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1.
MRI and neurological findings in macrocephaly-cutis marmorata telangiectatica congenita syndrome: report of ten cases and review of the literature: We describe the clinical history and magnetic resonance imaging (MRI) findings in 10 children with the Macrocephaly-Cutis Marmorata Telangiectatica Congenita syndrome (M-CMTC--MIM 602501). This syndrome has recently been delineated within the general group of patients with Cutis Marmorata Telangiectatica (CMTC) as a distinct and easily recognisable entity. In contrast to most children with CMTC, patients with M-CMTC syndrome have a high risk of neurological abnormalities, such as hydrocephalus, megalencephaly, developmental delay and mental retardation. An MRI scan showed structural cerebral abnormalities in all of our patients, including megalencephaly, asymmetry of the cerebral hemispheres and abnormally increased signal of white matter. Seven patients also had Chiari type I malformation. Reviewing all reported cases, we propose appropriate surveillance for known complications.  相似文献   

2.
Cutis marmorata telangiectatica congenita (CMTC) is a rare cutaneous disorder. More than one half of the patients with CMTC have additional extra-cutaneous associated congenital anomalies. A subset of patients with CMTC have macrocephaly, the M-CMTC syndrome. This is a report on a patient with the M-CMTC syndrome and a de novo translocation t(2;17)(p11;p13). The etiology and pathology of the M-CMTC syndrome is unknown. Suggestions for the cause for M-CMTC include the occurrence of a new dominant mutation in a single gene, deletion of multiple contiguous genes at a level beyond the resolution of conventional karyotyping and chromosomal mosaicism. This patient did not have chromosomal mosaicism, however he had a translocation. It can be postulated that in the present patient the translocation breakpoints disrupted one or more genes entailing skin lesions but also other features: mental retardation, macrocephaly and facial dysmorphia.  相似文献   

3.
以云斑尖塘鳢为对象,对其扩增片段长度多态性(AFLP)体系中的连接、预扩增、选择扩增等关键步骤的参数进行了对比实验。结果表明,在采用磷酸化接头,预扩增PCR增加延伸反应及20倍稀释预扩增产物的条件下,可得到清晰稳定的电泳图谱。所筛选的48个引物组合中,14个引物组合的产物带型稳定清晰,分布均匀,扩增片段为50-70条。本研究获得的AFLP优化参数及引物能够运用于云斑尖塘鳢群体遗传分析及分子辅助育种研究。  相似文献   

4.
We present an infant with diaphragmatic hernia, anophthalmia and cardiac defect evaluated by magnetic resonance imaging (MRI) autopsy. This female infant was born at 39th weeks by vaginal delivery and presented with diaphragmatic hernia, anophthalmia, cardiac defect and died due to respiratory problems at 28th hours of life. MRI autopsy showed internal organ abnormalities including congenital hernia of the left diaphragm, secondary hypoplasia of the left lung, atrial and ventricular septal defect, dilatation of calices of the kidneys, bilateral anophthalmia, hypoplasia of the optic nerves, hyperintensity of pituitary gland possibly due to bleeding and a cyst of the septum pellucidum. This article shows that MRI autopsy is a valuable method for the evaluation of cases with congenital anomalies if autopsy is not possible.  相似文献   

5.
纬度和土壤微生物对入侵植物加拿大一枝黄花对共同进化的专性食草昆虫抗性的影响在全球化的背景下,入侵植物再次暴露在来自其原产地的专性食草动物面前的可能性越来越大。然而,入侵植物对曾共同进化的专性食草动物的抗性是否存在纬度趋势以及土壤微生物如何影响入侵植物对这类食草动物的抗性还鲜有研究。我们假设入侵植物加拿大一枝黄花(Solidago canadensis)对其曾共 同进化的来自原产地的食草昆虫菊方翅网蝽(Corythucha marmorata)的抗性随纬度的增加而增加,而加拿 大一枝黄花的局部根际微生物可以促进加其对菊方翅网蝽的抗性。为了验证上述假设,我们首先通过野外调查和温室实验,研究了菊方翅网蝽在中国加拿大一枝黄花种群中的分布丰度,以及对加拿大一枝黄花造成的危害是否存在纬度分布规律。其次,我们通过温室实验,检测了加拿大一枝黄花的本地根际土壤微生物是否能促进加拿大一枝黄花对菊方翅网蝽的抗性。研究结果表明,菊方翅网蝽在加拿大一枝黄花中的分布密度和对加拿大一枝黄花的危害程度与纬度以及加拿大一枝黄花的生长呈现正相关,说明加拿大一枝黄花对菊方翅网蝽的抗性具有纬度趋势。然而,在温室实验中,来自不同纬度的加拿大一枝黄花受到菊方翅网蝽的伤害程度没有显著差异。此外,当根际土壤和加拿大一枝黄花的根状茎同时来自于野外被轻度危害的加拿大一枝黄花或同时来自于野外被重度危害的加拿大一枝黄花时,加拿大一枝黄花的抗性最强。这一结果表明,加拿大一枝黄花的局部根际土壤微生物促进了加拿大一枝黄花对菊方翅网蝽的抗性。  相似文献   

6.
The full‐length complementary (c)DNA of vacuolar‐type‐H+‐ATPase B1 gene (vhab1) in marbled eel Anguilla marmorata with 1741 base pairs (bp) was identified. It contained a 1512 bp open reading frame encoding a polypeptide with 503 amino acids (55·9 kDa), an 83 bp 5′‐untranslated region (UTR) and a 146 bp 3′‐UTR. The expression levels of A. marmorata vhab1 in gill and kidney of A. marmorata were evaluated at different intervals during the exposure to various salinities (0, 10 and 25). The results indicated that the expression levels of A. marmorata vhab1 messenger (m)RNA in gill and kidney had a significant increase and reached the highest level at 1 h in brackish water (BW, salinity 10) group and 6 h in seawater (SW, salinity 25) group. Therefore, salinity did affect the relative expression level of A. marmorata vhab1 mRNA in gills, which exhibited the enhancement by c. 44 times in SW group when compared with that in fresh water. No remarkable difference in the expression of A. marmorata vhab1 mRNA was observed after 15 days of SW exposure (P > 0·05). V‐H+‐ATPase activity exhibited an increase by two‐ to three‐fold when compared with that in gill and kidney from the control group. The consequence primarily suggested that A. marmorata vhab1 gene product in elvers from A. marmorata plays an important role in adaptation response to SW.  相似文献   

7.
The population structure of the giant mottled eel, Anguilla marmorata, was investigated with mitochondrial and microsatellite DNA analyses using 449 specimens from 13 localities throughout the species range. Control region F-statistics indicated the North Pacific (Japan, Taiwan, Philippines, Sulawesi), South Pacific (Tahiti, Fiji, New Caledonia, Papua New Guinea), eastern Indian Ocean (Sumatra), western Indian Ocean (Réunion, Madagascar), Ambon, and Guam regions were significantly different (Phi(ST) = 0.131-0.698, P < 0.05) while only a few differences were observed between localities within the South Pacific. These regions were roughly clustered in the neighbour-joining tree, although Ambon individuals were mainly divided into North and South Pacific groups. Analysis with eight microsatellite loci showed almost identical results to those of the control region, except no genetic difference was observed between the western and eastern Indian Ocean (F(ST) = 0.009, P > 0.05). The Bayesian cluster analysis of the microsatellite data detected two genetic groups. One included four North Pacific localities, and the other included eight localities in the South Pacific, Indian Ocean, and Guam, but Ambon individuals were evenly assigned to these two groups. These results showed that A. marmorata has four genetically different populations (North Pacific, South Pacific, Indian Ocean, Guam region). The North Pacific population is fully panmictic whereas the South Pacific and Indian Ocean populations have a metapopulation structure. Interestingly, Guam was suggested to be inhabited by a reproductive population restricted to that region, and the individuals from the North and South Pacific populations co-exist in Ambon.  相似文献   

8.
We describe 15 new variable microsatellites in the freshwater snail Aplexa (Physa) marmorata, as well as conditions for multiplexing and simultaneous genotyping sets of loci. Two to 11 alleles were detected per locus over the five populations studied, and up to eight alleles per locus and population. The observed heterozygosity was extremely low, most probably as the consequence of high selfing rates. The genetic differentiation among populations was large. These markers will constitute efficient tools for investigating the population structure in fragmented habitats. Cross-species amplification in three Physa species (P. acuta, P. fontinalis and P. gyrina) was rather unsuccessful.  相似文献   

9.
Proteolytic fragmentation of [3H]diisopropylfluorophosphate-labelled catalytic subunits of different molecular forms of acetylcholinesterase demonstrates that all forms extracted from the electric organ from Torpedo marmorata are true acetylcholinesterases. This is supported by immunochemical results showing that the radiolabelled polypeptides are readily recognized by specific anti-acetylcholinesterase antibodies. Although distinct structural differences exist, all forms contain a similar peptide carrying the serine hydroxyl of the esteratic subsite. Dimeric, detergent-soluble acetylcholinesterase is present in the low-salt-soluble extract (Mr of the catalytic subunit 66,000) together with a monomeric form (apparent Mr 76,000). This monomeric polypeptide is hydrophilic, enzymatically inactive, and might represent a precursor of the asymmetric forms of acetylcholinesterase.  相似文献   

10.
We analysed phylogeography and population genetic variation across the range of the western pond turtle (Emys marmorata) using rapidly evolving mitochondrial and nuclear DNA sequence data. Nuclear DNA sequences from two unlinked introns displayed extremely low levels of variation, but phylogenetic analyses based on mtDNA recovered four well-supported and geographically coherent clades. These included a large Northern clade composed of populations from Washington south to San Luis Obispo County, California, west of the Coast Ranges; a San Joaquin Valley clade from the southern Great Central Valley; a geographically restricted Santa Barbara clade from a limited region in Santa Barbara and Ventura counties; and a Southern clade that occurs south of the Tehachapi Mountains and west of the Transverse Range south to Baja California, Mexico. An analysis of molecular variance (amova) based on regional hydrographic units revealed that populations from the Sacramento Valley north to Washington were virtually invariant, with no evidence of population substructure among northern river drainage basins. In other areas, E. marmorata contains considerable unrecognized variation, particularly in central and southern California and in northern Baja California, Mexico. Our northern clade is congruent with the distribution of the subspecies Emys marmorata marmorata (Washington-central California). However, no clade is congruent with the distribution of the southern subspecies Emys marmorata pallida from central California-Baja. Thus, recognition of the current subspecies split is not warranted, based on the available genetic evidence. Our amova and phylogenetic results, in conjunction with a growing comparative database for other codistributed aquatic taxa, confirm the occurrence of genetic breaks across the Tehachapi Mountains and Transverse Range bounding the southern end of the Great Central Valley, and point to southern California as a rich source of cryptic genetic variation.  相似文献   

11.
We investigated the presence of cadherins, Ca++ dependent cell-cell adhesion molecules, during the development and maturation of cysts in the testis of the spotted ray Torpedo marmorata. Using different anti-cadherin antibodies, we provide evidence by means of immunohistochemistry and immunoblotting that cadherins are involved in the interaction between Sertoli and germ cells. During the development and maturation of cysts, in fact, cadherins occur between Sertoli and germ cells when they begin to interact to build a cyst. Later on, the presence of cadherins between Sertoli and germ cells persists; furthermore, during the formation of spermatoblast, it is also evident at the level of indentations, arising from Sertoli cells and encompassing germ cells. Finally, the present findings strongly suggest that cadherins are also involved in the spermiogenesis as germ cells, when male gamete differentiation starts, are intensively stained, while, when spermiation is completed, the spermatozoa appear unlabeled.  相似文献   

12.
An antiserum to cholinergic synaptic vesicles isolated from the electric organ of Torpedo marmorata was purified by adsorption with fractions containing unwanted antigens. The adsorbed antiserum responds to the proteoglycan core material of the cholinergic synaptic vesicles. The major antigen migrates in an anomalous fashion on sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE), forming a broad band with an apparent molecular weight of approximately 120,000 - 300,000. The distribution of this antigen after sucrose density gradient centrifugation of synaptic vesicles is the same as that of vesicular ATP. The antigen comigrates with a substance that can be stained with Alcian-Blue after SDS-PAGE of highly purified synaptic vesicles. This substance is related to the low-molecular-weight, Alcian-Blue-positive glycosaminoglycan vesiculin, which is formed from the high-molecular-weight proteoglycan by prolonged dialysis against water or by protease treatment. No antibodies were detected against vesiculin itself, indicating that the antigenic determinants are restricted to the proteoglycan.  相似文献   

13.
Vasoactive intestinal polypeptide (VIP)-like immunoreactivity was detected in the cholinergic electro-motor system of Torpedo marmorata using a combination of immunohistochemical assays, radioimmunoassay, and HPLC. The immunohistochemical assays revealed that the distribution of VIP-like immunoreactivity in the electric lobes, electromotor nerves, and electric organ is comparable to that of the stable cholinergic synaptic vesicle marker vesicle-specific proteoglycan. Ligation of the electromotor nerves caused a marked accumulation of VIP-like immunoreactivity in the lobes (180%) and the proximal portions of the electromotor nerves (130%) and a decrease in the electric organ (-50%), when measured by radioimmunoassay using synthetic VIP (porcine sequence) as the standard. VIP-like immunoreactivity in extracts of electric lobes electromotor nerves, and electric organ was eluted from a semipreparative reverse-phase HPLC column as a single peak with a retention time similar to that of porcine VIP. Rechromatography at higher resolution on an analytical column indicated diversity between the molecular forms of VIP-like immunoreactivity extracted from electric lobe and electric organ, suggesting the possibility of posttranslational processing.  相似文献   

14.
Endogenous phosphorylation of the nicotinic acetylcholine receptor (nAChR) in microsacs from Torpedo marmorata was found to be affected by several reagents commonly used in the preparation of cyclic AMP (cAMP)-dependent protein kinases and in its activity determination. The presence of a Na+,K+-ATPase inhibitor is essential to avoid a rapid depletion of ATP, even when a membrane fraction highly enriched in the nAChR is used. The presence of the thiol reducing agent dithiothreitol was found to abolish the cAMP dependence of nAChR phosphorylation, whereas the less potent reagent 2-mercaptoethanol did not affect the assay. Concentrations in the millimolar range of the chelators EDTA and EGTA were found to inhibit nAChR phosphorylation effectively. This inhibition was not due to a withdrawal of Ca2+ by the chelators, but rather to a reversible inhibition by the Mg2+ complexes. These observations may explain some of the discrepancies found in the literature concerning endogenous and exogenous nAChR phosphorylation.  相似文献   

15.
The presence of Chol-1, an antigen identified in the plasma membrane of cholinergic electromotor nerve terminals of Torpedo marmorata, was investigated in Torpedo electric organ after 3, 6, and 9 weeks' denervation. Denervation was monitored by the cessation of stimulus-evoked discharge potentials, by the reduction in nerve terminals seen morphologically, and by the decrease in ACh and ChAT contents. The content of ganglioside-bound sialic acid did not show any appreciable change with time. Some modification of ganglioside pattern on TLC was observed after 9 weeks' denervation. The presence of Chol-1 after denervation was assayed by its activity in inhibiting the selective complement-induced lysis of the cholinergic subpopulation of guinea pig cortical synaptosome which is mediated by the anti-Chol-1 antiserum. Denervation did not affect Chol-1 immunoreactivity although it did alter the distribution of the immunoreactivity among gangliosides. The possible significance of the results is discussed.  相似文献   

16.
We describe a male neonate with a duplication of 4(q31.3qter) due to unbalanced segregation of a maternal translocation (4;5)(31.3;p15.1). He has a high broad nasal bridge, large, low-set ears, epicanthal folds, long philtrum, retrognathia, high arched palate, wide-spaced nipples, bilateral single transverse palmar creases, bilateral clinodactyly of the fifth finger, right cryptorchidism, and ventricular and secundum type atrial septal defect.  相似文献   

17.
Abstract. 1. Corythucha marmorata (Hemiptera: Tingidae) was more abundant in clusters of small experimental patches of its host plant, goldenrod (Solidago altissima) , than in large patches covering the same area.
2. Adults and egg masses were more abundant on stems on the edges of the patches than on those in the interior.
3. Female Cmarmorata caged on edge plants laid more eggs than females caged on interior plants, and eggs on exposed plants developed faster than those in the middle of a pacth.
4. A preference for edges results in negative 'response' to patch size because large patches invariably have a lower proportion of edge than small patches.  相似文献   

18.
In Taiwanese waters, the morphologically similar elvers of Anguilla japonica and A. marmorata can be distinguished easily at the following loci examined: CK-D *, LDH-B *, sMDH-A * and sMDH-B *. Among these, CK-D * and LDH-B * have fixed allelic differences which can be used as a synoptic key for easy discrimination of the elvers of these two species.  相似文献   

19.
Abstract: Multiple molecular forms of acetylcholinesterase from electric organ and electric lobe of Torpedo marmorata were examined at various developmental stages by sucrose density sedimentation. Four major forms were characterized by their apparent sedimentation coefficients of 6 S, 11 S, 13 S, and 17 S. Embryonic lobe possessed at early stages predominantly the 11 S form. With maturation the 17 S form became the most abundant. The early embryonic stages of the electric organ were characterized by predominating amounts of 6 S and 11 S forms. With differentiation of the postsynaptic membrane of the developing electrocytes, 13 S and 17 S forms replaced the slower-sedimenting forms. Concomitant with the formation of synaptic contacts, a transient increase in the 13 S form was followed by a dramatic accumulation of rapid-sedimenting 17 S form. The establishment of fully functional synapses was accompanied by an increase in the amount of the hydrophobic 6 S form. At birth, equal amounts of 6 S and 17 S form were found, with the other forms present in only trace amounts. The observed characteristic changes correlated with morphological and physiological events, indicating a close functional relationship between the accumulation of the 17 S form and synapse formation and the accumulation of the 6 S form and onset of function.  相似文献   

20.
The membrane-bound acetylcholinesterase (AChE) from the electric organ of Torpedo marmorata was solubilized by Triton X-100 or by treatment with proteinase K and purified to apparent homogeneity by affinity chromatography. Although the two forms differed only slightly in their subunit molecular weight (66,000 and 65,000 daltons, respectively), considerable differences existed between native and digested detergent-soluble AChE. The native enzyme sedimented at 6.5 S in the presence of Triton X-100 and formed aggregates in the absence of detergent. The digested enzyme sedimented at 7.5 S in the absence and in the presence of detergent. In contrast to the detergent-solubilized AChE, the proteolytically derived form neither bound detergent nor required amphiphilic molecules for the expression of catalytic activity. This led to the conclusion that limited digestion of detergent-soluble AChE results in the removal of a small hydrophobic peptide which in vivo is responsible for anchoring the protein to the lipid bilayer.  相似文献   

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