Correlative electrophysiological and behavioral evaluation following L5 lesions in the cat: a model of spasticity

The present work developed an animal model of hindlimb spasticity by analyzing the electrophysiological and behavioral consequences of L5 spinal cord lesions in cats. In chronically lesioned animals (1 to 6 months), the L7-S1 dorsal roots were stimulated and evoked potentials were recorded from hindlimb flexor and extensor motor nerves. Following lateral hemisection, the monosynaptic responses were 2-5 times larger (for voltage-time integral and for amplitude) on the ipsilateral side than those from the contralateral side or from control animals. Half-widths, rise-times, and latencies of the monosynaptic responses were the same on both sides. Behavioral signs of spasticity, including hypertonia and increased deep tendon reflexes, were displayed from the ipsilateral hindlimb following lateral hemisection. With lateral hemisection or with extensive dorsal quadrant lesions, hopping and proprioceptive placing reflexes were abolished; these behavioral observations impart functional significance to physiological and anatomical studies of a mid-lumbar center considered to be important for movement control. The present model represents the first demonstration of a statistically significant correlation between electrophysiological and behavioral observations of spasticity for animals with a lateral hemisection. These correlations demonstrate the utility of behavioral screening of animals for subsequent neurophysiological analyses. This facilitates the investigation of cellular events underlying spasticity and of strategies for its relief with tissue repair techniques affecting local circuitry involved in spasticity.

Immunohistochemical staining for ferritin in neuroblastomas

Immunohistochemical staining for ferritin was examined in 35 neuroblastomas from 27 children and compared with serum ferritin levels. All but two of the patients presented with advanced (stages III and IV) disease, and the adrenal was the most common primary site (20/27, 74%). Immunostaining was positive in only one of 14 tumour biopsies taken at the time of diagnosis (7%), but eight of 21 neuroblastomas (38%) marked for ferritin after chemotherapy. No consistent association was established between tumour- and serum-associated ferritins in the untreated or treated groups. Ferritin staining in treated neuroblastomas was usually more marked in partly differentiated tumour cells. The increased frequency of ferritin positive neuroblastomas after chemotherapy appeared to be associated with large local accumulations of ferritin and haemosiderin within the treated tumours, and (probably) with the blood transfusions which these children received.

Crossed and uncrossed projections to cat sacrocaudal spinal cord: II. Axons from muscle spindle primary endings

The terminal fields of primary afferent fibers from tail muscle spindle primary endings were mapped within cat sacrocaudal spinal cord (S3-Ca7), using intra-axonal recording and horseradish peroxidase staining techniques. We sought to determine the ipsilateral and contralateral projection patterns and to relate these to the fibers' muscles of origin. Fifty-three group Ia fibers were successfully stained. Segmental collaterals originated from either the ascending or descending branch within the dorsal columns. Collaterals coursed rostromedially within the dorsal columns and traversed the medial aspect of the dorsal horn. Ipsilateral terminations were similar for all fibers. Within the ventral horn, boutons were consistently observed in the medial or central portions of lamina VII. In lamina VIII, a variable number of boutons was seen on fine branches emerging from larger fibers coursing ventrally. Clusters of terminals were plentiful in the regions of motoneurons, i.e., lamina IX and the nucleus commissuralis. Terminals were found in the adjacent white matter. In addition to ipsilateral terminations, some group Ia fibers (20 of 53) had collateral branches that crossed ventrally to the central canal, terminating within the midline ventral gray commissure and/or the contralateral ventral horn. Crossed projections always originated in medial (dorsal or ventral), but not lateral, muscles of the tail. These data suggest that ipsilateral projections of group Ia fibers make connections on sacrocaudal motoneurons, on neurons mediating segmental reflex functions and on neurons conveying ascending information. It is speculated that crossed and uncrossed connections between group Ia fibers from medial muscles and bilateral dendritic trees of motoneurons subserve synchronized co-contraction of synergistic muscles located on the two sides of the body, such as with dorsal or ventral flexion of the tail. Group Ia projections from lateral muscles, that are entirely ipsilateral, would be involved with lateral movements of the tail.

Comparative phenotypes in rhabdomyosarcomas and developing skeletal muscle

The morphological and immunohistochemical phenotypes of 51 rhabdomyosarcomas from young people have been described and contrasted with phenotypes in developing skeletal muscle from 20 fetuses and neonates. The tumours express markers in a cumulative and consistent sequence--vimentin, desmin, fast myosin, myoglobin--which evolves pari passu with morphological differentiation and follows the same pattern found in normal myogenesis. Changes in immunohistochemical phenotype are documented in residual and recurrent tumours excised after chemotherapy. The presumptive rhabdomyoblastic nature of some primitive tumours, marking with vimentin alone, is discussed.

Growth in children following kidney transplantation

Growth was assessed in children following 128 separate kidney transplants using a generalized growth curve multivariate analysis. The height standard deviation score was the dependent variable. Time since transplant, prednisone dosage, and creatinine clearance were the independent variables. For the purposes of comparison patients were grouped according to sex, race, age at transplantation, initial allograft function, acute rejection episodes and the use of cyclosporin A. Patient's height standard deviation scores tended to increase negatively after transplantation. However, children who received transplants before their 7th birthday, with initial allograft function greater than 60 ml/min per 1.73 m2, exhibited "catch-up" growth. Height standard deviation scores positively improved in males but not in females, as prednisone dosage was decreased. Height standard deviation scores became more negative as renal function decreased after transplantation. Changes in renal function produced the greatest effect upon height in black children, children less than 7 years, and males.

A comparative study of immunohistochemical staining for neuron-specific enolase, protein gene product 9.5 and S-100 protein in neuroblastoma, Ewing's sarcoma and other round cell tumours in children

A comparative study of immunohistochemical staining for neuron-specific enolase (NSE), protein-gene product 9.5 (PGP 9.5) and S-100 was made in 71 undifferentiated round cell tumours from 65 children using formalin-fixed tissues and a standard alkaline phosphatase-anti-alkaline phosphatase method. All of 29 neuroblastomas marked for NSE and 27 for PGP 9.5; staining was diffuse and usually strong in all tumour elements, irrespective of the degree of differentiation. Patterns of staining remained consistent in primary, recurrent and metastatic tumours and were not modified by previous chemotherapy. S-100 staining was weak and confined to cell processes and schwannian elements in less than half of the tumours studied. Two primitive neuroectodermal tumours both stained strongly for NSE and PGP 9.5. Staining for NSE was observed in single maturing cells in 3/12 rhabdomyosarcomas and in tubular elements in 2/4 Wilms' tumours; primitive rhabdomyoblasts and undifferentiated renal blastema were negative; seven lymphomas were negative. Six of 17 skeletal Ewing's sarcomas showed light to moderate cytoplasmic staining for NSE and PGP 9.5. The site, histology and clinical course of these marker-positive Ewing's sarcomas showed no distinctive features. Staining for PGP 9.5 is a useful additional marker for neural differentiation in round cell tumours.

Upper-normal prediction limits of lymphocyte counts for cattle not infected with bovine leukemia virus

A study was conducted to develop valid estimates of lymphocyte count (LC; cells per microliter) of individual, clinically normal dairy cattle. Estimated weighted regression was used on repeated measures of individual LC to examine 6 models predicting LC as a function of age in cattle not infected with bovine leukemia virus. The generalized growth curve model of analysis of variance was used to estimate intercepts, slopes, and prediction limits for the models and to compare the LC-to-age relationship between Holstein and Guernsey breeds. The best-fitting model (P = 0.0001) with the narrowest prediction interval was LC = 4,414.4 - 84.6X, where X = (age -48) if age less than or equal to 48 months, and X = 0 if age greater than 48 months, and 163.6 and 8.1 are the SE of the estimates, respectively. Upper one-sided 95%-predicted normal LC tended to be higher than estimates derived from traditional hematologic keys that use confidence limits of mean LC. Difference was not found in the LC-to-age relationship between the Holstein and Guernsey cattle (P = 0.67). Results of this study provided estimates of normal LC that are more specific in diagnosing lymphocytosis in individual cattle.

Low incidence of ras oncogene activation in human squamous cell carcinomas

Activation of the ras gene family by point mutation at codons 12, 13 and 61 has been demonstrated in up to 20% of unselected series of human tumours. The present study was carried out to assess the incidence of ras activation in 37 squamous cell carcinomas of the head and neck, seven squamous cell carcinomas of the skin and eight squamous carcinoma cell lines. Oligonucleotide probes and the polymerase chain reaction were used on DNA extracted from achival paraffin embedded material. Mutations in codon 12 of the Harvey ras gene was found in a carcinoma of the larynx and a carcinoma of the lip, both of which had received prior irradiation. A cell line (LICR-LON-HN8) established from the same laryngeal cancer showed the same mutation. This study indicates that there is a low incidence of ras mutation in human squamous cell carcinomas and that activation of this family of genes is probably not a common factor in the development of this group of tumours.

Effects of birth weight and sociodemographic variables on mental development of neonatal intensive care unit survivors

Neonatal intensive care unit survivors (N = 494) from 10 tertiary care centers were evaluated over the first 4 to 5 years of life to determine the relative contributions of birth weight and sociodemographic factors to mental development. Six sociodemographic factors were studied: sex, race, family income, and mother's marital status, age, and educational level; the last five factors also are known to be associated with premature birth. Mental development was measured with the Bayley Scales of Infant Development (12 to 24 months) and the Stanford Binet Intelligence Test (4 to 5 years). Each factor's influence was assessed by multivariate analysis. Birth weight had limited long-term implications; at 4 to 5 years, only infants with birth weights less than 1000 gm had significantly lower scores than those in other birth weight categories. Sociodemographic variables had a greater impact on mental development, with age-dependent differences found between nonwhite and white children and between children with mothers of low, medium, and high educational levels.

A longitudinal study of the cognitive function of children with renal failure

Fifty-six children with chronic renal failure who either received a kidney transplant, were hemodialyzed or peritoneally dialyzed, or who were being medically managed were given a series of neuropsychological tests every 6 months for a total of four testing sessions. Each child was matched by age, sex, and race to healthy children who received the same sequence of tests. The performance of each treatment group was compared with their controls longitudinally, using a repeated measure analysis of variance. In general, renal subjects performed at lower levels than their controls on tasks of verbal ability, visual perception, memory and visual motor skills. Visual motor performance was the most clinically affected. When compared with controls, the renal subjects did not improve as much or actually deteriorated on some measures of memory and learning skills.

Association between renal function and cognition in childhood chronic renal failure

Forty-five children with renal failure who were either being medically managed, receiving dialysis (hemodialysis or continuous ambulatory peritoneal dialysis) therapy or who had received successful kidney transplants were longitudinally examined on multiple neuropsychological measures. A variety of medical parameters was also obtained at each time of testing. The neuropsychological variables were correlated with the medical variables using the repeated measures regression analysis method. There were associations between levels of renal function, short-term memory and list learning. Other neuropsychological variables did not in general correlate with the medical parameters consistently for all ages at the time of initial testing. Verbal performance decreased with increasing duration of renal failure in 6- to 11-year-olds and immediate recall decreased with increasing percentile rank of systolic blood pressure in 16- to 18-year-olds.

Expression of desmin and myoglobin in rhabdomyosarcomas and in developing skeletal muscle

Immunohistochemical staining for desmin and myoglobin was investigated in 35 rhabdomyosarcomas from young people and in skeletal muscle from 16 human fetuses of known gestational age. Twenty-nine of the rhabdomyosarcomas expressed desmin but six undifferentiated or poorly-differentiated tumours were desmin negative. Of the desmin positive cases, most undifferentiated or poorly-differentiated sarcomas expressed desmin alone (12/35). Tumours with increasing rhabdomyoblastomic differentiation co-expressed myoglobin (9/35) and well-differentiated examples also contained cross-striations (7/35). Skeletal muscle from fetuses aged 8 weeks or less consisted mainly of primitive desmin negative round cells. As the cells began to differentiate they quickly expressed desmin and, at approximately 10 weeks, myoglobin was expressed and cross-striations were seen. The combined results strengthen the view that desmin (within a strictly defined context of round cell tumours in young people) is a reliable marker for rhabdomyoblastic differentiation. Support is also given to the notion that very primitive rhabdomyosarcomas may be desmin-negative, although the difficulties of establishing firm diagnoses for some of these tumours is emphasized.

Effect of birth weight, race, and sex on survival of low-birth-weight infants in neonatal intensive care

Survival for low-birth-weight infants has traditionally been analyzed by birth weight categories spanning considerable ranges of weight. We developed a finer description of survival rates to allow estimation of survival percentages for infants of any specific birth weight between 500 and 2500 gm. Our sample consisted of 16,183 infants treated in tertiary neonatal intensive care between 1980 and 1987. Their survival data were analyzed by 50 gm increments between 500 and 2500 gm, and a continuous survival curve was constructed by log linear regression methods. Mortality differences between males and females and blacks and whites were analyzed. Survival for females was higher than males between 500 and 1500 gm and higher for blacks than whites between 650 and 1500 gm. Between 1500 and 2500 gm, no significant effects of birth weight, race, or sex were observed, with survival remaining stable at approximately 95% across all combinations of variables.

Chloralose alters both basal hemodynamics and cardiovascular responses to alveolar hypoxia in chronically instrumented, spontaneously breathing lambs

We studied the effects of chloralose anesthesia on the basal hemodynamic state and on the cardiovascular response to alveolar hypoxia in chronically instrumented, spontaneously breathing lambs, compared with responses to the saline vehicle. Chloralose significantly increased heart rate (23%), mean systemic arterial pressure (11%), systemic vascular resistance (21%), mean pulmonary arterial pressure (23%), and pulmonary vascular resistance (46%) (n = 30, p less than 0.05, ANOVA). These changes were unrelated to baseline tone of the circulation, cardiac output, mean left atrial pressure, or physiologically important changes in arterial blood gas tensions. In addition, chloralose-treated lambs had increased heart rate, systemic vascular resistance, and pulmonary vascular resistance compared to controls during alveolar hypoxia (13-15% FiO2). Importantly, chloralose-treated lambs did not increase their cardiac output during alveolar hypoxia as did control lambs. During hypoxia, systemic vascular resistance remained elevated in chloralose-treated lambs, but declined in control lambs. Chloralose has been recommended as an ideal anesthetic agent for cardiovascular experimentation. Our data suggest that chloralose-induced alterations in basal hemodynamics and in cardiovascular responses to alveolar hypoxia represent an uncontrolled variable in acute experimental studies. Complex cardiovascular alterations caused by anesthesia should be considered in experimental design.

Cyclooxygenase blockers inhibit ethanol-induced pulmonary vasoconstriction in lambs

We investigated the mechanism of ethanol-induced pulmonary vasoconstriction in lambs, by a pharmacological approach. We chronically instrumented 28 lambs to determine whether phentolamine (alpha-block), propranolol (beta-block), promethazine and cimetidine (H1- and H2-block), high-dose indomethacin, or low- and high-dose meclofenamate (cyclooxygenase block) altered the vasoconstriction. Ethanol alone increased pulmonary vascular resistance from 0.14 to 0.49 Torr.ml-1.kg-1.min (U). Only indomethacin (7-8 mg/kg po) and high-dose meclofenamate (7-8 mg/kg iv) abolished the pulmonary vascular response to ethanol infusion. Pulmonary vascular resistance was 0.14 U after ethanol plus indomethacin and was 0.2 U after ethanol plus high-dose meclofenamate (P = NS vs. base line). Low-dose meclofenamate (2 mg/kg) attenuated the vasoconstrictor response. Systemic vascular resistance increased moderately after ethanol and had a similar pattern of inhibition by cyclooxygenase blockade. Cardiac output and heart rate decreased nearly significantly after ethanol (P less than 0.06), a tendency that was also ablated by cyclooxygenase inhibition. Thus the acute cardiocirculatory response to ethanol involves an intact prostaglandin synthase system in lambs. To our knowledge, these data are the first documentation that cyclooxygenase enzyme blockade can eliminate the acute cardiac and vascular effects of ethanol in a whole-animal system.

Malignant rhabdoid tumour of the bladder with immunohistochemical and ultrastructural evidence suggesting histiocytic origin

A malignant rhabdoid tumour of the bladder is reported from a girl aged 6. Detailed immunohistochemical and ultrastructural investigations provide evidence which suggests a histiocytic origin for this controversial neoplasm.

Granulocytic sarcoma: misleading immunohistological staining with MT1 and S100 protein antibodies

Tissue from two patients with granulocytic sarcomas stained positively for MT1 and S100 protein antibodies; both of these cases presented considerable clinical and histological diagnostic difficulties until acute myeloblastic leukaemia spread to the bone marrow. Tissues from a further eight patients with granulocytic sarcoma were also examined retrospectively. Seven of them stained for MT1 and four for S100 protein but the traditional histological markers for myeloid cells--chloroacetate esterase and lysosyme--often stained only weakly and focally. This pattern of staining should raise the possibility of a granulocytic sarcoma in otherwise problematic cases.

Results of a prospective study evaluating the effects of mantle irradiation on pulmonary function

Thirty patients with Stages I-III Hodgkin's disease receiving mantle irradiation were prospectively evaluated prior to therapy with spirometry, lung volumes, and tests of diffusing capacity (DLCO). Follow-up examinations were performed at 3, 6, and 12 months and then yearly. Sixteen patients had Hodgkin's disease involving the mediastinum at presentation, 10 were smokers, and 16 received either preirradiation or postirradiation chemotherapy. Mantle doses ranged between 2300 cGy and 4000 cGy (mode of 3750 cGy) given at 150 cGy to 170 cGy tumor dose per day with split-course technique. Pulmonary function test results were translated to percent change from predicted values obtained from normal standards for each age, sex, race, and height. These percent changes were then analyzed as a linear function of time. Twenty patients have been tested greater than or equal to 4 years after treatment with a median time from treatment to last pulmonary function test of 8 years. Changes over time in spirometry included an early, mild decrease in both forced vital capacity (FVC) and forced expiratory volume at 1 second (FEV1), which returned to baseline by 2 years and then gradually decreased to a 10-15% deficit as compared with predicted values at 6-10 years. Additionally, there was a very slight decrease in FEV1/FVC beginning at 1 year and gradually increasing to an 8% deficit at 6-10 years. Changes over time in lung volumes included a mild nadir of total lung capacity (TLC) and functional residual capacity (FRC) at 6 months to a year, which returned to baseline at 2-4 years and then gradually dropped to a 5-10% deficit at 6-10 years. Mean DLCO for the study group was 20% below predicted values prior to treatment and dropped to a low of 30% below predicted at 6 months following treatment, then gradually returned to baseline by 4 years and showed continued improvement to an overall deficit of approximately 10% at 6-10 years. With the exception of FEV1/FVC, the changes noted in spirometry and lung volumes were of insufficient degree to be classified as abnormal. The decrease in FEV1/FVC is indicative of a significant and progressive obstructive ventilatory defect. The effects on pulmonary function tests of smoking, the presence of mediastinal involvement by Hodgkin's disease, and exposure to chemotherapy were assessed by statistical analysis. No subsets of patients demonstrated consistent evidence of a restrictive ventilatory defect expected after irradiation.(ABSTRACT TRUNCATED AT 400 WORDS)

Predictive value of Apgar scores for developmental outcome in premature infants

For more than two decades, Apgar scores have been used to predict developmental outcome in newborns. However, most studies have used full-term babies for their data base, and the predictive value of Apgar scores for low birthweight infants has remained unclear. This study was designed to provide a data base for premature infants, demonstrating to what degree Apgar scores predict developmental outcome. We tested Apgar scores alone and in combination with two other easily quantified variables, birthweight and gestational age, as predictors of risk for 256 infants weighing less than 1800 gm at birth. Although significant correlations existed between Apgar scores and Bayley Mental and Psychomotor Developmental Indices, multiple regression analyses demonstrated that these relationships were not significant independent of birthweight and gestational age. That is, after controlling for birthweight and gestational age, Apgar scores did not predict morbidity in low birthweight infants and should not be used to provide a developmental prognosis.

Clinical and pathological study of dysphagia conservatively managed in patients with advanced malignant disease

A series of patients with dysphagia associated with terminal malignant disease is presented. 33 patients had clinical evidence of organic dysphagia associated with tumours of the upper aerodigestive tract. Over 80% of this group who underwent necropsy had locally obstructive lesions. Conservative treatment alone led to amelioration of dysphagia in approximately 60% of patients.

Carcinogenicity of chemicals: the weight of evidence

1. The evidence discussed here is derived from epidemiology, long-term bioassays in laboratory animals, and predictive short-term tests. 2. Epidemiological data are obtained directly from human studies and are most compelling when they demonstrate a large relative risk and a clear dose-response in association with a distinctive tumour type. Exposure to a suspected carcinogen and the doses involved are, however, often difficult to determine, and the most sophisticated epidemiological methods are relatively insensitive. There are no epidemiological data for most occupational/environmental chemicals. 3. Long-term bioassays can present major problems in design, interpretation and extrapolation. Particular difficulties are associated with the planning of appropriate dose levels and the occurrence of certain tumours at high incidence in both control and test groups. Results from animal bioassays set priorities for concern and action but they cannot be reliably used for quantitative assessment of human risk. 4. Evidence of potential carcinogenicity derived from short-term predictive tests, involving a wide variety of systems with diverse end-points, is increasingly important. Emphasis is placed on the need for more in vivo procedures with a broadening of the scope of somatic cell targets.