differentiated, is unpredictable. We studied 45 patients with acinic cell carcinoma followed-up from 10 to 379 months (5 year recurrence-free and survival rate of 69% and 81% respectively), and compared clinico-pathological parameters with outcome. The presence of a predominately solid architecture was strongly associated with a poor outcome (P < 0.01) and this was the only independent prognostic variable when log rank testing was performed. Tumour size (> 2.75 cm) was a significant predictor of recurrent deep parotid lobe involvement, the presence of cervical nodal disease and lymphocytic infiltration, although not significant, factors showed a tendency towards recurrence. For acinic cell carcinoma, the predominant solid architecture would appear to be a strong predictor of recurrence.

Decision making in the treatment of school-age children who stutter

The purpose of this article is to provide clinicians information on some of the key issues in making decisions about the treatment process for children who stutter. Ten decisions that should be considered prior to, during, and at the time of dismissal are discussed. These decisions relate to a number of issues regarding treatment such as: increasing clinicians' confidence in treating stuttering in children, setting long- and short-term goals, selecting an approach to treatment, documenting progress, involving parents and teachers in the treatment process, and determining when the child is ready to be dismissed from treatment. Additionally, questions clinicians should ask themselves are presented with each of the ten decisions. The intent of this article is to show how an analysis of clinical information systematically collected over a period of time will help a clinician make accurate decisions about the treatment of children who stutter.

Interference in triiodothyronine (T3) analysis on the Immuno 1 Analyzer

OBJECTIVE

To evaluate the interference in Triiodothyronine (T3) analysis on the Immuno 1 Analyzer.

METHODS

We analyzed 686 samples for T3 using the Miles Technicon Immuno 1 Analyzer. We compared the results of 318 samples with those given by radioimmunoassay (RIA) and the remaining 368 results with those given by the Ciba-Corning ACS 180 analyzer.

RESULTS

On the Immuno 1 correlated with those by RIA or chemiluminescence immunoassay. However, results on eight patients by the Immuno 1 method were anomalously elevated. We attempted to find and eliminate the cause of the interference on the Immuno 1. Although the method uses an alkaline phosphatase labelled T3 analog and fluoresceinated monoclonal antibody, serum binding of fluorescein or alkaline phosphatase did not appear to be the major causes of the interference. Ethanol extraction of samples followed by reconstitution in zero calibrator was the only reliable way to eliminate the interference.

CONCLUSION

The Immuno 1 assay was more prone to interference than other methods. Until it is reformulated, we recommend that users assay ethanol extracts of samples with unexpectedly high T3.

Psychosocial problems in primary care. Pilot study of a new taxonomy

BACKGROUND

In this study, the Massachusetts Academy of Family Practice Research Network (MAFP ReNet) was used to test a new taxonomy of psychosocial problems presenting to family physicians and to examine physician variability in determining when a psychosocial problem plays a role in a patient's visit.

METHODS

Thirty physicians completed a form listing the taxonomy of psychosocial issues for 19 standard case vignettes. These physicians then completed the same form for every patient seen in their practices over a 2-week period.

RESULTS

The proposed taxonomy was well received by practicing physicians as appropriate for how they think about their patients and practices. The case vignettes demonstrated a large variability in physician identification of psychosocial problems. The 30 physicians who participated in all phases of the study completed evaluations of 2876 patient visits, identifying 43% of these as involving one or more psychosocial problems. The frequency of psychosocial problem identification among the physicians ranged from 23% to 81%, with a standard deviation of 15%.

CONCLUSIONS

The proposed new taxonomy may be helpful in both future research and teaching. The high degree of variation in physician responses both to the same clinical vignettes and to patients in their practices suggests that physicians vary widely in their identification of psychosocial issues.

The test-retest reliability of the Mini-Mental State Examination in chronic schizophrenic patients

The test-retest reliability of the Mini-Mental State Examination (MMSE) was explored in a sample of 22 inpatients suffering from chronic schizophrenia by DSM-III-R criteria. Patients were tested 4 times during a period of 4-6 weeks. The total score for serial sevens showed consistently significant reliability at about 0.7, and the total score for spelling displayed a lower reliability at about 0.4, which was of borderline significance. In this short period of time, 36% and 27% of the patients shifted between being demented and nondemented when the serial sevens and spelling, respectively, were used to calculate total scores. The MMSE should not be used to categorize schizophrenics as demented or nondemented in biological studies using relatively stable variables.

Feasibility of dose-intensive continuous 5-fluorouracil, doxorubicin, and cyclophosphamide as adjuvant therapy for breast cancer

BACKGROUND

Several studies support the belief that the efficacy of adjuvant chemotherapy in breast cancer is related to the dose intensity of the chemotherapy used (expressed in milligrams per square meter per week). Retrospective analyses indicate that the actual delivered dose intensity may correlate more strongly with efficacy than the intended dose delivery.

METHODS

A doxorubicin-based adjuvant regimen was studied for breast cancer. It was modeled on the Southwest Oncology Group's regimen of cyclophosphamide, methotrexate, and 5-fluorouracil in that daily oral cyclophosphamide and weekly intravenous 5-fluorouracil were used, but weekly doxorubicin was substituted for methotrexate and administered in both the adjuvant and neoadjuvant setting to 29 patients.

RESULTS

The actual dose delivery was 1.21-1.24-fold that calculated for the delivered dose in the two other adjuvant regimens using the same three drugs (5-fluorouracil, doxorubicin, and cyclophosphamide) for which this could be determined. This regimen was tolerated well. Toxicity was minimal and consisted largely of expected neutropenia.

CONCLUSIONS

Whether improved dose intensity can be increased further with the use of growth factors or actually confers improved outcomes awaits the results of larger future trials.

Attitude of healthcare personnel regarding influenza immunization

OBJECTIVES

To survey the attitudes of healthcare personnel regarding influenza immunization.

DESIGN

A questionnaire was given to all hospital employees.

SETTING

A 650-bed community teaching hospital.

INTERVENTION

Employees were offered an in-service regarding influenza immunization in October 1991. Influenza immunization was given free of charge by Employee Health Services from October to December 1991. One thousand fifty-six employees (30.2%) received influenza vaccines. Survey forms were distributed with paychecks to all employees during the second half of January 1992. Completed survey forms were returned during the next 2 weeks.

RESULTS

One thousand two hundred three of the 3501 (34.3%) questionnaires were returned. Some of the survey forms were not completely filled out. A total of 28.1% of male employees (202/717) and 35.4% of female employees (987/2783) (p < .01) responded. Mean years employed were 11.35 +/- 7.57 for respondents and 9.30 +/- 7.39 for all employees (p < .001). Four hundred sixty-one respondents (38.4%) received the influenza vaccine and 734 (61.4%) did not. Among the respondents, employees who were older or working full time were more likely to receive the vaccine. Proportionally, more respondents who received the vaccine attended the in-service, although only 8.7% of those immunized attributed their receiving influenza vaccine to the in-service. More physician respondents were vaccinated. The respondents who received influenza vaccine were more likely to have received the vaccine during the past 2 years (p < .001). The major reasons given for not receiving the vaccine were "bad side effects" and "do not like shots." The major side effect of influenza immunization was a "sore arm." Multivariate analysis suggested that the in-service was not associated with obtaining the vaccine.

CONCLUSIONS

The in-service regarding influenza immunization seemed to have a negligible influence. Most employees who received the vaccine had previous influenza immunization. There were no major side effects of influenza immunization. "Bad side effects" and "do not like shots" were major reasons given for not receiving influenza vaccine.

Identification of the steroids in neonatal plasma that interfere with 17 alpha-hydroxyprogesterone radioimmunoassays

Neonatal plasma contains interferents that increase the apparent 17 alpha-hydroxyprogesterone (17-OHP) content measured by direct (no-extraction) radioimmunoassay. We fractionated extracts from neonatal plasma pools by liquid chromatography with a Sephadex LH-20 column and measured 17-OHP immunoreactivity by a direct test kit. We found immunoreactivity in the free steroid and glucuronide fraction and also in the monosulfate fraction. We analyzed these two fractions by reversed-phase high-performance liquid chromatography (HPLC) and HPLC-mass spectrometry. We collected fractions and assayed for 17-OHP immunoreactivity. The HPLC fractions containing the interfering steroid monosulfates were analyzed by ion-spray mass spectrometry and, after solvolysis, by gas chromatography-mass spectrometry. Several monosulfates were identified, including those of 17 alpha-hydroxy-pregnenolone, 16 alpha-hydroxypregnenolone, pregnenolone, and several pregnenetriols. 17 alpha-Hydroxypregnenolone sulfate was the most significant interferent. Other commercially available 17-OHP assays showed similar interference when used without an extraction step. Kit manufacturers should select antibodies and protocols to minimize cross-reaction with sulfates, especially 17 alpha-hydroxypregnenolone sulfate.

Vaginal PO2 in healthy women and in women infected with Trichomonas vaginalis: potential implications for metronidazole therapy

We measured the PO2, pH, and temperature in the vaginal canals of nine patients with symptomatic Trichomonas vaginitis and those of 10 healthy women. The patients included eight women with primary infections caused by metronidazole-susceptible strains and one refractory case that resulted from infection with a metronidazole-resistant Trichomonas vaginalis. The median vaginal PO2, pH, and temperature in the patient group were 1 mm Hg, 6, and 37.3 degrees C respectively; these medians were 1 mm Hg, less than or equal to 4.5, and 37.2 degrees C in the healthy group. These data show that vaginal environment is anaerobic or microaerophilic (it has reduced oxygen tension). Because the activity of metronidazole is reduced under aerobiosis, the vaginal environment should enhance the biologic activity of the drug.

Captopril test in children with reflux nephropathy

We studied the plasma renin activity (PRA) and blood pressure (BP) responses to a single oral dose of captopril in children with renal scarring due to vesicoureteral reflux. The test was performed on 19 children, of whom 13 were normotensive and 6 hypertensive. Basal PRA was within the normal range for age for all except 1 patient. Mean basal PRA values for normotensive and hypertensive patients were not significantly different. At 90 min post captopril, the mean PRA increase was 3.61 ng/l per second (SD = 7.07) in the normotensive group but only 0.77 ng/l per second (SD = 0.83) in the hypertensive group. In 11 patients the average systolic BP 60-90 min post captopril was 0.9%-12.4% lower than the basal value. Diastolic BP decreased after captopril administration in 10 patients and increased in 9. The changes in mean arterial pressure and PRA between 0 and 90 min post captopril were inversely correlated (r = 0.605, P less than 0.01). Because of the PRA responsiveness in the normotensive patients with renal scarring, we suggest that there was activation of the renin-angiotensin axis in this group. However, it is not apparent whether such patients are more at risk of developing hypertension at a later time.

Serum 17 alpha-hydroxyprogesterone in infants and children as measured by a direct radioimmunoassay kit

A direct 17 alpha-hydroxyprogesterone (17-OHP) radioimmunoassay kit was used for the assay of samples from 219 infants and children. The kit was used according to the manufacturer's protocol on unextracted serum or plasma and also on reconstituted material extracted from the serum with propanol-heptane. The extraction protocol recovers approximately 88% of 17-OHP. Patients were grouped as infants 3-90 days (96 subjects) or older children, adolescents and young adults 91 days-20 years (123 subjects). 17-OHP results by the direct and extraction protocols correlated but the slopes of the regression lines (0.43 and 0.63) differed in the two groups, indicating that only about 49% of the immunoreactive material measured by the kit in the infants was 17-OHP whereas the corresponding percentage was 72% in the older children. Despite this nonspecificity, the present antibody is much more specific for 17-OHP in the presence of neonatal plasma steroids than that used previously. Reference values were obtained for the two groups using the method with and without an extraction step. 17-OHP values on four untreated patients with CAH were clearly elevated at the time of diagnosis. It is recommended that when the kit is used with neonatal and infant samples, an extraction step should be incorporated to enhance specificity.

Primary hyperparathyroidism and coexisting nephrogenic diabetes insipidus: rapid postoperative correction

Shortly after diagnosis of primary hyperparathyroidism, a patient had serum hyperosmolality, polyuria, isosthenuria, profound potassium depletion, and elevated plasma antidiuretic hormone levels, all consistent with nephrogenic diabetes insipidus. After parathyroidectomy, serum calcium and serum osmolality levels fell concurrently. Profound potassium deficits did not recur. We propose that (1) hypercalcemia produced a concentrating defect and polyuria; (2) renal tubular acidosis and polyuria combined to produce severe potassium depletion; (3) hypokalemia potentiated the nephrogenic diabetes insipidus caused by hypercalcemia; and (4) postoperative disappearance of the diabetes insipidus confirmed its reversible, purely metabolic causes.

Expression of Her-2/neu oncogene protein product and epidermal growth factor receptors in surgical specimens of human breast cancers

Her-2/neu protein product was immunocytochemically analyzed in 139 breast cancers. Epidermal growth factor receptors were similarly analyzed in 74 breast cancers from the same patient pool. These results were also separated on the basis of estrogen receptor proteins and of combined aneuploidy with elevated S-phase from flow cytometry. Invasive breast cancer yielded a positive label for Her-2/neu protein (26%) and for epidermal growth factor receptor (25%), with no significant difference. Correlations with estrogen receptor labeling yielded differences significant inversely for both Her-2/neu protein (p less than 0.02) and epidermal growth factor receptor (p less than 0.01). Positive Her-2/neu protein labels correlated with a positive combination of aneuploidy and elevated S-phase (37%) and a negative combination of aneuploidy and elevated S-phase (21%), with a statistically nonsignificant difference. Positive epidermal growth factor receptor cases with aneuploidy and an elevated S-phase (75%) and without aneuploidy and elevated S-phase (42%) did differ with significance at p less than 0.05. There were eight cases positive for both Her-2/neu protein and epidermal growth factor receptor, four of six cases with negative estrogen receptor, four of six cases with negative estrogen receptor, six of six cases aneuploid, and five of six cases with an elevated S-phase. All eight cases had threatening disease--either stage III or stage IV, with one case of extensive ductal carcinoma in situ (comedo). Correlation of negative Her-2/neu protein with negative epidermal growth factor receptor was significant (p less than 0.05) in 74 cases. However, positive Her-2/neu protein did not correlate with positive epidermal growth factor receptor; there was a trend toward inverse correlation. We conclude that epidermal growth factor receptor labeling results show similarities to Her-2/neu protein results, but epidermal growth factor receptor tended to correlate with unfavorable ploidy and S-phase. Epidermal growth factor receptor labeling might be useful in breast cancers with macrocysts reported to show high epidermal growth factor activity.

Sensitive time-resolved fluorescence immunoassay of somatotropin in serum

We describe a new "sandwich"-type non-isotopic immunoassay for human somatotropin (GH, growth hormone) in serum. In the assay, GH is captured by a monoclonal antibody immobilized in a white microtiter well and simultaneously reacted with a second biotinylated monoclonal antibody. The degree of binding of biotinylated antibody, which increases with increasing amount of GH in the sample, is quantified by adding streptavidin labeled with the europium chelate of 4.7 - bis(chlorosulfophenyl) - 1.10 - phenanthroline - 2.9 - dicarboxylic acid. The fluorescent complex on the solid phase is then measured by excitation at 337.1 nm (nitrogen laser) and monitoring the emission at 615 nm in a gated fluorometer/analyzer. The proposed procedure has short incubation times (less than 4 h protocol), uses only 25 microL of serum per microtiter well, and gives precise and accurate results. The method was clinically evaluated with samples obtained from pediatric patients undergoing investigation for growth abnormalities and from a patient with acromegaly.

Sensitive time-resolved fluorescence immunoassay of somatotropin in serum

We describe a new "sandwich"-type non-isotopic immunoassay for human somatotropin (GH, growth hormone) in serum. In the assay, GH is captured by a monoclonal antibody immobilized in a white microtiter well and simultaneously reacted with a second biotinylated monoclonal antibody. The degree of binding of biotinylated antibody, which increases with increasing amount of GH in the sample, is quantified by adding streptavidin labeled with the europium chelate of 4.7 - bis(chlorosulfophenyl) - 1.10 - phenanthroline - 2.9 - dicarboxylic acid. The fluorescent complex on the solid phase is then measured by excitation at 337.1 nm (nitrogen laser) and monitoring the emission at 615 nm in a gated fluorometer/analyzer. The proposed procedure has short incubation times (less than 4 h protocol), uses only 25 microL of serum per microtiter well, and gives precise and accurate results. The method was clinically evaluated with samples obtained from pediatric patients undergoing investigation for growth abnormalities and from a patient with acromegaly.

A survey of observation units in the United States

Observation units have been proposed as a tool in lowering over-all health care costs and increasing the quality of care in outpatient facilities. Emergency department (ED) use of these units has been evaluated at single facilities but never at a national level. A survey of 250 facilities across the United States was performed to gather information about the observation unit phenomenon. Of the 250 hospitals in the survey group, 27% had operational observation or holding units and another 16% planned units within 1 year. A statistically significant increase in the use of these units was noted in nonteaching facilities when compared with their teaching counterparts. A trend toward higher use of observation units in suburban/urban settings was noted when compared with rural locations, although the difference was not statistically significant. Of the units in existence, 93% were located within the ED, staffed by emergency physicians, and administrated by the ED director. Most are staffed by ED nurses and ancillary help. No hospital had both an ED unit and a non-ED unit, and many units functioned as both holding and observation areas. The units are perceived to be beneficial in patient care and in lowering health care casts, although objective documentation to validate these beliefs is lacking. Further prospective research is needed to evaluate these units scientifically before broad recommendations can be made.

Monoclonal antibodies for detection of occult carcinoma cells in bone marrow of breast cancer patients

Metastases develop in 30% to 40% of patients with operable breast cancer. Investigators have reported on the detection of occult micrometastases in bone marrow using an antibody to epithelial membrane antigen (EMA) and have since reported prognostic significance for these antibody-detected cells. In this study, two anti-cytokeratin monoclonal antibodies (35 beta H11 and 34 beta E12) were used to examine bone marrow specimens from patients with breast cancer. The technique was first studied in a test system in which human or monkey bone marrow was seeded with MCF-7 cells, and was determined to be sensitive enough to detect fewer than one cancer cell in 10(4) hematopoietic cells. An immunoglucose oxidase method was used for patient specimen antibody localization and was found to be free of false-positive staining. Marrow specimens from 25 patients with breast cancer of various stages were examined. No correlation with disease stage was observed. We conclude that the technique is feasible, but prognostic import remains to be determined.

Nonspecificity of a direct 17 alpha-hydroxyprogesterone radioimmunoassay kit when used with samples from neonates

We analyzed 240 samples for 17 alpha-hydroxyprogesterone (17-OHP) with the direct-assay kit ("Coat-A-Count" method for serum samples) from Diagnostic Products Corp. (DPC). The specimens were from 50 patients with known or suspected congenital adrenal hyperplasia (CAH); 74 mostly hospitalized neonates and infants, ages three days to three months; and 116 other patients, ages six months to 23 years. Samples from the CAH group were also analyzed with our in-house assay. For 39 of the neonatal samples, the analysis with the DPC assay was repeated with re-solubilized material that had been extracted from the serum with organic solvents. Values for "17-OHP" measured with the DPC direct assay were high, not only in CAH patients, but also in many of the unaffected neonates and infants. The extraction properties of the cross-reacting immunoreactive material into various organic solvent systems were different from those of 17-OHP, and were more like those of steroid sulfates. Because of this significant cross-reactivity, we recommend that the DPC kit not be used for sera from children younger than six months of age, unless the method is modified to include an extraction step.

Nonspecificity of a direct 17 alpha-hydroxyprogesterone radioimmunoassay kit when used with samples from neonates

We analyzed 240 samples for 17 alpha-hydroxyprogesterone (17-OHP) with the direct-assay kit ("Coat-A-Count" method for serum samples) from Diagnostic Products Corp. (DPC). The specimens were from 50 patients with known or suspected congenital adrenal hyperplasia (CAH); 74 mostly hospitalized neonates and infants, ages three days to three months; and 116 other patients, ages six months to 23 years. Samples from the CAH group were also analyzed with our in-house assay. For 39 of the neonatal samples, the analysis with the DPC assay was repeated with re-solubilized material that had been extracted from the serum with organic solvents. Values for "17-OHP" measured with the DPC direct assay were high, not only in CAH patients, but also in many of the unaffected neonates and infants. The extraction properties of the cross-reacting immunoreactive material into various organic solvent systems were different from those of 17-OHP, and were more like those of steroid sulfates. Because of this significant cross-reactivity, we recommend that the DPC kit not be used for sera from children younger than six months of age, unless the method is modified to include an extraction step.

Amiodarone therapy effects on childhood thyroid function

Thyroid function was systematically evaluated in 15 consecutive children (mean age 13.7 years, range 0.5 to 19.5 years) before and serially during treatment with amiodarone (Cordarone), a potent antiarrhythmic agent. Amiodarone is known to affect thyroid homeostasis by competitive inhibition of 5'-monodeiodinase, which converts L-thyroxine (T4) to triiodothyronine (T3) and reverse T3 (rT3) to 3,3'-diodothyronine (T2), and also by the direct effects of its high iodine content (37% by weight). Clinical and/or biochemical evidence of hypothyroidism occurred in three patients, two of whom required treatment with L-thyroxine. An additional patient had persistent hyperthyroxinemia but no clinical evidence of hyperthyroidism. Results from the patients who remained euthyroid showed characteristic alterations in serum thyroid function tests. These included significant increases in serum T4, rT3, basal thyroid-stimulating hormone and thyroid-stimulating hormone response to thyrotropin-releasing hormone testing. These changes were considered to be compensatory adjustments by the pituitary-thyroid axis to competitive inhibition of 5'-monodeiodinase by the amiodarone. Routine screening of thyroid function is needed to allow early detection of hypothyroidism when these compensations fail to occur.

Characterization of phosphohydrolase activity in bovine spleen extracts: identification of a bis(p-nitrophenyl)phosphate-hydrolyzing activity (phosphodiesterase IV) which also acts on adenosine triphosphate

Several bovine spleen enzymes with acid pH optima, some of which hydrolyze bis(p-nitrophenyl)phosphate and therefore fit the definition of "phosphodiesterase IV," were partially separated by isoelectric focusing and ion-exchange techniques. The activities were characterized by zymogram analysis with the aid of p-nitrophenyl and 4-methylumbelliferyl phosphate and phosphonate substrates. A number of these enzymes meet the criteria for phosphodiesterase I or other phosphodiesterases. However, the predominant phosphodiesterase I hydrolyzes the bis(p-nitrophenyl)-and 4-methylumbelliferyl phosphates, p-nitrophenyl and 4-methylumbelliferyl phenylphosphonate, and ATP at the beta-gamma bond, but not p-nitrophenyl or 4-methylumbelliferyl 5'-thymidylate (the usual PDE I substrates). These properties, as well as the pH optimum, distinguish the activity from the previously described, alkaline pH optimum PDE I. A second phosphodiesterase hydrolyzes only the phenylphosphonates. Several other activities, less well described, are apparent on zymograms. None of the phosphodiesterases IV was also a phosphodiesterase II (no hydrolysis of 4-methylumbelliferyl 3'-thymidylate).

Myocardial ischaemia in asphyxia neonatorum. Electrocardiographic, enzymatic and histological correlations

Serial electrocardiograms and creatine kinase (CK) isoenzyme activities were studied prospectively in 20 asphyxiated term newborn infants and 43 normal neonates. By adapting a previously described grading system for ischaemic changes, a degree of electrocardiographic ischaemia was defined which occurred almost solely in asphyxiated infants. Infants with this degree of abnormality had significantly higher mean CK-MB and MM activities than other asphyxiated infants at 0, 8 and 28 hours. Histological changes of peripartum myocardial necrosis were seen in 4 of the 5 infants on whom an autopsy was performed, and either electrocardiogram or CK-MB was abnormal in all four. It is concluded that myocardial injury in the newborn period is often associated with CK-MB release, but in view of the lack of cardiac-specificity of CK-MB in newborn infants, caution is urged in the interpretation of elevated isoenzyme activity in the neonate.

Serum dehydroepiandrosterone sulfate in a normal pediatric population

Dehydroepiandrosterone sulfate (DHAS) was measured in serum from 274 children and adolescents aged 1 month to 18.7 years, and in 38 healthy adults. In the pediatric group, which comprised 131 males and 143 females, serum DHAS was markedly age-dependent. Values declined between 1 and 5 months after birth, but were generally less than 4 mumol/L. Between 6 months and 7 years DHAS was less than 0.5 mumol/L in boys and less than 1.0 mumol/L in girls. Above 8 years DHAS progressively increased in both sexes to less than 13 mumol/L in mid-late teenage males and less than 12 mumol/L in females of the same age, similar to the values observed in the adults. In children and adolescents over 10 years, there was considerable overlap in DHAS values between groups of children classified by pubertal stage, resulting from the dissociation between adrenal and gonadal development during normal puberty.

An automated "high-pressure" liquid-chromatographic assay for hemoglobin A1c

An automated "high-pressure" liquid-chromatographic assay for hemoglobin A1c is described. We use a 45-min incubation in acetate buffer (pH 5.5) to eliminate labile glycated hemoglobins. In this automated system conventional modules are used but it incorporates a solvent-switching valve to select either of two buffers, which differ in pH and NaCl concentration. The chromatographic column contains "polyCAT" (a weak cation-exchanger, polyaspartic acid linked to silica). Run time is 14 min per sample. The method is precise and results correlate well with those by other ion-exchange procedures.

An automated "high-pressure" liquid-chromatographic assay for hemoglobin A1c

An automated "high-pressure" liquid-chromatographic assay for hemoglobin A1c is described. We use a 45-min incubation in acetate buffer (pH 5.5) to eliminate labile glycated hemoglobins. In this automated system conventional modules are used but it incorporates a solvent-switching valve to select either of two buffers, which differ in pH and NaCl concentration. The chromatographic column contains "polyCAT" (a weak cation-exchanger, polyaspartic acid linked to silica). Run time is 14 min per sample. The method is precise and results correlate well with those by other ion-exchange procedures.

Assessment of neurologic outcome in asphyxiated term infants by use of serial CK-BB isoenzyme measurement

Brain-type isoenzyme of creatine kinase was measured serially in 45 healthy and 22 severely asphyxiated term infants. The enzyme was measured in cord blood and in venous, capillary, or arterial blood at six to eight hours, 24 to 30 hours, and 72 to 80 hours after birth. In the healthy infants a brief rise of CK-BB occurred at six to eight hours; CK-BB activities were greater than 2.5 log-transformed standard deviations above the mean of the control values in ten of the asphyxiated infants and in none of the control infants. When normal CK-BB activity was used as a predictor of good neurologic outcome and elevated CK-BB as a predictor of subsequent neurologic abnormality, the outcome was predictable from the CK-BB activity in 17 of 22 cases (77%) and in 11 of the 12 survivors (92%). Eight of the 12 surviving infants had neonatal seizures and outcome was predictable from CK-BB activity in all cases. We conclude that serum CK-BB activity, especially when measured in cord blood and at six to 12 hours of life, correlates with neurologic outcome after severe asphyxia, and that measurement of CK-BB compares favorably with radionuclide and computerized tomographic scanning as a method of predicting neurologic outcome after asphyxia.

A comparative study of 99mTc and 131I in thyroid scanning

Thyroid scans performed with both 99mTc pertechnetate (99mTcO4) and (131I) were compared in 46 patients with palpable thyroid nodules to determine whether 131I scanning is any longer a necessary procedure. A discrepancy between the two types of scan existed in only three cases, in one of which the thyroid nodule showed uptake of 99mTcO4 but not of 131I. Subsequent surgery revealed a thyroid malignancy in this patient. In each of the other two discrepancies a nodule "cold" on 99mTcO4 scanning was apparently functioning on 131I scanning, and was found to be benign at surgery. As the convenience and lower radiation absorbed dose of 99mTcO4 patients compared with 131I make it a better scanning agent, it is recommended that 99mTcO4 scans of the thyroid be first nodules. If these nodules prove to be functioning equally with paranodular tissue, a 131I scan should also be performed to help exclude a possible thyroid malignancy.

The genome of orf virus: restriction endonuclease analysis of viral DNA isolated from lesions of orf in sheep

The purification of orf virus directly from scab material from clinical cases of orf in sheep and restriction endonuclease analysis of the viral DNA is described. Between 7 x 10(9) and 1.6 x 10(11) virus particles, and 0.7 to 22.8 micrograms of viral DNA could be recovered from 1g of scab material. Considerable heterogeneity was observed between different field isolates when restriction endonuclease digests of orf DNA were compared by gel electrophoresis. It was also shown, for two isolates, that these fragment patterns did not change after plaque purification and passage in cell culture. It is suggested that restriction endonuclease analysis of viral DNA offers a convenient method of identification of isolates of orf virus. The molecular weight of orf DNA was determined and found to be 88.8 x 10(6).

Creatine kinase isoenzymes in serum from cord blood and the blood of healthy full-term infants during the first three postnatal days

Isoenzymes of creatine kinase (ATP:creatine phosphotransferase; EC 2.7.3.2; CK) were measured by electrophoresis in serum from cord blood and skin-puncture blood taken from 45 healthy full-term infants during the first three postnatal days. Mean total CK activities (in U/L at 30 degrees C) were 185 in cord samples, 536 in samples taken between 5--8 h postnatally, 494 between 24--33 h, and 288 in the 72-100 h samples. Values for all three isoenzymes increased to a peak over this period, with the highest values generally being found in the samples taken 5--33 h after birth; the subsequent decline was most rapid for CK-BB. Serum CK isoenzymes in cord samples and those taken at 72--100 h in the 11 babies delivered by cesarian section did not differ significantly from those of babies delivered vaginally. However the postnatal increases in total CK, CK-MM, and CK-MB (but not in CK-BB) were significantly greater in those patients born by vaginal delivery. The reasons for the increases in CK isoenzymes after birth are not clear, but our results and reported studies on the ontogeny of CK suggest that CK-MB cannot be regarded as a "cardiac-specific" isoenzyme in the neonatal period.

Creatine kinase isoenzymes in serum from cord blood and the blood of healthy full-term infants during the first three postnatal days

Isoenzymes of creatine kinase (ATP:creatine phosphotransferase; EC 2.7.3.2; CK) were measured by electrophoresis in serum from cord blood and skin-puncture blood taken from 45 healthy full-term infants during the first three postnatal days. Mean total CK activities (in U/L at 30 degrees C) were 185 in cord samples, 536 in samples taken between 5--8 h postnatally, 494 between 24--33 h, and 288 in the 72-100 h samples. Values for all three isoenzymes increased to a peak over this period, with the highest values generally being found in the samples taken 5--33 h after birth; the subsequent decline was most rapid for CK-BB. Serum CK isoenzymes in cord samples and those taken at 72--100 h in the 11 babies delivered by cesarian section did not differ significantly from those of babies delivered vaginally. However the postnatal increases in total CK, CK-MM, and CK-MB (but not in CK-BB) were significantly greater in those patients born by vaginal delivery. The reasons for the increases in CK isoenzymes after birth are not clear, but our results and reported studies on the ontogeny of CK suggest that CK-MB cannot be regarded as a "cardiac-specific" isoenzyme in the neonatal period.

Further experience with computer-assisted diagnosis of diseases of the liver and biliary tree

Computer-assisted classification of disease has largely relied upon testing the diagnostic algorithm in the same population from which it was originally derived, as a means of validation. To evaluate the accuracy of a diagnostic program in which discriminant function analysis is used, we applied it to a separate population, selected by different criteria from those used to define the original case material on which the diagnostic program was based. We selected a group of 315 patients having abnormal values for alkaline phosphatase, bilirubin, or aspartate aminotransferase for further biochemical and immunological investigations. We used a computer program involving discriminant function analysis and classification procedures primed with the results of 10 tests obtained on each of 535 patients in a previous series to allocate those 173 new patients who had diseases of the liver or biliary tree into one of 13 disease groups. The classification was less accurate than was the case in previous cross-validation studies. We developed new discriminants with the new case material, using the same group of tests, and when cross-validation was performed, overall accuracy was greatly improved. These experiences point to the powerful influence of group selection upon computer-assisted diagnostic procedures, and the hazards of applying to one clinical population discriminant functions derived from a different population.