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Léniz A. Portillo M. P. Fernández-Quintela Alfredo Macarulla M. T. Sarasua-Miranda A. del Hoyo M. Díez-López I. 《Journal of physiology and biochemistry》2019,75(3):311-319
Journal of Physiology and Biochemistry - Infants born small for gestational age (SGA) are at increased risk of perinatal morbidity, persistent short stature, and metabolic alterations in later... 相似文献
3.
Fragile X syndrome is a developmental disorder that affects sensory systems. A null mutation of the Fragile X Mental Retardation protein 1 (Fmr1) gene in mice has varied effects on developmental plasticity in different sensory systems, including normal barrel cortical plasticity, altered ocular dominance plasticity and grossly impaired auditory frequency map plasticity. The mutation also has different effects on long-term synaptic plasticity in somatosensory and visual cortical neurons, providing insights on how it may differentially affect the sensory systems. Here we present evidence that long-term potentiation (LTP) is impaired in the developing auditory cortex of the Fmr1 knockout (KO) mice. This impairment of synaptic plasticity is consistent with impaired frequency map plasticity in the Fmr1 KO mouse. Together, these results suggest a potential role of LTP in sensory map plasticity during early sensory development. 相似文献
4.
Amira Alkharusi Elena Lesma Silvia Ancona Eloisa Chiaramonte Thomas Nystr?m Alfredo Gorio Gunnar Norstedt 《PloS one》2016,11(1)
Pulmonary lymphangioleiomyomatosis (LAM) is a rare lung disease caused by mutations in the tumor suppressor genes encoding Tuberous Sclerosis Complex (TSC) 1 and TSC2. The protein product of the TSC2 gene is a well-known suppressor of the mTOR pathway. Emerging evidence suggests that the pituitary hormone prolactin (Prl) has both endocrine and paracrine modes of action. Here, we have investigated components of the Prl system in models for LAM. In a TSC2 (+/-) mouse sarcoma cell line, down-regulation of TSC2 using siRNA resulted in increased levels of the Prl receptor. In human LAM cells, the Prl receptor is detectable by immunohistochemistry, and the expression of Prl in these cells stimulates STAT3 and Erk phosphorylation, as well as proliferation. A high affinity Prl receptor antagonist consisting of Prl with four amino acid substitutions reduced phosphorylation of STAT3 and Erk. Antagonist treatment further reduced the proliferative and invasive properties of LAM cells. In histological sections from LAM patients, Prl receptor immuno reactivity was observed. We conclude that the Prl receptor is expressed in LAM, and that loss of TSC2 increases Prl receptor levels. It is proposed that Prl exerts growth-stimulatory effects on LAM cells, and that antagonizing the Prl receptor can block such effects. 相似文献
5.
A group of lung neuroendocrine (NE) neoplasms are investigated in view of the possible presence of S-100 protein immunoreactivity in their cells. The selected tumours were classified according to Gould et al. (1983a) and Mosca et al. (1985). They comprise 5 carcinoids, 3 neuroendocrine carcinomas of the well-differentiated type, or peripheral carcinoids, 5 neuroendocrine carcinomas of the intermediate cell type, or intermediate-cell, poorly differentiated carcinomas, 3 neuroendocrine carcinomas of the microcytoma type, or small cell carcinomas-SCC and a nodal metastasis of microcytoma. All but 2 tumours were immunoreactive for neuron specific enolase (NSE). Few S-100 immunoreactive cells were detected in 4 out of 5 carcinoids, in 1 out of 3 peripheral carcinoids, in 4 out of 5 poorly differentiated carcinomas and in the 3 microcytomas examined. No S-100 positive cells were found in the SCC's nodal metastasis. The S-100 immunolabelled cells can be interpreted as dendritic reticulum cells migrating through the tumours. However, in one case of typical carcinoid, abundant S-100 positive cells were detected: their stellate morphology and their intimate relation with neoplastic cells suggest that they are part of the neoplasia as a sort of satellite cell. 相似文献
6.
The ratfish,Callorhinchus callorhinchus, a representative of the Holocephali, has a natural serum hemagglutinin (M
r 960 000), composed of heavy (M
r 71000), light (M
r 22 500), and J (M
r 16 000) chains. To approach the mechanisms that generate diversity at this level of evolution, the amino terminal sequence
of the heavy and light chains was determined by automated microsequencing. The chains are unblocked and have modest internal
sequence heterogeneity. The heavy chains show sequence similarity with the terminal region of the heavy chain from the horned
shark,Heterodontus francisci, and other species. In contrast to the heavy chain, the ratfish light chains display low sequence similarity with their shark
kappa counterparts. However, their similarity with the variable region of the chicken lambda light chains is about 75%. 相似文献
7.
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Bocco José L. Panzetta Graciela M. Flury Alfredo Patrito Luis C. 《Molecular biology reports》1988,13(1):45-51
Cell-free translation of polyadenylated mRNA from human term placenta in a wheat germ extract, after immunoprecipitation with antibodies directed against purified pregnant serum SP1, yielded a single polypeptide of 31 kDa. Addition of dog pancreatic microsomal vesicles to the translation system resulted in the appearance of two polypeptides, one of them of 46 kDa and the other of 28 kDa. Both polypeptides were protected from limited proteolysis and when the assay was performed with lytic detergent concentrations in addition to proteases, this protection was abolished indicating that the polypeptides were segregated into the microsomal vesicles. The cleavage of a signal peptide of 3 kDa from the 31 kDa primary translation product gives rise to 28 kDa and accounts for the slight increase in electrophoretic mobility. The treatment of the immunoprecipitated products with Endoglycosidase H and -mannosidase, suggested that only the 46 kDa polypeptide is a glycoprotein.From the results obtained we conclude that SP1 is synthesized and processed to a glycoprotein of 46 kDa which would be a protomeric form of the oligomers reported in pregnant serum by other authors.Abbreviations PMSF
phenylmethyl sulfonylfluoride
- TCA
trichloroacetic acid
- DTT
dithiotreitol 相似文献
9.
Elvira D'Alessandro Corinna De Matteis Vaccarella Maria Luisa Lo Re Francesco Cappa Angela D'Alfonso Stefania Discepoli Maria Rosa Della Penna Giuseppe Del Porto 《Human genetics》1988,80(2):203-204
Summary Pericentric inversion of chromosome 19 has been found in several members of three unrelated families from a restricted geographical region. In one of the families, an additional pericentric inversion of chromosome 9 was observed. Reproductive problems, multiple abortions in two families and a neonatal death in the third, were present. A review of previously described cases is included, and the genetic risk connected with this type of rearrangement is also discussed. 相似文献
10.
I L Krallish Iu E Posmetny? G M Khustaleva B B Re?tblat A I Rapoport 《Mikrobiologiia》1991,60(4):680-685
Addition to the nutrient medium of the extracts of camomile, nettle, mint, or Saint-John's-wort to a concentration of 0.5-4% was established to activate the yeast growth. The maximum effect was recorded on the addition of the extracts to the poor "water" medium. The extracts of camomile and Saint-John's-wort were shown to inhibit the alcohol dehydrogenase activity of the yeast cells, whereas the extracts of nettle and mint increased the activity of this enzyme by 62-70%. 相似文献