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}lungerford DA: Chromosome preparations of leukocytes cultured from human peripheral blood. Exp Cell Res 20:613, 1960. 6. Seabright M: A rapid banding technique for human chromosomes. Lancet 2:971, 1971. 7. Van Eys J, Flexner JM: Transient spontaneous remission in a case of untreated congenital leukemia'. Am J Dis Child 118:507, 1969. 8. Ross JD, Moloney WC, Desforges JF: Ineffective regulation of granulopoiesis masquerading as congenital leukemia in a mongoloid child. J PEDIATR 63:1, 1963. 9. Lazarus KII, Iieerema NA, Palmer CG, Baehner RL: Myeloproliferative reaction in a child with Down's syndrome: Cytological and chromosomal evidence for a transient leukemia. Am J ttematol 11:417, 1981. 10. Rowley JD: Down's syndrome and acute leukemia: Increased risk may be due to trisomy 21. Lancet 2:1020, 1981. I1. Lin tl-P, Menaka II, Lim K-tl, Yong ItS: Congenital leukemoid reaction followed by fatal leukemia: A case with Down's syndrome. Am J Dis Child 134:939, 1980. 12. Chu J-Y, Weldon BC: Acute leukemia in a patient with Down's syndrome and transient congenital leukemia. Am J Dis Child 136:367, 1982.

The effects of hydration on the base curve of CAB lenses were measured with a radiuscope. A significant amount of lens warpage and variability in curvature was detected in all lenses under conditions of continuous hydration. Thinner lenses flattened more than thicker lenses of the same power. Lenses of greater minus power flattened more than lenses of less minus power for a given lens thickenss. Plus power lenses were more stable than minus power lenses. Control lenses, stored dry, did not flatten or warp.

This study examined Schwann cell behavior during paranodal demyelination induced by beta,beta'-iminodipropionitrile (IDPN). The stimuli for Schwann cell proliferation, extensively studied in vitro, are less well understood in vivo. Most in vivo systems previously used to examine Schwann cell proliferation in disease are dominated by loss of internodal myelin sheaths. As used in this study, IDPN administration produces neurofilamentous axonal swellings and paranodal demyelination, without segmental demyelination or fiber degeneration. We asked whether Schwann cells would proliferate following the restricted paranodal demyelination that accompanies the axonal swellings, and if so what the sources and distributions of new Schwann cells might be. IDPN was given as a single large dose (2 ml/kg) to 21-d- old rats. Neurofilamentous axonal swellings formed in the proximal regions of motor axons, reaching their greatest enlargement in the root exit zone 8 d after IDPN administration. These swellings subsequently migrated distally down the nerves at rates approaching 1 mm/d. The axonal enlargement was consistently associated with displacement of the myelin sheath attachment sites into internodal regions, and consequent paranodal demyelination. This stage was associated with perikaryal changes, including nucleolar enlargement, “girdling” of the perikaryon, and formation of attenuated stalks separating the perinuclear region from the external cytoplasmic collar. Schwann cells proliferated abundantly during this stage. Daughter Schwann cells migrated within the endoneurial space (outside the nerve fiber basal laminae) to overlie the demyelinated paranodes of swollen nerve fibers. In these regions, local proliferation of Schwann cells continued, resulting in large paranodal clusters of Schwann cells. As the axonal calibers subsequently returned to normal, the outermost myelin lamellae of the original internodes returned to their paranodal attachment sites and the supernumerary Schwann cells disappeared. Formation of short internodes, segmental demyelination, and nerve fiber loss were rare phenomena. These results indicate that paranodal demyelination is a sufficient stimulus to excite abundant Schwann cell proliferation; neither internodal demyelination nor myelin breakdown is a necessary stimulus for mitosis. The 3H-thymidine incorporation studies indicated that the sources of new Schwann cells included markedly increased division of the Schwann cells of unmyelinated fibers and, as they formed, supernumerary Schwann cells. In addition, there were rare examples of 3H-thymidine incorporation by Schwann cells associated with myelinated nerve fibers.(ABSTRACT TRUNCATED AT 400 WORDS)

After repeated exposure, acrylamide (AC) produces degeneration of distal axons. Because neurons whose axons have been injured (e.g. by axotomy) show alterations in their structural and chemical properties, the present study was designed to differentiate the direct effects of AC intoxication from neuronal responses secondary to axonal injury caused by AC. Rats were given AC as either a single high dose (75 mg/kg), or as daily intraperitoneal injections (30 mg/kg, six days per week for four weeks). Dorsal root ganglia of the fifth lumbar level, L5, were examined using a variety of monoclonal antibodies directed against nonphosphorylated (2–135) and phosphorylated (03-44, 06-17, 07-05) epitopes of 145 and 200 kilodalton neurofilament proteins. In control rats, antibody 2–135 stained axons and neuronal cell bodies; antibodies against phosphorylated epitopes of neurofilaments stained only axons distal to the glomerulus. Following chronic AC intoxication, all three antibodies directed against phosphorylated epitopes of neurofilaments (particularly 07–05) demonstrated intense immunoreactivity in 20–300% of neuronal cell bodies. In addition, the glomerular region of these axons was stained. Electron microscopy revealed many chromatolytic cells containing few neurofilaments. In contrast, a single high dose of AC produced no abnormal staining of neuronal cell bodies at a time when slow axonal transport was impaired. Our findings are compared to those observed following axotomy and to those occurring in aluminum-intoxicated rabbits, two experimental disorders in which altered distributions of phosphorylated filaments have been documented.

Neurofilamentous giant axonal swellings are observed in a number of human disorders, although they can manifest at different locations (i.e. proximal or distal) along the axon. Recent advances in understanding the pathogenesis of these changes has resulted from correlations of ultrastructural changes with abnormalities in the axonal transport of neurofilament proteins in experimental models produced by toxic chemicals. Using single, high doses of either acrylamide or 2,5-hexanedione, a reduction in neurofilament transport has been shown in the rat sciatic nerve. In contrast to the distal axonal swellings observed upon repeated exposures to these agents, modest proximal axonal swellings containing increased neurofilament content are found following high dose exposures. Thus, regardless of the location of swelling production, a defect in slow transport appears to underlie swelling formation. beta,beta'-Iminodipropionitrile (IDPN) produces proximal neurofilamentous giant axonal swellings which are indistinguishable from those observed in some patients with amyotrophic lateral sclerosis (ALS). Although not a model for ALS, IDPN provides a means to study the functional consequences of proximal giant axonal swellings. Intracellular recordings from IDPN-intoxicated cats reveal a number of abnormalities which may have electrophysiological counterparts in ALS, suggesting that the swellings may be important in the expression of the disease. Although axonal degeneration is rarely observed in the cat, perikaryal recordings reveal a number of alterations which are strikingly similar to those obtained from chromatolytic motor neurons following nerve transection. A perturbation of "trophic" signals from the periphery may be involved in the generation of axotomy-like changes in IDPN-intoxicated cats.

Pacemaker malfunction caused by mechanical failure at the site of electrode generator connection has been observed in 5 patients fitted with unipolar pacemakers. Intermittent failure to capture occurred in one patient. The fault was the same in each case and resulted from fracture of a plastic screw designed to hold an insulating cap in place over the electrode generator connection. Changes in impulse amplitude, relative pacing threshold, and distortion of the shape of the pacemaker impulse (overshoot of the leading and trailing limbs and prolongation of the plateau length) occurred in each case, and are helpful in making the diagnosis. In contrast no significant change occurred in the frontal plane axis of the pacemaker impulse. It is concluded that current leaks in unipolar pacemakers can be of sufficient magnitude to cause failure to capture. Early detection is important and is best achieved by examination of the pacemaker signal for amplitude and shape, and assessment of pacing threshold where possible.

Unusual electrical interactions between neuronal elements of cat spinal cord were examined during the evolution (7-70 days) of proximal paranodally demyelinated axonal enlargements in alpha motor axons induced by beta, beta'-iminodipropionitrile (IDPN) treatment, 50 mg/kg ip, once weekly for up to 5 weeks. The electrical cross talk was observed as early as 7 days of the neuropathy, at which time it occurred in 17.0% of all motoneuron perikaryal recordings. The incidence was greater at 14 (39.1%) and 35 (26.1%) days, without preferential involvement of any motoneuron type. The frequency of recordings from axonal swellings increased from 7 to 35 days but without an increase in cross talk per recording. At 70 days of the neuropathy, L7 ventral root was stimulated repetitively to examine a possible influence of potassium on cross talk. Subsequently, action potentials could be elicited in motoneurons by stimulation of additional other ventral root filaments. These studies are in agreement with the lack of direct electrical apposition between excitable membranes in IDPN neuropathy but suggest support for a role for an accumulation of extracellular potassium, due to paranodal demyelination as the axon enlarges, in the pathogenesis of these aberrant electrical interactions.

Administered the Child Abuse Potential (CAP) Inventory to 99 parents assessed as "At Risk" of parenting problems by the At Risk Parent-Child Program, Inc., Tulsa, Oklahoma. The study was designed to determine the number and extent of elevated abuse scores in an "At Risk" group compared to a norm group and to discover whether present "At Risk" parents were more seriously "At Risk" than past clients in the same program. During a 3-year period participants were offered the CAP-Inventory as part of the routine evaluation process. Results indicated the "At Risk" group scored significantly above a norm group, with 58% and 52% of the "At Risk" parents scoring above the 95th and 99th percentiles of the norm group, respectively. Comparison of the present results with data from a previous study in the same program (MilnerAyoub, 1980) showed that the present "At Risk" group earned a significantly higher mean abuse score and had significantly more individual scores above the 95th and 99th percentiles of the norm group than did previous "At Risk" parents. The data indicated the Program is currently more effective in the selection of parents in need of its services. However, because the clients are in greater need, other findings (Thomasson, Berkovitz, Minor, Cassle, McCord,Milner, 1981) suggest that the Program may now find itself having a more difficult time demonstrating program effectiveness because participants may be more resistant to treatment.

A new model of neurofilamentous axonal abnormality is described which employs combined administration of beta,beta'-iminodipropionitrile (IDPN) and acrylamide (AC). The model was developed to test the hypothesis that IDPN-induced swelling increases the vulnerability of the distal axon to a second neurotoxic chemical insult. Rats were given a single intraperitoneal (IP) injection of IDPN (1.5 g/kg) one week before receiving a single injection of AC (75 mg/kg, IP). Axonal degeneration was observed at multiple levels along the sciatic nerve at two weeks (with reference to IDPN administration), and was not progressive up to five weeks. Quantitation of degenerating fibers demonstrated that the extent of degeneration increased distally along the sciatic nerve. Single administration of either IDPN or AC did not produce degeneration. Thus, IDPN-induced neurofilamentous swellings alter the susceptibility of the axon to AC neurotoxicity. Two variations of this model were also studied. First, rats given five daily injections of AC (30 mg/kg, IP) beginning one week following IDPN administration developed accumulations of fast axonally transported materials in IDPN-induced microtubule channels. Second, rats given chronic injections of AC (30 mg/kg, IP, five days/week, for four weeks), to reduce the delivery of neurofilaments to the proximal axon, developed less prominent axonal enlargements when challenged with IDPN. Thus, axonal atrophy can mask the development of neurofilamentous axonal swellings.

Motoneurons (MNs) exhibit characteristic electrophysiological alterations following axotomy which are concomitants of perikaryal remodeling induced by the axonal injury. beta,beta'-Iminodipropionitrile (IDPN) neurotoxicity, which produces proximal axonal swellings in the first internodes of motor fibers, was studied as a model of perikaryal electrophysiological properties in axonal pathologies without axonal degeneration. Similarities between parameters of MN excitability (delayed depolarizations, repetitive discharge, and the afterhyperpolarization potential, AHP) known to occur in axotomized MN and those in IDPN neuropathy were examined in type-identified spinal MN of cats during the evolution (7 to 35 days) of proximal axonal swellings. Delayed depolarization potentials were observed frequently in fast MN types throughout the neuropathy but only at 35 days in slow MN types. Similarly, repetitive firing occurred most prominently in fast MNs early in the neuropathy. Concomitantly, AHP duration decreased as early as 7 days in all MN types and was significantly shortened in types FF, FR, and S motoneurons. AHP peak amplitude and current declined continuously from 7 to 35 days of the neuropathy and were significantly (p less than 0.05) decreased at 35 days in types FF and S MNs. These results suggest that not only are fast MN types vulnerable early in IDPN neuropathy, but also that all MN types exhibit electrophysiological changes strikingly similar to those following mechanical axotomy. The possibility is raised that IDPN may initiate electrophysiological changes, analogous to perikaryal remodeling, by mechanism(s) unrelated to axonal degeneration.

We recently encountered a patient in whom placental implantation occurred directly in carcinoma of the endometrium. At the time of surgery for a presumed tubal pregnancy, the 33-year-old patient was discovered to have bilateral ovarian tumors that were histologically identical to the endometrial neoplasm.

β, β′-Iminodipropionitrile (IDPN) was given to cats (50 mg/kg/week for 5 weeks) to induce giant axonal swellings in the proximal internodes of motor axons. Conventional intracellular recording techniques were used to investigate the influence of the axon swellings on axonal impulse conduction and generation of action potentials in unidentified lumbosacral motoneurons (MN). Action potentials recorded from axon swellings, verified by lack of orthodromically or antidromically elicited EPSPs or IPSPs, afterhyperpolarization potentials or initial segment-somaldendritic (IS-SD) inflections, were variable in shape. Some were indistinguishable from recordings in normal axons. Component or extra potentials occurred in 45% of recordings from axon swellings; their position on the action potential depended on the direction of impulse invasion into the swelling. Many action potentials were broad, with amplitudes less than 30 mV. Impulse conduction was estimated to be blocked in 19% of motor axons tested. Action potentials recorded in MN of IDPN treated cats resembled in many aspects those recorded in chromatolytic MN, with increased latencies upon antidromic stimulation and decreased IS conduction times and SD thresholds; other parameters did not differ significantly. The minimal interval between two stimuli which each evoked action potentials increased from3.3 ± 0.1to5.8 ± 0.5ms. IS-SD portions of the action potentials could not be fractionated in 49% of cells regardless of interpulse interval. Many MN failed to follow frequencies as low as 10 Hz. Delayed depolarizations were observed in 14% of MN recordings. Repetitive action potentials were elicited by single stimuli in 14% of MN and more frequently by orthodromic than antidromic stimulation. Action potentials could often be elicited in the same MN by stimulation of more than one ventral root filament. The incidence of this ephaptic transmission or crosstalk was estimated to be 12%. The findings are discussed in terms of the influence of proximal axon swellings on action potential generation in MN, propagation along non-homogeneous regions of axons and functional chromatolysis.

A new technique for assessing implanted cardiac pacemaker function in the ambulant patient has been introduced and assessed. A modified portable electrocardiograph recorder is used to store 24 hours of electrocardiograms along with marker pulses indicating the timing of pacemaker impulses. The recorder detects this narrow impulse and records a wider marker pulse on a second channel. The false positive detection rate was estimated from recordings, each of 24 hours, taken from 10 patients. All of these patients were ambulant and none had a cardiac pacemaker. There was on average less than one false positive per 24 hours. When similar recordings were taken from a group of 15 patients with pacemakers, the average false positive rate in 13 of these patients was also less than on per 24 hours. In the two other recordings artefacts resulted in false positive rates of 28 and 960 per 24 hours. Failure to detect pacemaker pulses was confirmed in only one patient. In addition to determining the accuracy of pacemaker pulse detection, the clinical usefulness of this technique was assessed. Two patients had fixed-rate pacemakers and 13 had demand pacemakers. Of the latter, two patients had a total of three episodes of failure to sense, one patient frequently failed to capture, and six patients had episodes of inappropriate inhibition of the pacemaker, the number of episodes ranging from one to 21 in 24 hours. Paced complexes were easily identified even when they occurred as fusion complexes. The frequency of paced complexes was quantified in each patient and varied from 21 to over 100 000 impulses in the 24 hour period.

beta,beta'-iminodipropionitrile (IDPN) causes giant axon swellings in proximal internodes of spinal motor axons and in stem processes of dorsal root ganglia neurons. The electrophysiological consequences of the swellings were investigated in cats given IDPN (50 mg/kg i.p.) weekly for 0 (control), 1 (7 days), 2 (14 days), or 5 (35 days) weeks; some additional animals were studied 15 (50 days) or 65 (100 days) days following the fifth injection. Extracellular recordings of the spinal monosynaptic reflex revealed amplitudes of efferent responses to be equally reduced at 35, 50 and 100 days. Single stimulation of dorsal roots, or soleus or medial gastrocnemius afferents often evoked doublet efferent responses which arose intraspinally. Similar repetitive responses were observed in dorsal root (afferent) input upon single stimulation of peripheral nerves. Latencies to monosynaptic responses became progressively prolonged over 100 days; spinal cord contribution to the increased latencies was maximal by 35 days. Conduction velocities in single soleus and medial gastrocnemius axons declined to 70 and 64% of normal by 50 days and to 56 and 50% of normal by 100 days respectively. Maximal recurrent inhibition was reduced 42-49% by 35 days and quantitatively similar at 50 and 100 days. Intracellular recordings from spinal motoneurons revealed that, at 35 days, action potentials could be elicited by orthodromic but not by antidromic stimulation in 14% of cells tested. This was taken as evidence of block of impulse conduction by the intervening axonal swelling upon antidromic stimulation. The possibility of abnormal electrical interactions between swollen and demyelinated intraparenchymal axons was tested by determining the number of ventral root fibers via which antidromic stimulation would elicit an action potential in the same motoneuron perikaryon. Electrical crosstalk, never seen in normal animals, varied in incidence during the evolution of the neuropathy (7-35 days), reaching a maximum of 30% at 14 days. Many motoneuron action potentials were remarkably similar to those observed in chromatolytic motoneurons, exhibiting, among other features, decreased SD thresholds and IS conduction times, reduced amplitudes and durations of afterhyperpolarization, delayed depolarizations and an enhanced propensity to fire repetitively upon single stimulation. There was no morphological evidence of chromatolysis in the motoneurons. The concept of "functional axotomy" is introduced to accommodate these findings and discussed in terms of altered dendritic excitability. Not all motoneuron types are equally compromised in the neuropathy.(ABSTRACT TRUNCATED AT 400 WORDS)

Arion et al; (Arion, W. J., Wallin, B. K., Lange A. J., and Ballas, L. M. (1975) Mol. Cell. Biochem. 6, 75-83) propsed a model for glucose-6-phosphatase in which the substrate was transported across the microsomal membrane by a carrier before hydrolysis on the cisternal side. Evidence to support this model has been obtained by studying the inhibition of the enzyme by pyridoxal-P. Pyridoxal-P was a linear noncompetitive inhibitor of glucose-6-phosphatase (EC 3.1.3.9) in freshly isolated ("intact") microsomes from rat liver. Pyridoxol-P was a much less effective inhibitor and no inhibition was observed with pyridoxamine-P. When microsomes were subjected to nitrogen cavitation, treatment with solium deoxycholate, or glutaraldehyde fixation, the Km of glucose-6-phosphatase for glucose-6 P decreased from approximately 6 mM to approximately 2.5 mM; the corresponding change in the Vmax ranged from-10% to +40%. The same procedures decreased the inhibition of glucose-6-phosphatase by pyridoxal-P several-fold. No inhibition by pyridoxal-P was observed in a preparation of glucose-6-phosphatase purified approximately 20 fold (on the basis of Vmax) from micoromes. A nondialyzable inhibitor was apparently formed when intact microsomes were reacted with pyridoxal-P and NaBH4; this inhibition was also reversed by procedures which changed the kinetic properties of glucose-6-phosphatase.

This study examined the relationship between child abuse, as measured by the Child Abuse Potential (CAP) Inventory, and authoritarianism, as measured by the Public Opinion Scale (POS). The study also attempted to provide convergent and discriminant validity for the CAP abuse factors rigidity and loneliness by correlating these factors with the Edwards Personal Preference Schedule (EPPS) variables order and affiliation, respectively. Group One consisted of 150 undergraduate students. Group Two consisted of 34 adult students from a second site. For the subjects in both groups, a nonsignificant relationship (p greater than .05) between abuse scores and authoritarianism was found. In contrast, in both groups significant relationships (p less than .05) were found between the CAP abuse factor rigidity and authoritarianism. Additional analysis indicated a significant inverse relationship (p less than .05) between the EPPS variable affiliation for Group One, but not for Group Two (p greater than .05).

The convergent validity of the Child Abuse Potential Inventory (CAP) was investigated (N = 254). Because the CAP was designed to measure elements of individual pathology and interactional problems related to physical child abuse, it was predicted that CAP scores would be related to a measure of psychological status, the Mental Health Index (MHI). Specifically, it was predicted that the CAP would be correlated positively with MHI measures of psychological distress and, to a lesser degree, correlated inversely with MHI measures of psychological well-being. Because the CAP measures variables predictive of abusive behavior, a substantial relationship was expected between the CAP and the MHI Loss of Behavioral/Emotional Control scale. All hypotheses were supported.

Hereditary canine spinal muscular atrophy (HCSMA), a dominantly inherited disorder of motor neurons, has three phenotypes: accelerated, intermediate, and chronic. In the accelerated and intermediate phenotypes, axonal sizes in ventral roots were smaller than in controls. Reductions in axonal size occurred primarily in large axons, and the frequency of small-caliber axons was increased. In HCSMA, nerve fiber shape, i.e., circularity, was reduced, and the relative thickness of the myelin sheath as a function of axonal caliber was decreased. The density of fibers in motor nerves was increased, making it unlikely that a selective loss of large-caliber axons explained the increased frequency of small-caliber axons. These observations suggest that, in HCSMA, changes in axonal size in motor nerves are associated with both growth arrest and axonal atrophy.

Incidence Acute non-specific pericarditis (acute benign pericarditis; acute idiopathic pericarditis) has been recognized for over 100 years (Christian, 1951). In 1942 Barnes & Burchell described fourteen cases of the condition and since then several series of cases have been published (Krook, 1954; Scherl, 1956; Swan, 1960; Martin, 1966; Logue & Wendkos, 1948). Until recently Swan's (1960) series of fourteen patients was the largest collection of cases in this country. In 1966 Martin was able to collect most of his nineteen cases within 1 year in a 550-bed hospital. The disease is thus by no means rare and warrants greater attention than has previously been aceorded it, despite its usually benign course.