摘要:

Using deletion mapping and complementation tests, we have localized 5 behavioral mutations:shaking-B2, small optic lobesKS58, sluggish-AEE8S, stonedts1, andstress-sensitive-C1to 4 genetic complementation groups at the base of the X-chromosome.Shaking-B2is an allele of the lethal complementation groupR-9-29 near band 19E3;small optic lobesKS3Sandsluggish-AEES5belong to adj acent complementation groups, between lethalsW2andA112near band 19F4; andstoned' andstress-sensitive-Care both alleles of theSP1lethal complementation group between lethals114and13E3near bands 20B-C.

ISSN:0167-7063    

DOI:10.3109/01677068709102329

出版商:Taylor&Francis    

年代:1987

数据来源: Taylor

摘要:

TheaperC (abnormal proboscis extension reflex C)mutation ofDrosophilacauses the degeneration of a particular pair of head muscles involved in the proboscis extension. To define the mechanisms underlying the muscle degeneration, we studied the influence of use or disuse on the muscle degeneration by two kinds of immobilization experiments. In the first experiment, the rostrum was fixed onto the cranium and the extension of the proboscis was mechanically prevented. In the second experiment, we created anaperCaperAdouble mutant, genetically preventing proboscis extension with theaperAmutation. Both immobilizations suppressed the muscle degeneration inaperCmutant flies.

ISSN:0167-7063    

DOI:10.3109/01677068709102330

出版商:Taylor&Francis    

年代:1987

数据来源: Taylor

摘要:

Prospective anterolateral neural fold was grafted from normal axolotls into the posterior neural fold region (statocyst area) ofeyelessmutant hosts. These unilateral anteroposterior grafts stimulated bilateral eye formation in theeyelessmutant at a rate of 79%. Replacing the statocyst area of mutants with the statocyst area from normals stimulated bilateral eye formation in 49% of the cases. Grafting of prospective anterolateral neural fold between normals and mutants or excising the statocyst region of mutants, had no effect. The results are interpreted on the basis of a hypothetical anteroposterior morphogenetic system that might be out of balance in the mutant.

ISSN:0167-7063    

DOI:10.3109/01677068709102331

出版商:Taylor&Francis    

年代:1987

数据来源: Taylor

摘要:

We report on a family segregating the myotonic dystrophy (DM) gene and at(5;8)reciprocal translocation. The DM presented the characteristics typically seen in this disease, i.e. full penetrance, broad expressivity, apparent anticipation in successive generations, presence of a congenital form transmitted by a carrier mother. The family was uninformative for linkage studies with theLutheranandSecretorloci. The concordance between DM and chromosome translocation in 8 out of 9 individuals at risk was apparently due to chance.

ISSN:0167-7063    

DOI:10.3109/01677068709102332

出版商:Taylor&Francis    

年代:1987

数据来源: Taylor

摘要:

Neurological studies were performed in a young boy with keratitis, ichthyosis and deafness syndrome. Skin biopsy showed features of ichthyosis. Clinically and electrophysiologically, he had normal motor and sensory systems, but there was an acoustic nerve lesion and absence of tendon reflexes. Audiometry and brainstem auditory evoked potentials showed bilateral neurosensory deafness. Poor vision may not be due to an optic nerve lesion as evidenced on visual evoked potential findings, but is probably due to pronounced vascularizing keratitis of the cornea. Computer tomography scan showed mild hypoplasia of the inferior vermis and left side of the cerebellum.

ISSN:0167-7063    

DOI:10.3109/01677068709102333

出版商:Taylor&Francis    

年代:1987

数据来源: Taylor

摘要:

The pre-imaginal development ofDrosophilamushroom bodies is under the influence of an unknown variable which causes populations of wild-type flies at eclosion to differ in the average number of Kenyon cell fibers. During the first week of adult life the number adjusts to an intermediate level which depends upon the experience of the flies. Under olfactory deprivation or social isolation it reaches a lower level than under favorable rearing conditions (/.Neurogenet., 1 (1984) 113–126). The biochemical learning mutantsdunceandrutabagashow no experience-dependent modulation of fiber number (Fig. 2). In both strains the mushroom bodies of young adults seem to develop abnormally: induncea loss of about 600 fibers is observed, inrutabagafiber number is low at eclosion and does not increase (Fig. la). The following model for long-term memory is proposed: in mushroom bodies outgrowth and decay of Kenyon cell fibers occur simultaneously. The fibers randomly form transient synapses onto extrinsic output neurons of the mushroom bodies and receive synapses from modulating neurons. Experience consolidates certain synapses, thus prolonging survival of the respective Kenyon cell fibers and increasing the steady state level of fiber number (Fig. 3).

ISSN:0167-7063    

DOI:10.3109/01677068709102334

出版商:Taylor&Francis    

年代:1987

数据来源: Taylor

摘要:

We used the hippocampal slice to examine extracellular electrophysiological responses to nicotine and the difference in sensitivity to nicotine-induced electrophysiological effects between the DBA and C3H mouse strains. Nicotine enhanced CAj population spikes (PS) evoked by Schaffer collateral stimulation in a concentration-dependent manner (100μM to 3.2 mM). This enhancement was slow to appear, achieving a maximum after 15 min. The enhanced PS was accompanied by the development of epileptiform activity (multiple PS's) at nicotine concentrations≥400μM. Slices from DBA mice were significantly more sensitive than those from the C3H strain to these electrophysiological effects of nicotine. Mecamylamine (400μM) blocked both the nicotine-induced PS enhancement and secondary population spikes in both strains, suggesting the involvement of nicotinic cholinergic receptors.

ISSN:0167-7063    

DOI:10.3109/01677068709102335

出版商:Taylor&Francis    

年代:1987

数据来源: Taylor

摘要:

An infant with propionic acidemia presented at one month of age with hyperammonemic coma. Treatment by two double-volume exchange transfusions did not have an appreciable effect, but hemodialysis led to a substantial reduction of the serum concentration of ammonia on two occasions. Nevertheless, continued therapy with sodium benzoate, arginine-HCl, carnitine and lactulose did not have any observable effect on the blood concentration of ammonia. Treatment with sodium phenylacetate was followed by a reduction in serum concentrations of ammonia to normal levels which were maintained. These observations demonstrate the dramatic reduction in serum concentrations of ammonia that may be obtained in patients with organic acidemia by hemodialysis. They suggest that pharmacologic acylation therapy with phenylacetate may be of lasting benefit in the management of this complication.

ISSN:0167-7063    

DOI:10.3109/01677068709102336

出版商:Taylor&Francis    

年代:1987

数据来源: Taylor

摘要:

In order to identify the genetic locus responsible for familial dementia of the Alzheimer type (DAT), we are studying 10 families in which DAT appears to be inherited as an autosomal dominant trait. Genotypes for a TaqI restriction fragment length polymorphism (RFLP) at the apolipoprotein CII locus were determined for the following groups: affected and unaffected DAT family members, DAT subjects with no family history of the disease, and normal control subjects. The control group included 103 individuals from our study and 123 from the study of Wallis et al.(Hum. Genet., 68 (1984) 286). The frequency of the TaqI fast (F) allele in the affected familial DAT subjects (0.64±0.08) differed significantly from that for the control group (0.39±0.02) (Z = 2.87,P0.40). Subsequently, genotypes were determined for two other polymorphisms at the Apo CII locus: a BanI RFLP and a Bgll RFLP. For these two polymorphisms, the allele frequencies for the familial DAT subjects differed from the unaffected control groups but the differences were smaller and not statistically significant. These data suggest a previously unrecognized association between the Apo CII TaqI F-allele and familial DAT.

ISSN:0167-7063    

DOI:10.3109/01677068709102337

出版商:Taylor&Francis    

年代:1987

数据来源: Taylor

ISSN:0167-7063    

DOI:10.3109/01677068709102338

出版商:Taylor&Francis    

年代:1987

数据来源: Taylor