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81.
Human mini-chromosomes in mouse embryonal stem cells 总被引:3,自引:2,他引:3
We have introduced human mini-chromosomes of 4 Mb and approximately 15 Mb
in size into mouse embryonal stem cells. Although these human mini-
chromosomes are stable in hamster and chicken cells, they re-arrange or
segregate aberrantly in the embryonal stem cells and are rapidly lost in
the absence of selection. However, one of the mini-chromosomes re-
arranged, acquired mouse centromeric sequences and was then stably
maintained for at least 60 population doublings in culture. This mini-
chromosome, which is 4 Mb in size, is a candidate for a mouse germ line
chromosome vector.
相似文献
82.
Sellon DC Knowles DP Greiner EC Long MT Hines MT Hochstatter T Tibary A Dame JB 《Clinical and diagnostic laboratory immunology》2004,11(6):1134-1139
Equine protozoal myeloencephalitis is a progressive neurologic disease of horses most commonly caused by infection with the apicomplexan parasite Sarcocystis neurona. Factors affecting neuroinvasion and neurovirulence have not been determined. We investigated the pathogenesis of infection with S. neurona in horses with severe combined immune deficiency (SCID). Two immunocompetent (IC) Arabian horses and two Arabian horses with SCID were infected orally with 5 x 10(5) sporocysts of S. neurona. Four IC horses and one SCID horse were infected intravenously (i.v.) with 5 x 10(8) merozoites of the WSU-1 isolate of S. neurona. Despite prolonged parasitemia and persistent infection of visceral tissues (skeletal muscle, cardiac muscle, lung, liver, and spleen) as demonstrated by PCR and culture, SCID horses did not develop neurologic signs after oral or i.v. infection. S. neurona was undetectable in the neuronal tissues of SCID horses by either PCR, immunohistochemistry, or culture. In contrast, although parasitemia was undetectable in orally infected IC horses and of only short duration in i.v. infected IC horses, four of six IC horses developed neurologic signs. S. neurona was detectable by PCR and/or culture of neural tissue but not visceral tissue of IC horses with neurologic disease. Infected SCID horses are unable to clear S. neurona from visceral tissues, but the infection does not result in neurologic signs; in contrast, IC horses rapidly control parasitemia and infection of visceral tissues but frequently experience neuroinvasion and exhibit clinical signs of neurologic disease. 相似文献
83.
84.
Louise R Rodino-Klapac Paul ML Janssen Chrystal L Montgomery Brian D Coley Louis G Chicoine K Reed Clark Jerry R Mendell 《Journal of translational medicine》2007,5(1):45-11
Background
Duchenne muscular dystrophy (DMD) is an X-linked recessive disorder with monogenic mutations setting the stage for successful gene therapy treatment. We have completed a study that directly deals with the following key issues that can be directly adapted to a gene therapy clinical trial using rAAV considering the following criteria: 1) A regional vascular delivery approach that will protect the patient from widespread dissemination of virus; 2) an approach to potentially facilitate safe passage of the virus for efficient skeletal muscle transduction; 3) the use of viral doses to accommodate current limitations imposed by vector production methods; 4) and at the same time, achieve a clinically meaningful outcome by transducing multiple muscles in the lower limb to prolong ambulation. 相似文献85.
T Osanai A Konta D Chui T Kanazawa K Onodera T Kogawa 《Archives of pathology & laboratory medicine》1990,114(8):829-831
The ultrastructural characteristics of a benign adrenal adenoma that produces deoxycorticosterone and 11-deoxycortisol were examined by transmission electron microscopy. Both large, round mitochondria with a few cristae in the peripheral portion and spherical or oval mitochondria with sacrotubular cristae were observed in adenoma cells. The development of agranular or granular endoplasmic reticulum varied from cell to cell. In some cells, many vacuoles and collagenous fibers were also seen. Thus, the adrenal tumor we examined was composed of the cells derived from the fascicular zone, which are associated with Cushing's syndrome, and the cells of the glomerular zone observed in association with primary aldosteronism. 相似文献
86.
Mutational analysis of the SOX9 gene in campomelic dysplasia and autosomal sex reversal: lack of genotype/phenotype correlations 总被引:9,自引:1,他引:9
Meyer J; Sudbeck P; Held M; Wagner T; Schmitz ML; Bricarelli FD; Eggermont E; Friedrich U; Haas OA; Kobelt A; Leroy JG; Van Maldergem L; Michel E; Mitulla B; Pfeiffer RA; Schinzel A; Schmidt H; Scherer G 《Human molecular genetics》1997,6(1):91-98
It has previously been shown that, in the heterozygous state, mutations in
the SOX9 gene cause campomelic dysplasia (CD) and the often associated
autosomal XY sex reversal. In 12 CD patients, 10 novel mutations and one
recurrent mutation were characterized in one SOX9 allele each, and in one
case, no mutation was found. Four missense mutations are all located within
the high mobility group (HMG) domain. They either reduce or abolish the
DNA-binding ability of the mutant SOX9 proteins. Among the five nonsense
and three frameshift mutations identified, two leave the C-terminal
transactivation (TA) domain encompassing residues 402-509 of SOX9 partly or
almost completely intact. When tested in cell transfection experiments, the
recurrent nonsense mutation Y440X, found in two patients who survived for
four and more than 9 years, respectively, exhibits some residual
transactivation ability. In contrast, a frameshift mutation extending the
protein by 70 residues at codon 507, found in a patient who died shortly
after birth, showed no transactivation. This is apparently due to
instability of the mutant SOX9 protein as demonstrated by Western blotting.
Amino acid substitutions and nonsense mutations are found in patients with
and without XY sex reversal, indicating that sex reversal in CD is subject
to variable penetrance. Finally, none of 18 female patients with XY gonadal
dysgenesis (Swyer syndrome) showed an altered SOX9 banding pattern in SSCP
assays, providing evidence that SOX9 mutations do not usually result in XY
sex reversal without skeletal malformations.
相似文献
87.
Summary We used the flourescent dye DAPI to visualize nucleoids of chloroplast DNA and follow their behavior through sexual reproduction by counting nucleoids in fixed cells at various stages. Nucleoid number varied greatly among cells at each stage. The mean number of nucleoids per cell was similar in mt
+ and mt
– vegetative cells, and declined similarly during gametogenesis. Longer periods of nitrogen starvation reduced the mean nucleoid number further. Mean nucleoid number declined again in mating pairs, and continued to drop in zygotes up to the latest stage that can be examined (24-h zygotes). The oldest zygotes had means of about 2 to 3 nucleoids in different experiments, significantly fewer than in the mt
+ gametes (usually 4 to 5). The quantitative data on nucleoid number, mating efficiency, and germination efficiency allowed us to show that the decrease in nucleoid number is not limited to gametes that do not mate, or to zygotes that do not germinate. These data are consistant with earlier biochemical studies showing loss of chloroplast DNA during gametogenesis in both mating types, and with the degradation of paternal chloroplast DNA detected biochemically and (in non-quantitative studies) by DAPI staining. There may also be some fusion of nucleoids, although if it occurs it is not complete by 24 h of zygote maturation. 相似文献
88.
Dennis M Edelstein K Copeland K Frederick JA Francis DJ Hetherington R Blaser SE Kramer LA Drake JM Brandt ME Fletcher JM 《Neuropsychology》2005,19(4):456-465
Inhibition of return (IOR) refers to an increase in time to react to a target in a previously attended location. Children with spina bifida meningomyelocele (SBM) and hydrocephalus have congenital dysmorphology of the midbrain, a brain region associated with the control of covert orienting in general and with IOR in particular. The authors studied exogenously cued covert orienting in 8- to 19-year-old children and adolescents (84 with SBM and 37 age-matched, typically developing controls). The exogenous cue was a luminance change in a peripheral box that was 50% valid for the upcoming target location. Compared with controls, children with SBM showed attenuated IOR in the vertical plane, a deficit that was associated with midbrain dysmorphology in the form of tectal beaking but not with posterior brain volume loss. The data add to the emerging evidence for SBM deficits in attentional orienting to salient information. 相似文献
89.
Karen?J?ShermanEmail author Daniel?C?Cherkin Maureen?T?Connelly Janet?Erro Jacqueline?B?Savetsky Roger?B?Davis David?M?Eisenberg 《BMC complementary and alternative medicine》2004,4(1):9
Background
Although back pain is the most common reason patients use complementary and alternative medical (CAM) therapies, little is known about the willingness of primary care back pain patients to try these therapies. As part of an effort to refine recruitment strategies for clinical trials, we sought to determine if back pain patients are willing to try acupuncture, chiropractic, massage, meditation, and t'ai chi and to learn about their knowledge of, experience with, and perceptions about each of these therapies. 相似文献90.
Maureen Handoko Lisa T. Emrick Jill A. Rosenfeld Xia Wang Alyssa A. Tran Alicia Turner John W. Belmont Undiagnosed Diseases Network Brendan H. Lee Carlos A. Bacino Hsiao‐Tuan Chao 《American journal of medical genetics. Part A》2019,179(3):475-479
Genetic alterations leading to overactivation of mammalian target of rapamycin (mTOR) signaling result in brain overgrowth syndromes such as focal cortical dysplasia (FCD) and megalencephaly. Megalencephaly with cutis tri‐color of the Blaschko‐linear type pigmentary mosaicism and intellectual disability is a rare neurodevelopmental disorder attributed to the recurrent mosaic c.5930C > T (p.Thr1977Ile) MTOR variant. This variant was previously reported at low to intermediate levels of mosaicism in the peripheral blood of three unrelated individuals with consistent clinical findings. We report a fourth case of a 3‐year‐old female presenting with megalencephaly, obstructive hydrocephalus due to cerebral aqueductal stenosis, asymmetric polymicrogyria, dysgenesis of the corpus callosum, hypotonia, developmental delay, and cutaneous pigmentary mosaicism. Oligonucleotide and SNP chromosomal microarray (CMA), karyotype, and trio whole exome sequencing (WES) in the peripheral blood, as well as a targeted gene variant panel from fibroblasts derived from hyperpigmented and non‐hyperpigmented skin did not detect any abnormalities in MTOR or other genes associated with brain overgrowth syndromes. Unlike the previously reported cases, the de novo c.5930C > T (p.Thr1977Ile) MTOR variant was detected at 32% mosaicism in our patient only after WES was performed on fibroblast‐derived DNA from the hyperpigmented skin. This case demonstrates the tissue variability in mosaic expression of the recurrent p.Thr1977Ile MTOR variant, emphasizes the need for skin biopsies in the genetic evaluation of patients with skin pigmentary mosaicism, and expands the clinical phenotype associated with this pathogenic MTOR variant. 相似文献