Renewal of Oligodendrocyte Lineage Reverses Dysmyelination and CNS Neurodegeneration Through Corrected N-acetylaspartate Metabolism

Myelinating oligodendrocytes are essential for neuronal communication and homeostasis of the central nervous system (CNS). One of the most abundant molecules in the mammalian CNS is N-acetylaspartate (NAA), which is catabolized into L-aspartate and acetate by the enzyme aspartoacylase (ASPA) in oligodendrocytes. The resulting acetate moiety is thought to contribute to myelin lipid synthesis. In addition, affected NAA metabolism has been implicated in several neurological disorders, including leukodystrophies and demyelinating diseases such as multiple sclerosis. Genetic disruption of ASPA function causes Canavan disease, which is hallmarked by increased NAA levels, myelin and neuronal loss, large vacuole formation in the CNS, and early death in childhood. Although NAA's direct role in the CNS is inconclusive, in peripheral adipose tissue, NAA-derived acetate has been found to modify histones, a mechanism known to be involved in epigenetic regulation of cell differentiation. We hypothesize that a lack of cellular differentiation in the brain contributes to the disruption of myelination and neurodegeneration in diseases with altered NAA metabolism, such as Canavan disease. Our study demonstrates that loss of functional Aspa in mice disrupts myelination and shifts the transcriptional expression of neuronal and oligodendrocyte markers towards less differentiated stages in a spatiotemporal manner. Upon re-expression of ASPA, these myelination and neuronal lineage markers are either improved or normalized, suggesting that NAA breakdown by Aspa plays an essential role in the maturation of neurons and oligodendrocytes. Also, this effect of ASPA re-expression is blunted in old mice, potentially due to limited ability of neuronal, rather than oligodendrocyte, recovery.

Schwefelkohlenstoff in flüssiger Phase: Assoziation

Das Verhalten des CS2 in flüssiger Phase wird deutlich durch Konfrontation der binären Gemische des CS2 mit anderen binären Systemen. Der Vergleich spektroskopischer und kalorischer Daten ergibt die Existenz einer Eigenassoziation des CS2, für welche sich auch ein Energiebetrag nachweisen läßt. Gemäß einer Schätzung ist als Mindestwert der Assoziations-Energie 1,7 kcal/Mol anzunehmen. Bei der Schätzung werden die Potentiale der Dispersionskräfte auf Grund der Formel von J. Kirkwood berechnet. Bei dieser Gelegenheit kann gezeigt werden, daß die Kirkwood sche Formel plausible und zumindest in der Größenordnung richtige Energiewerte für die Wechselwirkung (Dispersionseffekt) einfacher Molekeln in flüssiger Phase liefert. - Gewisse, durch andere Autoren beschriebene Befunde (Ultraschallabsorption, Verhalten der Wärmekapazitäten, Schwingungsspektren) lassen sich durch Eigenassoziation des CS2, deuten.

Remote infrared chemical sensing using highly durable AlF(3)-based glass fibers

Unclad, low-loss AlF(3)-based glass fibers with enhanced chemical durability have been successfully used for the first time to our knowledge as intrinsic evanescent infrared sensors for monitoring liquid chemicals. Different liquids with absorption bands between 1 and 4.5 microm, such as alcohol, acetonitrile, and mixtures of alcohol/acetonitrile and water/acetonitrile, have been tested. These fibers have also been used successfully as distributed sensors for simultaneous monitoring of different chemical species.

[Measuring subcutaneous fatty tissue as a sonographic parameter for detection of fetal growth retardation and fetal hypertrophy in pregnancy]

This investigation contains a statistical evaluation of sonographic results concerning fetal subcutaneous adipose tissue aiming to examine and assess the relevance of this new sonographic parameter for the detection of fetal growth retardation, resp. fetal hypertrophy during pregnancy. The diagrammatic presentation of the growth of the subcutaneous adipose tissue of eutrophic fetuses shows low validity for the differentiation of hyper- and hypotrophic fetuses. To enable the differentiation between "asymmetric" and "symmetric" types of retardation, the different degrees of growth of the subcutaneous adipose tissue of hypertrophic fetuses have to be taken into consideration. The relation between birthweight and growth of the subcutaneous adipose tissue shows no distinct differentiation of the birthweight, however, presents overlapping categories of the birthweight for diagnostic orientation.

Abnormal pregnancy sonogram and chromosomal anomalies: four years' experience with rapid karyotyping

Over a four-year period, 140 pregnancies with different malformations detected by ultrasound were examined cytogenetically. Gestational age ranged from 13 to 36 weeks. Twenty-six fetuses (18.6 per cent) had abnormal karyotypes, including trisomies, triploidy, monosomy X, and structural anomalies. Similar malformations were found in fetuses with different chromosomal anomalies, indicating that the types of malformations are not specific for particular chromosomal anomalies. Chromosomal analysis was performed on amniotic fluid culture and by direct karyotyping of placental biopsies. Direct karyotyping is suggested to be the most rapid approach, especially if sonographic anomalies are detected close to the 24th week of gestation, shortly before delivery, and in cases of significant oligohydramnios.

Sonographic detection of an asymptomatic rupture of the uterus due to necrosis during the third trimester

This is a report on the first sonographic detection of a silent rupture of the uterus in the 33rd week of pregnancy of a 35-year-old patient. On the basis of the clear sonographic picture immediate cesarean section was (considered) indicated in spite of lack of clinical symptoms. The intraoperative situs confirmed the sonographic diagnosis of a ruptured uterus related to an old cesarean section, combined with partial necrosis of the lower uterine segment.

Partial deletion of 4p in fetal cells not present in chorionic villi

A case of a prenatal diagnosis at the second trimester is presented showing a normal karyotype in 12 metaphases from chorionic villi. In all cultured amniotic cells, however, and also in all fetal fibroblasts analyzed after abortion a structural anomaly (46,XY;del 4(pter----p15.2) was detected. Prenatal diagnosis was performed because of intrauterine growth retardation, cleft lip and esophagus atresia by ultrasound. The fetal stigmata are compatible with the Wolf Hirschhorn syndrome. We conclude that amniocentesis may be indicated notwithstanding a normal CV-diagnosis in those rare pregnancies with a characteristically abnormal ultrasound.

Phagocytic activities in neonatal monocytes

Monocytes play an essential role in cellular host defense as circulating phagocytes, as well as precursors of macrophages. We investigated the principal phagocytic activities in monocytes from cord blood of term infants by analysing adherence, random migration, chemotaxis, bactericidal activity, phagocytosis-associated chemiluminescence, production of superoxide anion (O-2) and generation of hydrogen peroxide (H2O2). All phagocytic functions of monocytes from neonates were shown quantitatively to be comparable to those of cells from healthy adult volunteers. The increased susceptibility of the human neonate to serious systemic infections cannot be related to an abnormality in monocyte function.

[Early detection and incidence of iron deficiency in pregnancy]

For early detection of iron deficiency during pregnancy ferritin, transferrin, serum iron, transferrin saturation and red blood cell (RBC) parameters were measured in 156 pregnant women. The geometric mean of ferritin-concentration was 11.7 +/- 2.7 ng/ml (mean +/- 1 s) which is about 46 ng/ml lower than that in non pregnant women. The duration of pregnancy, the number of pregnancies and the interval from the preceding pregnancy were all considered: 67% had iron deficiency, 18% prelatent, 27% latent and 22% manifest. On the basis of RBC analysis only 30% could be detected correctly. Ferritin detected 90% whereas serum iron, transferrin, transferrin saturation only detected 45% of the cases. The serum ferritin level did not correlate with the number of previous pregnancies but it did correlate with the interval to the last pregnancy. Serum ferritin declined sharply until the 28th week of pregnancy but only slightly thereafter. These data suggest at least one determination of serum ferritin concentration in pregnant women for a sufficient prophylaxis of iron deficiency during pregnancy. The latest time for the measurement should be between the 20th and 23rd week. An additional determination of serum ferritin during the early pregnancy is indicated if the time interval to the preceding pregnancy is shorter than three years.

[Cervix ripening and labor induction in therapeutic abortion in the middle and late 2d trimester using intracervical and extra-amniotic prostaglandin gel administration]

In 64 patients for therapeutic abortion between the 17th to 26th week of pregnancy abortion was induced with a standardized two-step procedure. After priming of the cervix with intracervical application of prostaglandin gel, labour was induced with extraamniotic PG-administration under epidural anaesthesia. The priming effect was demonstrated objectively in 10 patients with a mechanical tonometer. Prostaglandin F2 alpha, PGE2 and sulprostone were used in the study. There were no significant differences in the total length of therapy (cervix priming time plus induction of labour to abortion interval) between the three groups of patients. Except for 4 patients who required an instrumental extraction of the fetus, abortion occurred in all the patients within a total time of 30 hours (93.8%). The mean induction of labour to abortion interval was 8.3 hours (range: 1.0 to 17.3 hours) in all patients and there was, again, no significant difference between the three groups. Epidural anaesthesia gave a painless induction of abortion in 60 out of 62 patients, while 2 patients required additional analgesics. In 2 patients epidural anaesthesia was contraindicated. In contrast to the systemic administration of PG the incidence of gastrointestinal side effects was low (10.9%). In one case a cervical lesion was observed due to a tenaculum laceration. Although there was no general antibiotic prophylaxis endometritis occurred in only 3 cases (4.7%). The combination of intracervical PG gel for cervical priming, extraamniotic PG gel for labour induction and epidural anaesthesia presents a gentle and efficient method for the termination of pregnancy in the middle to late second trimester.

[Relation between procoagulant activity and fetal lung maturity in amniotic fluid]

A total of 146 samples of amniotic fluid from the 15th to 43rd weeks of pregnancy were taken by either transabdominal amniocentesis or amniotomy during birth. In addition to the palmitic/stearic ratio (P/S) the following coagulation tests were determined: clotting time, modified prothrombin time, partial thromboplastin time (PTT), recalcification time and, in selected samples, thrombelastograms. In the course of pregnancy there is a significant shortening of all coagulation tests measured in amniotic fluid. Comparing the values obtained in the 15th to 18th and the 37th to 43rd weeks of gestation and literature results the following values may indicate fetal maturity: clotting time less than 100 sec., modified prothrombin time less than 80 sec., PTT less than 30 sec. and recalcification time less than 80 sec. The lower limit for P/S ratio in normal pregnancy is 5,0. In 58 cases, amniotic fluid was obtained in the 37th to 43rd week at most 24 hours before delivery; there was no case of RDS in this group. Eliminating intermediate P/S values of 4,5 to 5,0 a false negative rate of 1,7% for the prediction of fetal lung maturity was seen. The corresponding rate for the modified prothrombin time was 3,4% and for the clotting time 6,4%. In 7 RDS cases all cases could be properly predicted from the recalcification time and the PTT. The fetal lung maturity may be estimated by means of simple and rapid coagulation tests and this may facilitate the indication for RDS-prophylaxis. The determination of the L/S or P/S ratios, however, cannot yet be dispensed with.

[Diagnosis of fetal sex from trophoblast DNA]

By using recombinant DNA technology fetal sex determination was performed with 13 different trophoblast samples. In all cases trophoblast and fetal sex were identical. The importance of first trimester trophoblast biopsy for the prenatal diagnosis of inherited disease is being discussed.

Changes of the clinical presentation of abruptio placentae

There is an increase of the diagnosis "a.p." during the last years, especially stage 0 + 1. Qualified US monitoring seems to be responsible for this fact. Abruptio placentae is reversible in some cases. Conservative management can be done under intensive care conditions if antenatal treatment is indicated.

Exencephaly in Cantrell-Haller-Ravitsch Syndrome

A case of exencephaly associated with spinal dysraphism and Cantrell-Haller-Ravitsch syndrome is described. Significant findings included exencephaly, multiple subcortical neuroepithelial islets with active proliferation, cerebellar aplasia, and abnormal flexion of the neuraxis with spinal dysraphism of the cervicothoracic region. The various features of exencephaly, anencephaly, and iniencephaly are discussed. The significance of subcortical growth zones is evaluated in the light of experimental observation.s

Urinary excretion, osmolarity and electrolytes after bolus-injection of fenoterol in female rabbits

The effects of bolus injections of 1.0-80.0 micrograms/kg body weight fenoterol on urinary excretion, osmolarity and electrolytes were studied in unanesthetized, water-loaded rabbits. In animals infused initially with isotonic solution over 2 h with 60 ml/h and thereafter over 10 h with 45 ml/h, urine excretion was 538 ml/12 h, sodium excretion was 65.4 mmol/12 h, and potassium excretion was 4.8 mmol/12 h. In animals injected with 5.0-80.0 micrograms/kg body weight fenoterol, a strong antidiuresis occurred, lasting for 2 (10.0 micrograms/kg) to 4 h (80.0 micrograms/kg). Due to the strong antidiuresis, urinary osmolarity was significantly elevated for 2 (10.0 micrograms/kg) to 3 h (80.0 micrograms/kg). The changes of sodium excretion after fenoterol injection were very similar to those of urine excretion. Maximum reduction of sodium excretion was found after injection of 10.0-80.0 micrograms/kg body weight fenoterol, the effect lasting for 1 h (10.0 micrograms/kg) to 4 h (80.0 micrograms/kg). Potassium excretion was significantly reduced after injection of 5.0-80.0 micrograms/kg body weight fenoterol. In contrast to all the other parameters measured, potassium excretion remained significantly reduced until the end of the infusion period in animals treated with 10.0-80.0 micrograms/kg body weight fenoterol and was not dose dependent. Our data presented in this work extend earlier findings in the rabbit in that bolus injection of fenoterol also results in a drastic decrease of urine and electrolyte excretion. The results are discussed with special reference for the management of acute fetal distress with betamimetics and to the development of pulmonary edema that has been shown to occur under therapy with betamimetics on both female rabbits and humans.

Congenital ventricular diverticulum in the brainstem. Report of four cases

This report concerns rare ventricular malformations observed in four fetal brains. Multiple aqueductal diverticula were the only malformation of the central nervous system (CNS) in one case, unilateral diverticula of the 4th ventricle in a holoprosencephaly and a hydrocephaly, and a ventral accessory aqueduct in a fetus with trisomy 18. These findings are the pathologic progression of embryonal ventricular recesses which may be seen in normal brains.

[Early stage of a cloverleaf skull malformation]

Cloverleaf skull anomaly was diagnosed sonographically and in the fetogram, together with concomitant chondrodystrophy. This resulted in an indication for intentional abortion in the 29th week. Consequently, this rare form of skull monstrosity could be examined pathologico-anatomically for the first time in a very early stage of foetal development. Contrary to the widely held opinion that the reason for such hideous malformation is a hydrocephalus internus due to a deformation of the skull base, we found a practically negligible hydrocephalus, although the cloverleaf skull had already developed in a very marked manner. Hence, this case contradicts the generally adopted formal pathogenetic interpretation of cloverleaf skull monstrosity.

Transient congenital hypothyroidism after amniofetography

A newborn infant who presented with giotrous congenital hypothyroidism is described. Thyroid dysfunction was due to amniofetography performed 4 days before delivery, during which a total of 5.22 g of iodine as water- and lipid-soluble contrast medium was injected. After oral L-thyroxine treatment hypothyroidism disappeared rapidly. Thyroid function remained normal when treatment was withdrawn after 28 days, underlining the transient character of hypothyroidism.

[Necessity of training and safety in gynecological laparoscopy--a contradiction?]

At the Gynaecological University Hospital Göttingen 1659 laparoscopies were performed 1961-1978 by 67 gynaecologists with an average of 24,8 laparoscopies per gynaecologist. Most of the doctors were still in their training period, assistance was always given by a specialist gynaecologist. Only in 5 cases (0,3 per cent) laparotomy was necessary due to complications following laparoscopy or laparoscopicsterilization. Injuries of the transverse colon, the greater omentum and a mesenteric artery-caused by the trocar-were seen, also diffuse bleeding from the parietal peritoneum and from the ramus of the Fallopian tube. No deaths due to laparoscopic complications occurred. The incidence of severe complications can be kept within tolerable limits in a training hospital where the majority of the operations are performed by doctors in training, when the following conditions are strictly adhered to: Careful consideration of the risks involved in laparoscopy/laparoscopic sterilization and other less invasive diagnostic and contraceptive methods, strict attention to the contraindications of laparoscopy and performance of a standardized laparoscopic technique under the supervision of an experienced operateur.