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21.
The experimental and clinical data about antibodies against environmental chemical carcinogens and endogenous steroids are represented. The conception of immunomodulation of carcinogens- and steroids-dependent human diseases is proposed. It is postulated that antibodies to polycyclic aromatic hydrocarbons and heterocyclic amines in cooperation with antibodies to cholesterol, sex hormones, mineralo- and glucocorticoids stimulate or inhibit cancer, malformation, cardiovascular and autoimmune diseases depending on their personal combination. It is recommended to use immunoassay of these antibodies for the human diseases prediction. The alternative approaches for prevention using the probiotics transformed by anti-carcinogen antibodies are substantiated. 相似文献
22.
Daniel Duran Xue Zeng Sheng Chih Jin Jungmin Choi Carol Nelson-Williams Bogdan Yatsula Jonathan Gaillard Charuta Gavankar Furey Qiongshi Lu Andrew T. Timberlake Weilai Dong Michelle A. Sorscher Erin Loring Jennifer Klein August Allocco Ava Hunt Sierra Conine Jason K. Karimy Kristopher T. Kahle 《Neuron》2019,101(3):429-443.e4
23.
Clara Serra-Juhé Ivon Cuscó A?da Homs Raquel Flores Núria Torán Luis A Pérez-Jurado 《Epigenetics》2015,10(2):167-177
Congenital heart defects represent the most common malformation at birth, occurring also in ∼50% of individuals with Down syndrome. Congenital heart defects are thought to have multifactorial etiology, but the main causes are largely unknown. We have explored the global methylation profile of fetal heart DNA in comparison to blood DNA from control subjects: an absolute correlation with the type of tissue was detected. Pathway analysis revealed a significant enrichment of differential methylation at genes related to muscle contraction and cardiomyopathies in the developing heart DNA. We have also searched for abnormal methylation profiles on developing heart-tissue DNA of syndromic and non-syndromic congenital heart defects. On average, 3 regions with aberrant methylation were detected per sample and 18 regions were found differentially methylated between groups. Several epimutations were detected in candidate genes involved in growth regulation, apoptosis and folate pathway. A likely pathogenic hypermethylation of several intragenic sites at the MSX1 gene, involved in outflow tract morphogenesis, was found in a fetus with isolated heart malformation. In addition, hypermethylation of the GATA4 gene was present in fetuses with Down syndrome with or without congenital heart defects, as well as in fetuses with isolated heart malformations. Expression deregulation of the abnormally methylated genes was detected. Our data indicate that epigenetic alterations of relevant genes are present in developing heart DNA in fetuses with both isolated and syndromic heart malformations. These epimutations likely contribute to the pathogenesis of the malformation by cis-acting effects on gene expression. 相似文献
24.
25.
Sarah?E.?TurnerEmail author Lisa?Gould David?A.?Duffus 《International journal of primatology》2005,26(6):1435-1457
We studied the relationship between maternal behavior and infant disability in 12 mother-infant dyads for the first 5 weeks
of infant life in the free-ranging Japanese macaque (Macaca fuscata) group on Awaji Island, Japan, from May to September 2001. Congenital limb malformations are prevalent in this population,
and as such carry implications for behavior and conservation. We did not detect any differences in maternal activity budgets,
mother-infant physical contact, infant holding, and overall nursing and infant transport time between mothers of non-disabled
infants, disabled infants that were able to cling to their mothers, and disabled infants whose limb structure prevented clinging.
Mothers of infants with limb malformations severe enough to prevent normal clinging behavior manually supported their infants
during nursing and locomotion significantly more than other mothers did theirs. Increased support-carrying and support-nursing,
and higher frequencies of holding the infant to one's ventrum, suggest that mothers of extensively malformed infants may be
investing more to facilitate the survival of their offspring and that infant disability appears to be influencing maternal
behaviors in this population. 相似文献
26.
Beta-catenin has been implicated in epilepsy because of its altered post seizure expression and the role of Wnt2 signaling in autism. To determine beta-catenin's role in seizure susceptibility, we injected penetylenetetrazol intraperitoneally in beta-catenin cerebral cortex- and hippocampus-specific knockout mice. We then analyzed the latency, number, and duration of four phases of seizure behaviors: (I) non-seizure activity, (II) myoclonic jerks, (III) generalized clonic seizures, and (IV) tonic seizures. The latencies to both death and Phase IV were significantly reduced in mutant mice. Mutant mice also spent significantly more time in Phases III and IV and showed significantly less time in the non-convulsive state (Phase I). Nissl and gold chloride staining indicated that the knockout mice had underdeveloped cortices, lacked a corpus callosum, and were missing hippocampal structures. This suggests that dysfunction of beta-catenin-mediated signaling pathways in mice leads to cortical malformation and increased seizure susceptibility. 相似文献
27.
Vismara C Bacchetta R Di Muzio A Mantecca P Tarca S Vailati G Colombo R 《Birth defects research. Part B, Developmental and reproductive toxicology》2006,77(3):238-243
BACKGROUND: As previously shown, Paraquat (PQ) treatments of Xenopus developing embryos mainly induce a characteristic developmental alteration we named "abnormal tail flexure." PQ oxidative activity has been indicated as the cause of this malformation. Since PQ evokes reactive oxygen species (ROS), among which hydroxyl radicals (OH(*)), and H(2)O(2) can be converted to (OH(*)) via Fenton reaction, we compared here the lethal and teratogenic potentials of both oxidants by using the Frog Embryo Teratogenesis Assay-Xenopus (FETAX), in order to grasp eventual similarities in their teratogenic activity. METHODS: Xenopus embryos were exposed, from stage 8 to stage 47, at 368, 491, 612, and 735 microM H(2)O(2) and 0.388 microM PQ. The probit analysis of H(2)O(2) mortality and malformed larva percents gave a 598.82 microM Lethal Concentration 50% (LC(50)) and 536.04 microM Teratogenic Concentration 50% (TC(50)) from which a 1.11 Teratogenic Index (T.I.) has been calculated. This T.I. value should allow the classification of H(2)O(2) as a non-teratogenic compound. RESULTS: A comparison of H(2)O(2) mortality and malformed larva percents with those obtained from PQ exposure showed the higher embryotoxicity of PQ, but, markedly, both compounds mainly induced the "abnormal tail flexure." Histological analysis of both H(2)O(2) and PQ malformed embryo tails showed a similar distorted morphology of both somites and myocytes. Some of muscle cells were necrotic and affected by an apical enlargement as well as a detachment from the connective tissue of intersomitic boundaries. CONCLUSIONS: In our opinion, both of the tested chemicals likely weaken the mechanical bridge connecting the myocyte contractile apparatus to the extracellular matrix, therefore causing the detachment of some of tail myocytes from their connectival septum as well as their apical enlargement. This could lead to the unbalance of tail tensional forces and, in turn, to the appearance of the "abnormal tail flexure." 相似文献
28.
Cerebral Cavernous Malformation (CCM) is a vascular disease of proven genetic origin, which may arise sporadically or is inherited as an autosomal dominant condition with incomplete penetrance and highly variable expressivity. CCM lesions exhibit a range of different phenotypes, including wide inter-individual differences in lesion number, size, and susceptibility to intracerebral hemorrhage (ICH). Lesions may remain asymptomatic or result in pathological conditions of various type and severity at any age, with symptoms ranging from recurrent headaches to severe neurological deficits, seizures, and stroke. To date there are no direct therapeutic approaches for CCM disease besides the surgical removal of accessible lesions. Novel pharmacological strategies are particularly needed to limit disease progression and severity and prevent de novo formation of CCM lesions in susceptible individuals.Useful insights into innovative approaches for CCM disease prevention and treatment are emerging from a growing understanding of the biological functions of the three known CCM proteins, CCM1/KRIT1, CCM2 and CCM3/PDCD10. In particular, accumulating evidence indicates that these proteins play major roles in distinct signaling pathways, including those involved in cellular responses to oxidative stress, inflammation and angiogenesis, pointing to pathophysiological mechanisms whereby the function of CCM proteins may be relevant in preventing vascular dysfunctions triggered by these events. Indeed, emerging findings demonstrate that the pleiotropic roles of CCM proteins reflect their critical capacity to modulate the fine-tuned crosstalk between redox signaling and autophagy that govern cell homeostasis and stress responses, providing a novel mechanistic scenario that reconciles both the multiple signaling pathways linked to CCM proteins and the distinct therapeutic approaches proposed so far. In addition, recent studies in CCM patient cohorts suggest that genetic susceptibility factors related to differences in vascular sensitivity to oxidative stress and inflammation contribute to inter-individual differences in CCM disease susceptibility and severity.This review discusses recent progress into the understanding of the molecular basis and mechanisms of CCM disease pathogenesis, with specific emphasis on the potential contribution of altered cell responses to oxidative stress and inflammatory events occurring locally in the microvascular environment, and consequent implications for the development of novel, safe, and effective preventive and therapeutic strategies. 相似文献
29.
Masayuki Nakamichi Hisami Nobuhara Toshikazu Nobuhara Minoru Nakahashi Hideo Nigi 《American journal of primatology》1997,42(3):225-234
The birth rate and mortality rate of infants with congenital malformations of the limbs were examined in the Awajishima free-ranging group of Japanese macaques (Macaca fuscata). Of the 606 infants born between 1978 and 1995, 86 (14.2%) were malformed. The male-female ratio did not differ between malformed and normal infants. Most kin-groups included females who gave birth to malformed infants at least once. The mortality rate within the first year after birth for malformed infants (28.2%) was significantly higher than that for normal infants (10.0%). However, this indicates that more than 70% of malformed infants were able to survive for the first year of life, even though they were unable to cling to their mothers ventrum due to their limb deformities. This finding indicates that maternal care-taking is sufficient to enable malformed infants to survive during the early stages of development and that clinging by the infant is not necessary for the display of maternal care. Am. J. Primatol. 42:225–234, 1997. © 1997 Wiley-Liss, Inc. 相似文献
30.
芒果畸形病是芒果上的重要病害之一,由镰孢菌侵染引起,其中以Fusarium mangiferae为主要致病菌.该病害诊断困难,且难于有效控制,因此,一旦发生则对芒果生产造成严重威胁.研究基于ISSR分子标记技术,从50条已知引物中筛选得到一条目的引物UBC 888,该引物可稳定扩增出大小为479bp的F. mangiferae特异性条带(GenBank Accession No. KJ526382).根据获得的特异性片段序列设计引物,成功地将ISSR标记转化为SCAR标记,并获得一对SCAR特异性引物(W342,W1772)和一段大小为1 376bp的特异性扩增片段(GenBank Accession No. KJ526383).通过优化特异性引物扩增条件,获得最适退火温度,构建芒果畸形病病原菌F. mangiferae的快速分子检测技术.此技术操作简单,特异性强,可检测真菌DNA的含量最低为10pg,适用于F. mangiferae和田间带菌芒果组织高灵敏度快速检测,为芒果畸形病的早期诊断和及时预防提供可靠理论依据和技术方法. 相似文献