Translocation (1;22)(p36;q11.2) with concurrent del(22)(q11.2) resulted in homozygous deletion of <Emphasis Type="Italic">SNF5/INI1</Emphasis> in a newly established cell line derived from extrarenal rhabdoid tumor

Malignant rhabdoid tumor (MRT) is a highly malignant pediatric cancer, which arises in various sites such as the kidney, brain, and soft tissues. Cytogenetic studies have revealed alterations of 22q11 in MRT. Recently, deletions and mutations of the SNF5/INI1 locus in 22q11.2 have been reported in MRT, suggesting that SNF5/INI1 is a tumor suppressor gene for MRT. Here we report our molecular cytogenetic study for a newly established cell line from extrarenal MRT with t(1;22)(p36;q11.2). Consequently, the reciprocal translocation was associated with the interstitial deletion of a small segment including SNF5/INI1, and another, chromosome 22, showed terminal deletion, the breakpoint of which was located 70–80 kb centromeric to SNF5/INI1, resulting in homozygous deletion of SNF5/INI1 in this cell line.     

H-Y antigen expression in patients with X-autosomal translocations and gonadal dysgenesis

Cells from three patients with early gonadal failure and a balanced reciprocal translocation involving the long arm of the X chromosome and an autosome were studied. Fibroblasts from a patient with a similar balanced reciprocal translocation but normal reproductive capabilities were also studied. Two of the four patients were found to have serologically detectable H-Y antigen on their cells. Since H-Y antigen has been found on the cells of other patients with X chromosome abnormalities but without a Y chromosome, it is thought that the X chromosome plays a role in the regulation of H-Y antigen expression. This study suggests that the long arm of the X chromosome may be involved but the location of a regulatory gene cannot be identified in these studies. These cases do not permit us to implicate H-Y antigen as a cause of gonadal dysgenesis and early gonadal failure in females who have structurally abnormal X chromosomes.     

Die urämische Neuropathie in Abhängigkeit von Dialysedauer und -Gerät

Zusammenfassung Eine Umfrage, die sich auf 55 Dialysezentren mit insgesamt 901 Patienten (90% aller in der BRD behandelten Patienten in einem chron. intermittierenden Dialyseprogramm) erstreckte, ergab, daß 7,6% der Kranken an einer klinisch manifesten Neuropathie leiden. Bei 127 von 307 untersuchten Patienten war die motorische Nervenleitgeschwindigkeit an den Beinen herabgesetzt.Die Aufgliederung der Patienten nach der wöchentlichen Dialysedauer und nach verschiedenen Dialysatortypen ergab eine statistisch signifikante Abnahme der Neuropathiehäufigkeit mit zunehmender Dialysedauer—sowohl bei den Spulen—wie auch bei den Plattengeräten. Bei klinisch manifester Neuropathie ließen sich die Symptome in der Regel durch eine Verlängerung der wöchentlichen Dialysedauer um 6 Std bessern.Fehlten Symptome seitens des peripheren Nervensystems, so ließ sich bei einer wöchentlichen Dialysedauer von 26 Std oder mehr, das Auftreten einer klinisch manifesten Neuropathie praktisch völlig verhüten.     

Adjustment of metabolism,catecholamines and β-adrenoceptors to 90 min of cycle ergometry

Adrenaline infusion of 0.1 g · kg^–1 · min^–1 in healthy volunteers results in an increase of hepatic glucose production, an increase of the absolute number of occupied -adrenoceptors and specific changes in metabolism. To compare these effects with the changes induced by an endogenous catecholamine release, we investigated healthy volunteers during cycle ergometry. After fasting at least 14 h seven healthy subjects exercised for 90 min at an intensity of 20% below their individual anaerobic threshold. The rate of glucose production as well as the turnover rates of alanine and leucine were calculated using stable isotope tracers. High and low affinity -adrenergic binding sites on lymphocytes were determined by an equilibrium binding assay with (–)¹²⁵ Iodocyanopindolol. After 90 min of cycling the rate of appearance of glucose increased significantly from means of 2.0 (SD 0.2) to 2.65 (SD 0.50) mg · kg^–1 · min^–1 with unchanged blood concentrations of glucose and lactate. The flux of the amino acids alanine and leucine decreased significantly from means of 0.91 (SD 0.21) to 0.62 (SD 0.14) mg · kg^–1 · min^–1 and from 0.40 (SD 0.05) to 0.32(SD 0.04) mg · kg^–1 · min^–1, respectively. The mean free fatty acid concentration increased significantly from 0.65 (SD 0.33) to 1.27 (SD 0.45) mmol · l^–1 during the endurance trial. The increase of glucose turnover and the decrease of amino acid flux point to a metabolic shift towards enhanced utilization of free fatty acids. Adrenaline and noradrenaline concentrations showed a moderate but significant increase from means of 0.61 (SD 0.20) to 0.99 (SD 0.36) nmol · l^–1 and from 2.27 (SD 0.75) to 3.46 (SD 0.38) nmol · 1^–1, respectively. The number of high affinity -adrenergic binding sites per cell (-adrenoceptors) nearly doubled from 770 (SD 130) to 1490 (SD 150) during 90 min of cycling. The observed endogenous plasma catecholamine concentrations were not sufficient to change significantly the relative receptor occupancy. This would seem to indicate that the aerobic exercise induced effects depended more on the absolute number of occupied -adrenoceptors than on their relative receptor occupancy. When compared to the results of the adrenaline infusion experiment the increases of the hepatic glucose production and the increase of -adrenoceptors were very similar in both groups despite ten times higher adrenaline plasma concentrations in the infusion group. This would seem to indicate that -adrenoceptors mediated effects do not correlate with catecholamine plasma concentrations.     

Localisation of CEA, β-HCG,SP1, and keratin in the tissue of lung carcinomas

Summary One hundred and twenty seven cases of lung tumors were studied by the immunoperoxidase technique for the presence of CEA and-HCG. Twenty-nine of these tumors were additionally stained for keratin and SP1. CEA and SP1 could be demonstrated in 80% of the studied cases, while-HCG was found in only 9%. SP1 revealed an almost identical staining pattern to CEA and keratin was found only in squamous cell carcinomas. The tissue positivity of none of these three markers correlated with tumor size, lymphnodal involvement or histological type.This study was supported by Deutsche Stiftung für Krebsforschung - Dr. Mildred Scheel-Stiftung     

Effect of injury to the zone of the medial forebrain bundle and preoptic region on activity of an epileptiform focus induced by penicillin (on the phenomenon of the hyperactive determinant dispatch station)

Experiments on cats showed that injury to the medial forebrain bundle (MFB) and also partly to the preoptic region on the side of application of penicillin to the cerebral cortex (middle suprasylvian gyrus) causes depression of paroxysmal activity (spike potentials) in the penicillin focus, and also in a secondary mirror focus arising in the symmetrical zone of the opposite cortex. Injury to MFB on the side of the mirror focus causes depression of paroxysmal spike potentials only in that focus and does not affect activity in the primary epileptiform focus. The effects described are examined from the standpoint of views regarding the role of the determinant dispatch station (DDS) in the activity of the CNS: A primary epileptiform focus is a hyperactive DDS which induces the appearance of secondary foci, supports them, and determines the character of their activity. The results of the investigation suggests a role for MFB in the modulation of cortical epileptiform activity.Laboratory of General Pathology of the Nervous System, Institute of General Pathology and Pathophysiology, Academy of Medical Sciences of the USSR, Moscow. Laboratory of Electrophysiology, V. F. Filatov Odessa Research Institute for Eye Diseases and Tissue Therapy, Ministry of Health of the Ukrainian SSR. Translated from Byulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 82, No. 12, pp. 1413–1416, December, 1976.     

Brief Communication: Role of Nuclear Background and in vivo Environment in Variable Segregation Behavior of the Aging-Dependent T414G Mutation at Critical Control Site for Human Fibroblast mtDNA Replication

Previous work had shown a large accumulation (up to 50% of mtDNA) of a noninherited T414G transversion at a critical control site for mtDNA replication in skin fibroblasts from the majority of human subjects above 65 years old, and its absence in younger individuals. In the present studies, long-term in vitro culture of several fibroblasts populations carrying the heteroplasmic T414G mutation revealed an outgrowth of the mutant cells by wild-type cells. This observation supported the previous conclusion that the mutation accumulation is an in vivo phenomenon, while, at the same time, indicating intrinsic physiological differences between mutant and wild-type cells. Furthermore, subcloning experiments revealed a striking mosaic distribution of the mutation in the original fibroblasts populations, as shown by its presence, in heteroplasmic or homoplasmic form, in a fraction (18–32%) of the fibroblasts, and its absence in the others. In other investigations, transfer of mitochondria from mutation-carrying fibroblasts into mtDNA-less 143B.TK^–0 206 cells revealed the persistence of the mosaic distribution of the mutation, however, with a near-complete shift to homoplasmy. The generality of the latter phenomenon would exclude a founder effect by one or few mitochondria in the transformation experiments, and would rather point to the important role of the nuclear background in the in vitro behavior of the T414G mutation. The stability of the homoplasmic mutation in ⁰ cell transformants provides a powerful tool for analyzing its biochemical effects.     

Study on the mechanism of the appearance of noise effects

Summary This study was undertaken to investigate the dose-response relationship between the biological effect and noise exposure, and to consider the mechanism of the appearance of noise effects. Rats were exposed to noise at intensities of 60 dB (A), 80 dB (A) and 100 dB (A) for 240 min and examined for the change of activities of dopamine--hydroxylase (DBH) in serum and adrenal glands. Plasma cyclic adenosine 3,5-monophosphate (c-AMP) levels were also measured. Some rats were given 6-hydroxydopamine (6-OHDA) as a chemical sympathectomyzing agent 20 h before noise exposure in order to consider the mechanism of the appearance of noise effects. By noise exposure, serum DBH activity was significantly (P<0.01) increased at each intensity compared with the control group, but there were no remarkable changes in adrenal DBH activity. Plasma c-AMP level was also significantly elevated in response to the noise stress. When the rats, which had been pretreated with 6-OHDA, were exposed to noise with an intensity of 100 dB (A), the response of serum DBH activity was no longer observed. Therefore it is suggested that the effect due to noise exposure appears through the post-ganglionic sympathetic nerve fiber.     

Astrocytes and intracerebral immune responses

The astrocyte is the most abundant cell within the central nervous system (CNS). This cell subserves a multiplicity of important functions that contribute to the process of neural development as well as to the integrity of normal brain function. Adding to the already exhaustive list of capabilities, the astrocyte has now been demonstrated to function as an intracerebral antigen presenting cell. These findings are serving to revise our view of the brain as an immunoprivileged site and perhaps will shed some light on the pathogenetic mechanisms involved in a number of CNS disorders of immune dysregulation. In this review we provide some perspective on the regulatory mechanisms that influence astrocyte immune functions. Specifically, we address the role played by the major histocompatibility complex (MHC) antigens as well as adhesion molecules in the initiation of brain immune responses.     

PMX2B,a new candidate gene for Hirschsprung's disease

Hirschsprung's (HSCR) disease is a congenital intestinal malformation of the enteric nervous system. It is a multigenic malformation and until now, eight genes have been involved in the etiology of this disease: genes encoding proteins of the RET signaling pathway (RET, GDNF and NTN), genes participating in the endothelin (EDN) type B receptor pathway (EDNRB, EDN3 and ECE-1), the SOX10 gene and the SIP1 gene that is mutated in syndromic forms of HSCR. Mutations of these genes are found in not more than 50-60% of affected individuals. Here, we report on the results of a molecular cytogenetic study performed in a girl who presented with a syndromic short segment HSCR associated with a de novo t(4;8)(p13;p22) translocation. A comparative genomic hybridization (CGH) study found a 4p12p13 deletion. A molecular characterization of this rearrangement showed that the 4p13 deletion was 5 Mb in length and included the paired mesoderm homeobox gene (PMX2B) (MIM 603851), a gene expressed in the human embryonic gut and essential for the development of autonomic neural crest derivatives. The present observation suggests that PMX2B haploinsuffciency might predispose to HSCR.