Development of radioimmunoassays for human erythropoietin using recombinant erythropoietin as tracer and immunogen

Since the estimation of erythropoietin (EPO) by radioimmunoassay (RIA) has been limited by the availability of highly purified urinary (U) human (Hu) EPO, we investigated the use of recombinant (R)-HuEPO as a replacement for U-HuEPO in the preparation of 125I-tracer and high affinity antisera. In each of two validated RIAs developed using U-HuEPO-derived reagents, dose-response lines and potency estimates for samples were compared when 125I-U-HuEPO and anti-U-HuEPO antisera were sequentially replaced to give assay variants using R-HuEPO-derived reagents. Two U-HuEPO preparations, the 2nd International Reference Preparation and CAT-1, and R-HuEPO were variously used as standards. The samples tested included clinically relevant human sera and partially purified preparations of U-HuEPO and R-HuEPO. In each RIA and for each assay variant tested, samples gave dose-response lines whose slopes did not differ significantly from that of the standard. For each of the two variant RIAs, potency estimates for any sample were consistent and, where examined, RIA potency estimates agreed with in vivo bioassay determinations. These results, obtained independently in two laboratories, indicate that RIAs having appropriate specificity and sensitivity for the estimation of EPO in clinical samples can be developed using reagents derived from R-HuEPO.

Binding the elderly: a prospective study of the use of mechanical restraints in an acute care hospital

Little information exists on the use of mechanical restraints among nonpsychiatric inpatients. This prospective study evaluates their use among consecutive medical and surgical admissions to an acute care hospital. Daily direct observation of patients and hospital record review provided data on potential predictors of restraint, reasons for their application, complications, and outcome. Cox regression analysis was used to calculate relative risk of restraint while adjusting for duration of hospitalization as well as other variables. Restraints were applied to 37 (17%) of the 222 study patients. Restrained patients were eight times more likely to die during hospitalization (24% v 3%; P less than 0.01). Abnormal mental status exam, diagnosis of dementia, surgery, and presence of monitoring and support devices (eg, intravenous lines) were statistically significant independent predictors of restraint. Mechanical restraint is a common occurrence among nonpsychiatric inpatients particularly those with impaired mentation, requirement for surgery, or intensive medical intervention. Identification of medical and surgical patients at risk for restraint may reduce the use of these devices by concentrating surveillance and prevention on this group.

Characterization and biological effects of recombinant human erythropoietin

Human recombinant erythropoietin (rHuEPO) has been purified to apparent homogeneity and compared to purified human urinary erythropoietin (EPO). Both the purified natural and recombinant EPO preparations were characterized in a competition radioimmunoassay (RIA), the exhypoxic polycythemic mouse bioassay, in vitro tissue culture bioassays using bone marrow cells, and by Western analysis. In the immunological and biological activity assays, the rHuEPO shows a dose response which parallels that of the natural hormone. By Western analysis, the recombinant and human urinary EPO migrate identically. Administration of rHuEPO increases the hematocrit of normal mice in a dose-dependent manner. Additionally, the rHuEPO is able to increase the hematocrit of rats made uremic as a result of subtotal nephrectomy. In summary, by all criteria examined, the rHuEPO is biologically active and equivalent to the natural hormone.

Bone disease in prolonged parenteral nutrition: osteopenia without mineralization defect

A metabolic bone disease characterized by a mineralization defect, low plasma 1,25(OH)2D, and hypercalciuria has been described in patients receiving prolonged total parenteral nutrition (TPN). Because the practice of TPN differs from center to center, we investigated 13 home TPN patients to determine whether they had similar or different bone abnormalities. They had received TPN for a mean period of 51 +/- 38 mo. Bone pain occurred in six patients and two had multiple vertebral and rib fractures (with trauma in one patient). Bone pain was mild to moderate and not incapacitating. Bone histomorphometry showed reduced bone volume, reduced osteoid with normal resorption and calcification rates. These abnormalities were associated with hypercalciuria, but the plasma levels of 1,25(OH)2D were normal. Abnormalities in bone metabolism in this group of patients suggest a fundamental decrease in bone matrix-formation rather than a mineralization defect as the underlying mechanism.

Evaluation of a blood-free, charcoal-based, selective medium for the isolation of Campylobacter organisms from feces

A blood-free, charcoal-based selective medium (CSM) consisting of a Columbia agar base, activated charcoal (4 g/liter), hematin (0.032 g/liter), sodium pyruvate (0.1 g/liter), cefoperazone (32 mg/liter), vancomycin (20 mg/liter), and cycloheximide (100 mg/liter) supported the growth of Campylobacter jejuni and C. coli with colony counts equivalent to those obtained on antibiotic-free horse blood agar. CSM was compared to Skirrow medium (SKM) for the recovery of C. jejuni and C. coli from stools of patients with diarrhea, the media being incubated for 2 days under reduced oxygen tension at 43 degrees C. These campylobacters were isolated from 35 (2.9%) of 1,227 stools tested (29 on both media, 5 on CSM alone, and one on SKM alone). Whenever C. jejuni and C. coli were recovered, growth was pure on 29 CSM cultures (85%), but on only 11 SKM cultures (37%). Complete suppression of "contaminating" flora occurred in 704 CSM cultures (57%) compared with 426 SKM cultures (35%). CSM more effectively suppressed contaminating pseudomonads, gram-positive organisms, and yeasts than did SKM; both media failed to suppress members of the family Enterobacteriaceae in about a quarter of the samples. Studies on 20 representative Enterobacteriaceae contaminants showed that susceptibility to cefoperazone and growth on CSM were markedly dependent on inoculum size; 12 strains were inhibited by cefoperazone (32 mg/liter) at inoculum sizes of 5 X 10(2) and 5 X 10(4) but not 5 X 10(6) organisms, indicating that the frequency of contaminants on CSM could probably be reduced further by ensuring that stools were not inoculated too heavily on CSM. Our findings confirm that charcoal is an effective substitute for blood in media for growing campylobacters, and that CSM is a highly effective blood-free selective medium for isolating C. jejuni and C. coli from stools.

Retinal vasculitis associated with HLA DR4. Brief definitive report

Inflammation of retinal blood vessels may be associated with a variety of systemic immune diseases. Despite the fact that a number of immunological abnormalities have been reported in patients with retinal vasculitis (RV), previous studies have failed to demonstrate an immunogenetic predisposition to this disease. HLA A, B, and DR locus typing of 25 patients (14 females) with well-characterized RV revealed an increased incidence of HLA DR4 (corrected p value = 0.04, relative risk = 3.5). The HLA DR4 antigen was increased in patients with both central and peripheral RV as well as in patients with idiopathic disease (14 patients) and in those with Behcet's syndrome (8 patients). The results of this study indicate that immune response genes may be involved in the pathogenesis of RV.

Investigations of melatonin secretion in man

Overnight melatonin secretion shows substantial and significant intraindividual stability and large interindividual variation. Melatonin concentrations obtained between 1 and 5 a.m. significantly correlate with overall melatonin secretion (expressed as the area under the curve) while a single determination of serum melatonin does not adequately reflect the entire night secretion. Secretion correlates positively with "neuroendocrine responsiveness" (rating responses in other neuroendocrine challenge tests) and there is trend for negative correlation with age. In volunteers the administration of the usual therapeutic dose of lithium did not alter the overnight melatonin secretion. However, there was an elevation of isolated secretory values at the early morning timepoints. In comparison with volunteers, lithium administration tended to reduce the overnight melatonin secretion in bipolar patients, however, the difference did not reach statistical significance.

Elevated serum parathyroid hormone, calcitonin, and 1,25-dihydroxyvitamin D in lactating women nursing twins

The roles of vitamin D, calcitonin, and parathyroid hormone in calcium metabolism during lactation may be more evident in women secreting very large amounts of milk for a number of months, as in mothers nursing twins. We report significant increases in serum concentrations of parathyroid hormone, calcitonin, and 1,25(OH)2 vitamin D in mothers nursing twins compared to mothers nursing single infants. Serum concentrations of calcium actually increased in both groups during lactation. Maternal intakes of calories, calcium, and phosphorus were significantly higher in mothers nursing twins. Thus, mothers nursing twins were able to compensate for higher calcium losses in breast milk by increased dietary intakes of calcium as well as increased serum concentrations of parathyroid hormone, calcitonin, and 1,25(OH)2 vitamin D.

Effects of lithium, nortriptyline and dexamethasone on insulin sensitivity

The effects of lithium, dexamethasone, nortriptyline and their combinations on insulin sensitivity, expressed as a drop of plasma glucose in response to insulin challenge, were investigated in healthy volunteers. Short-term (three weeks) lithium treatment did not appear to exert any influence on the insulin sensitivity. Dexamethasone administered alone (2 mg given 57 hours prior to the test) had no effect on the insulin sensitivity of drug-free healthy subjects. However, after three weeks of lithium treatment the dexamethasone premedication resulted in slight flattening of glucose response to insulin in the same persons. Nortriptyline administered for three weeks to healthy volunteers, pretreated with dexamethasone, increased insulin sensitivity. These findings may have clinical implications regarding the treatment of depressed diabetic patients, and may provide information about the regulation of insulin sensitivity.

An accurate and reproducible absorptiometric technique for determining bone mineral content in newborn infants

At the Bone Mineral Laboratory of the University of Wisconsin a microcomputer-based digital read-out system was designed specifically for determining bone mineral content (BMC) and bone width (BW) in newborn infants with the following features: (1) high accuracy and precision; (2) high reproducibility in vivo; (3) direct read-out of BMC and BW; (4) automatic data calibration; and (5) use of a low activity [125I] source (less than 50 mCi). BMC and BW were determined on the left radius on a series of 114 newborn infants of all gestational ages and a curve for intrauterine bone mineral content extrapolated from the data. Accuracy of the photon absorptiometric system was assessed by measuring BMC on a series of nine small bone sections (29-212 mg/cm) and confirmed by subsequent ashing of these bone sections (r = 0.99). Short-term precision (weekly, coefficient of variation 1.7%) and long-term precision (monthly, coefficient of variation 2.1%) for measuring BMC were determined by multiple determinations on a four-chambered bone phantom calibrated with the bone sections. Immediate reproducibility (without repositioning the arm) for the 4-6 scans performed for each determination of BMC and BW was good with a mean coefficient of variation of 3.9% for BMC and 3.6% for BW. In 84 infants, repositioning error was determined by repeating the measurement of BMC and BW after repositioning the arm. The correlation coefficients between measurements before and after repositioning the arm were 0.97 for BMC and 0.95 for BW. BMC correlated well with gestational age (r = 0.92), birth weight (r = 0.89) and bone width (r = 0.92). BW also correlated with gestational age (r = 0.84) and birth weight (r = 0.85). A multiple linear regression analysis of BMC versus BW, gestational age, and birth weight was done. The correlation coefficient between the predicted BMC from these variables and measured BMC was 0.95. Photon absorptiometry can be used with high accuracy, precision, and reproducibility in vivo in newborn infants. BMC correlates with gestational age, birth weight, and bone width.

Changes in dimensions of large cancellous bone specimens during histological preparation as measured on slabs from human femoral heads

Distortion of the dimensions of large cancellous bone specimens during all stages of histological processing and cutting of paraffin sections in various directions was measured on Xerograms taken from slabs and then sections from human femoral heads. Although some shrinkage in both width and height of the specimens occurred at every stage of the histological preparation, the main shrinkage (about 6%) occurred during the embedding process, and mainly in the cutting of the sections (10-27%, depending on the direction the knife was approaching the specimen). The shrinkage of cancellous bone tissue during histological preparation appears to be a constant factor, but its magnitude during the individual stages of the preparation can be predicted. For the quantitative measurements a comparison of two Xerograms--one taken from the original fresh bone slab and the other from the final stained section--would reveal the exact extent of the tissue shrinkage.

Induced basal normoglycemia and altered platelet aggregation in non-insulin-dependent diabetes

Non-insulin-dependent diabetic subjects had abnormally raised in vitro platelet aggregation rates to collagen or ristocetin when thought to be "well-controlled" on diet alone but shown to have raised basal plasma glucose levels. Basal normoglycemia, induced with either ultralente insulin or chlorpropamide, was associated with a significant reduction of the enhanced platelet aggregation rates to normal. Some sulfonylurea drugs have been reported to have specific anti-platelet aggregatory properties, but the degree of plasma glucose control is probably more relevant.

Serological and biochemical analysis of the PlA1 alloantigen of human platelets

A solid phase platelet antibody assay has been developed which rapidly and sensitively detects PlA1 antibodies. The three-step assay is performed by: (1) adhering platelets to the wheels of a microtitre plate, (2) incubating the platelets with test serum, and (3) adding radiolabelled Staphylococcal protein A which binds to the Fc domain of IgG antibodies. Immune reactions are detected by overnight autoradiography. Characterization of the PlA1 antigen was performed by using PlA1 antisera in immune precipitation assays. A 90 000 dalton molecular weight species was precipitated from PlA1 positive human and dog platelets.

A technique for cutting slices from femoral heads and other awkwardly shaped bones

For cutting thin, parallel slices from round and other awkwardly shaped bones, we have developed an useful aid by modifying the Microslice II cutting saw primarily designed for geological or metallurgical purposes. To ensure a good grip of the bone, the specimen is embedded in a bolus of wax in a cylindrical container and is advanced along the container by a screw plunger toward the cutting blade of the machine. It is thus possible to cut even from awkwardly shaped bones 2-30 mm thick parallel slices suitable for decalcified or undecalcified histological sections and also for radiodensitometry or quantitative microradiography.

Osteonecrosis in patients with malignant lymphoma: a review of twenty-five cases

A retrospective study of 25 patients with malignant lymphoma who had osteonecrosis of either the femoral or humeral head(s) was undertaken. The common factor present among all patients was the administration of intermittent steroid-containing combination chemotherapy. Seventeen Hodgkin's disease patients received chemotherapy predominantly consisting of an alkylating agent, vincristine, procarbazine, and moderate amounts of prednisone. The non-Hodgkin's lymphoma patients were on various moderate dosage steroid-containing protocols, except three who received prolonged high-dose steroid-containing chemotherapy regimens. Sixteen of the 17 Hodgkin's disease patients and five of the eight non-Hodgkin's lymphoma patients received radiotherapy to the bones that subsequently developed osteonecrosis. Two of the three non-Hodgkin's lymphoma patients who were not irradiated were treated with high-dose steroid-containing chemotherapy regimens. Symptoms developed in patients 12 months and 32 months after completion of chemotherapy and radiotherapy, respectively. Osteonecrosis was a long-term complication of treatment between 1970 and 1979 and occurred in 1.6% of the Hodgkin's disease and 0.12% of the non-Hodgkin's lymphoma patients treated. The authors conclude that the patients at highest risk for this complication are those who receive both radiotherapy to the affected bone(s) and intermittent steroid-containing multiple drug chemotherapy.

Marrow transplantation for juvenile osteopetrosis

Two children with the juvenile form of osteopetrosis were treated with marrow transplants from their HLA identical siblings. Following transplantation each child exhibited extensive bone reabsorption with a marked augmentation of osteoclastic function attributable to donor osteoclasts, including remodeling of bone with expansion of intramedullary hematopoiesis and correction of associated abnormalities of thymic factor and natural killer cells. Osteopetrosis ultimately recurred in one patient in whom engraftment of donor hematopoietic elements was not achieved. Our studies indicate that marrow transplantation will correct osteopetrosis but that permanent reconstitution necessitates sustained engraftment of marrow precursors of cells with osteoclastic activity.

Ewing's sarcoma: ten-year experience with adjuvant chemotherapy

Since May 1970, 67 consecutive patients with primary (nonmetastatic) Ewing's sarcoma were treated with adjuvant chemotherapy (CT) in addition to radiation therapy (RT) or surgery for the primary tumor. The first 19 patients were treated with four-drug sequential CT (T-2). The second protocol was a seven-drug induction combination CT (T-6) followed by T-2 maintenance CT; in both protocols CT was continued for 18 months. The current protocol (T-9) consists of combination CT given continuously for a period of 9 months. Of the entire group of 67 patients, 47 (70%) had axial and proximal lesions (pelvis, spine, rib, humerus, and femur) and 20 (30%) had distal lesions (forearm, leg, and foot); 53/67 (79%) are surviving free of disease 12--118 months (median 41 months) from the start of treatment. Fifteen of 23 (65%) patients with axial lesions, 19/24 (79%) patients with proximal lesions, and 19/20 (95%) patients with distal lesions are free of disease. Disease-free survivors include 28/39 (72%) male patients and 25/28 (89%) female patients. Thirty-four patients had RT, and 33 had surgery or surgery and RT, in addition to chemotherapy, for local treatment. The disease-free survival rate was 76% in the RT group and 82% in the surgery group; failure in the RT group was attributable to local recurrence in 7/34 (21%) patients. Recent experience with T-9 CT has demonstrated that CT given prior to RT or surgery can cause a great reduction in the size of the primary tumor while allowing the pathologically-eroded bone to heal prior to the initiation of RT; this also allows the high-risk patient with an axial primary (pelvis or spine) to tolerate the aggressive CT needed to prevent distant metastases. In addition to dramatically increasing survival in patients with Ewing's sarcoma, combination CT has helped achieve permanent local control. The superior survival rates for all sites of primary tumor are attributable to the early use of aggressive combination CT.

The use of cross-leg flap in malignancy: realization of a potential complication

We present a case of recurrent myxoid fibrosarcoma presumed to have spread to the contralateral leg by means of cross-leg flap procedure. In the era of free flap transfer, musculocutaneous flaps and the recent cross-leg musculocutaneous flap, the cross-leg flap remains a valuable technique for the reconstructive plastic surgeon. However, it should not be considered in reconstruction after resection of a malignant tumor.

Human monoclonal antibody against Forssman antigen

Hybrid cells formed between human lymphocytes and mouse myeloma cells produce human immunoglobulin in culture. Stable antibody-producing cell lines can be isolated after multiple cycles of low-density passage, cloning, and continued selection for immunoglobulin production. The origin and characteristics of a hybrid of human and mouse cells is described. This hybrid produces high concentrations (8.3 micrograms per milliliter) of human immunoglobulin M reactive with the terminal disaccharide of the Forssman glycolipid. These findings point to the potential use of human-mouse hybrid cells as a source of human monoclonal antibodies for therapeutic and diagnostic purposes.

Bone scanning: its lack of value in the follow-up of patients with breast cancer

Three hundred and fifty-four women with primary operable breast cancer had a bone scan performed within 6 weeks of a simple mastectomy. Eight (2.3 per cent) were positive, but 7 of these patients had radiological evidence of bony metastases. Follow-up bone scans 1 year postoperatively on 278 patients showed only 12 (4.3 per cent) positive, and of these, 9 had other radiological evidence of metastatic disease. At 2 years postoperatively there were 13 (9.2 per cent) positive bone scans amongst 141 patients. Only 2 of these 13 had no other evidence of metastases. Although a bone scan is a useful investigation in patients with bone pain, there is no place for routine bone scanning in either the staging or follow-up of women with operable breast cancer.

Glycine and experimental spinal spasticity

Spasticity may result in part from segmental spinal disinhibition. We determined the content and specific activity of glycine (the putative neurotransmitter thought to mediate spinal postsynaptic inhibition) and serine (the probable precursor of glycine) in feline spastic spinal cord following the intra-aortic administration of two labelled precursors of glycine--14C-D-glucose and 14C-L-serine. The specific activities of both glycine and serine were significantly reduced in the ventromedial, central, and dorsal spinal gray matter in spastic animals. Glycine content remained at control values but serine content increased in spastic spinal cord. This study suggests that glycine turnover decreases in spasticity, owing to its diminished release, and supports neurophysiologic evidence of a decrement in postsynaptic inhibition.

The effect of altering self-descriptive behavior on self-concept and classroom behavior

This research examined the impact of operant reinforcement of positive self-descriptive behavior on the self-concepts and classroom behavior of 60 fifth-grade students. Three groups of 10 male and 10 female low self-concept students wrote a series of eight essays describing their school performance. The first group (P) received written reinforcement for positive self-descriptions of their school performance. The second group (G) received an equal number of reinforcements for general statements. The third group (C) received no reinforcement for written statements. Three areas of self-concept were measured with the Primary Self-Concept Inventory: personal-self, social-self, and intellectual-self. A frequency count was also made of nine classroom behaviors thought to be influenced by self-concept. The P group displayed increases in the frequency of positive self-descriptive statement and in intellectual self-concept but no changes in personal self-concept, social self-concept, or the nine classroom behaviors. The G and C groups showed no change in self-description, self-concept, or the nine classroom behaviors.

Variation in the molecular size of the DNA from closely related strains of type I herpes simplex virus

We have investigated the comparative genome size of five strains of HSV type 1 (HSV-1). Two of these strains have a common origin and differ in their plaque morphology on HeLa cells, one strain is a wild type isolate, and two others are established laboratory strains. All strains show high sequence homology based on the melting behavior of heteroduplexes. The greatest sequence divergence between any two strains was found to be no more than 10%. There are real differences in the size of the genomes of these strains of HSV-1 as measured by electron microscopy. The shortest and largest genomes measured differ in size by 10%, however, the size of the genomes of all strains are within 5% of a median valve of 87-88X106.

Long-term effects of chondrocyte death on rabbit articular cartilage in vivo

The effects of freezing localized areas of rabbit articular cartilage in vivo were studied at two to twelve months morphologically (gross and microscopic examination, including scanning electron microscopy), histochemically (toluidine blue and safranin O), and metabolically (35S uptake). Up to six months the frozen cartilage was intact but appeared to be dead, as shown by the absence of stainable chondrocytes, severely decreased acid mucopolysaccharide content, and absence of significant uptake of 35S. At twelve months fibrillation and softening were evident, clusters of new chondrocytes with surrounding acid mucopolysaccharides were visible microscopically, and scanning electron microscopy revealed an irregular pattern of collagen fibers which were larger than normal, of varying thickness, and broken in some areas. These changes resembled those seen in degenerative joint disease.

The 11-oxygenation index in pregnancy: tentative evidence for decreased foetal adrenocortical enzyme activity at parturition

The urinary 11-oxygenation index has been measured throughout pregnancy in 25 women. The index rose steadily throughout pregnancy. At about 35 weeks gestation it rose rapidly, reached a peak just before parturition and rapidly fell to normal thereafter. Statistical analysis indicated that there might be differences in the index levels between women who delivered spontaneously and women in whom induction was necessary. It is suggested that this rise in the index reflects a foetal adrenocortical enzyme inactivity, leading to an increased secretion of cortisol precursors into the maternal circulation at term, which may be involved in the processes of parturition.