摘要:

Using a double-staining technique with the neuron-specific monoclonal antibody 22C10 and the anti-Ubxmonoclonal antibody FP 3-38 we describe the development of landmark cells in the nervous system ofDrosophila. The staining with MAb 22C10 provides an internal system of reference that allows a precise localization of the most prominentUbxactive cells. The expression ofUbxseems to initiate at the segmental border in the hypoderm and the homologous region in the neuromeres. Also, the extent ofUbxexpression follows quantitative and qualitative changes during embryonic development.

ISSN:0167-7063    

DOI:10.3109/01677068709167179

出版商:Taylor&Francis    

年代:1987

数据来源: Taylor

摘要:

Genes within subdivision 1B of the X-chromosome ofDrosophila melanogasterare known to affect the development of both the central (CNS) and the peripheral (PNS) embryonic nervous system. In this paper we describe the phenotypes of embryos hemizygous for terminal and interstitial deletions of region 1B1-1B10, and of embryos carrying different mutations in certain genes of this region. A minimum of 6 genetic functions that are involved in neural development can be defined in this region. Three of these genes, mapping to thel'sc(a gene of the achaete-scute complex, ASC),elavandvndloci, affect major and apparently different aspects of CNS development. Two additional genes of the ASC,acandscα, also play a role in CNS development, although their participation can only be demonstrated under certain conditions. Finally, in the rightmost part of the region uncovered by the deletionDf(1)260.1, two not yet well separated functions are found to be required for embryonic CNS and compound eye development, respectively. Of these two functions, the embryonic one is similar to the ones ofacandscα, and can therefore be considered as a new element of the ASC.

ISSN:0167-7063    

DOI:10.3109/01677068709167180

出版商:Taylor&Francis    

年代:1987

数据来源: Taylor

摘要:

The motor neuron degeneration (Mnd) is characterized by a progressive deterioration of motor function (stiff-legged gait, abnormal limb placements and grasping, and finally paralysis; moving from rear to forelimbs). There is a dramatic degeneration of spinal cord motor neurons, more severe in the lumbosacral than in the other regions, as well as variable pathology in the lower cranial nerves. Upper motor neurons of the red nucleus, reticular formation of the pons and medulla, and restricted areas of the cerebral cortex are also affected. Degenerating motor neurons share many characteristics seen in the human disease amyotropic lateral sclerosis, including loss of Nissl substance, increases in lipofuscin and abnormal cytoplasmic inclusions. Additionally,Mnd, like ALS, is a disease of later life.

ISSN:0167-7063    

DOI:10.3109/01677068709167181

出版商:Taylor&Francis    

年代:1987

数据来源: Taylor

摘要:

A mouse hybrid cell line (WA17d) was derived which contained multiple copies of human chromosome 21 and no other human chromosome. Cell extracts of this line were prepared and subjected to two-dimensional gel electrophoresis. Several proteins were identified whose synthesis was altered by the presence of chromosome 21 and 6 proteins were identified as being specific to this human chromosome. These gene products might be involved in the pathogenesis of Down syndrome and be related to the neurologic defects and premature aging seen in this common chromosome abnormality.

ISSN:0167-7063    

DOI:10.3109/01677068709167182

出版商:Taylor&Francis    

年代:1987

数据来源: Taylor

摘要:

TheDrosophilamutantoralacks rhodopsin in the R1-6 set of photoreceptors and has a diminution of the photopigment containing rhabdomeres of R1-6. Newly emerged flies have rhabdomeres, albeit small, which extend from the distal rhabdomere cap to the proximal basement membrane. As the fly ages, these are reduced until only distal remnants remain. Carotenoid deprivation does not protectoraflies from rhabdomere loss. When first characterized,orawas designated as a non-formation mutant rather than a degeneration mutant. The truth lies between, since rhabdomeres diminish with age but cells do not die. The plasmalemma of R1-6 have unusual dense striated areas like the“zippers”described earlier for theDrosophilamutantnorpA. Similar membranes are also present within the receptor somata, especially in young flies. The latter probably become internalized from the plasmalemma. They are likely not related to the diminished rhabdomeres as claimed earlier. R7 and R8 have normal rhabdomeres, and in particular, they have normal coated vesicles and multivesicular bodies (MVB's), early steps in the degradation phase of normal rhabdomere maintenance. No MVB's are seen in the R1-6 somata, indicating that the routes for rhabdomere degradation differ from those of normal receptors. However, some MVB-like structures are seen in the intraommatidial cavity. The compound mutantrdgB;orahas a phenotype just like that ofora. This means thatoraprotectsrdgBfrom the light induced degeneration of R1-6 which characterizesrdgB.

ISSN:0167-7063    

DOI:10.3109/01677068709167183

出版商:Taylor&Francis    

年代:1987

数据来源: Taylor

摘要:

The hereditary factors that affect mesencephalic tyrosine hydroxylase (TH) activity were investigated in highly inbred mouse strains (CXBI/ByJ, C57BL/6ByJ, and BALB/cJ). The progenitor strains and their F1hybrids, were compared for mesencephalic TH activity with each other and with replicated F2generations. Quantitative and non-parametric genetic analysis of the data raise the possibility that there is a major gene with robust additive effect that is primarily responsible for the difference between the progenitor strains with intermediate and high mesencephalic TH activity. Strain differences in mesencephalic TH activity have been linked to differences in number of dopamine (DA) neurons in that area. If genetic variation of mesencephalic TH activity is entirely attributable to variation in number of mesencephalic dopamine (DA) neurons, identification of the genetic sources of variation of mesencephalic TH activity may take us a step closer to animal models and preparations that are needed in the study of the physiological and constitutional mechanisms of human disorders in which DA neurotransmission is involved.

ISSN:0167-7063    

DOI:10.3109/01677068709167184

出版商:Taylor&Francis    

年代:1987

数据来源: Taylor

摘要:

A new autosomal recessive mutation, characterized by an early defect in righting reflex and stiffened gait, progression to severe spasticity, tremor and rigidity, and death before weaning, appeared spontaneously on the C57BL/6 background. It was shown to be an allele of the mutant spasticspa, and shall be known asspaAlb. Mutant levels of [3H]strychnine binding are less than 10% of control levels in the brainstem and spinal cord. Autoradiographic examination of the distribution of [3H]strychnine binding sites in the mutant confirm a greatly reduced level of binding compared to control in all areas of the spinal cord, brainstem, and midbrain.

ISSN:0167-7063    

DOI:10.3109/01677068709167185

出版商:Taylor&Francis    

年代:1987

数据来源: Taylor

摘要:

The locus of the structural gene encoding tyrosine hydroxylase,Th, the rate limiting enzyme for catecholamine biosynthesis, was mapped to the distal end of mouse Chromosome (Chr) 7. A DNA probe of genomic origin of rat tyrosine hydroxylase was used to detect restriction fragment length variants among 8 inbred mouse strains. The strain distribution pattern ofThallelic variants in 3 sets of recombinant inbred mouse strains was determined. Comparison of the strain distribution patterns ofThalleles with those of previously typed loci suggestedThwas located on Chr 7. The Chr 7 assignment forThwas confirmed by analyzing 108 mice produced from an (NZB×SM)F1×NZB backcross. Moreover, theThlocus was positioned distally on Chr 7. Mouse Chr 7 and human Chr 11p (the location of the human tyrosine hydroxylase gene) are known to share several homologous loci. With the addition ofTh, the homology between the distal 2/3 of mouse Chr 7 and human Chr 11p appears extensive.

ISSN:0167-7063    

DOI:10.3109/01677068709167186

出版商:Taylor&Francis    

年代:1987

数据来源: Taylor

摘要:

Thirty-nine mentally normal unrelated children diagnosed as having febrile convulsions were included in this study. The following have been carried out: (a) detailed anamnesis and clinical examination; (b) cerebrospinal fluid investigation; (c) EEG examination between attacks; (d) HLA-antigen determination; (e) estimation of serum IgA, IgG, IgM; and (f) counting of percent spontaneous E-rosette formation. The results were statistically compared to normal Egyptian controls. The results could be summarised as follows. (1) Only HLA-B5 antigen frequency is high among patients (χc2= 19.1,P<0.0001). Relative risk is 4.4 which shows significant association (WY2= 29.145,P<0.0001) and etiologic fraction equals 0.377. (2) The means of IgA and E-rosette in the patients were significantly low (t= 3.46,P<0.01 andt= 3.92,P<0.001, respectively), (3) HLA-B5 is the only antigen with high frequency among the two groups of patients with low IgA and E-rosette (χc2= 11.9 and 18.2, respectively). (4) There is a significant association between B5 and low IgA (P0.05). The suggestion is that the genetic control of febrile convulsions is in linkage disequilibrium with HLA-B5, low IgA and low total T-cells. This altered immune function in otherwise normal children with febrile convulsions may predispose them to acute infections and high fever which precipitate convulsions.

ISSN:0167-7063    

DOI:10.3109/01677068709167187

出版商:Taylor&Francis    

年代:1987

数据来源: Taylor