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101.
Association of CHRM2 with IQ: Converging Evidence for a Gene Influencing Intelligence 总被引:1,自引:0,他引:1
Dick DM Aliev F Kramer J Wang JC Hinrichs A Bertelsen S Kuperman S Schuckit M Nurnberger J Edenberg HJ Porjesz B Begleiter H Hesselbrock V Goate A Bierut L 《Behavior genetics》2007,37(2):265-272
The cholinergic neurotransmitter system is thought to be involved in many aspects of memory, attention, and higher cognition.
In the Collaborative Study on the Genetics of Alcoholism (COGA) sample, we have previously reported linkage and association
to the cholinergic muscarinic 2 receptor gene (CHRM2) on chromosome 7 with evoked EEG oscillations (Jones et al. 2004), providing evidence that this gene may be involved in human brain dynamics and cognition. In addition, a small number of
genetic markers were genotyped in CHRM2 in the Minnesota Twin and Family Study (Comings et al. 2003) and a Dutch family study (Gosso et al. 2006, in press) and both research groups found evidence that this gene may be involved in intelligence. In the COGA sample, we
have extensively genotyped SNPs within and flanking the CHRM2 gene. We find evidence of association with multiple SNPs across CHRM2 and Performance IQ, as measured by the Wechsler Adult Intelligence Scale-Revised (WAIS-R). These results remain significant
after taking into account alcohol dependence and depression diagnoses in the sample.
Edited by Danielle Posthuma
Henri Begleiter—Deceased 相似文献
102.
Molecular basis for preferential protective efficacy of antibodies directed to the poorly acetylated form of staphylococcal poly-N-acetyl-beta-(1-6)-glucosamine 下载免费PDF全文
Cerca N Jefferson KK Maira-Litrán T Pier DB Kelly-Quintos C Goldmann DA Azeredo J Pier GB 《Infection and immunity》2007,75(7):3406-3413
Poly-N-acetyl-glucosamine (PNAG) is a staphylococcal surface polysaccharide influencing biofilm formation that is also under investigation for its vaccine potential. Antibodies that bind to PNAG with either low (<15%) or high (>90%) levels of acetate are superior at opsonic and protective activity compared with antibodies that bind to PNAG with only high levels (>70%) of acetate. PNAG is synthesized by four proteins encoded within the intercellular adhesin (ica) locus icaADBC. In Staphylococcus epidermidis, icaB encodes a deacetylase needed for the surface retention of PNAG and optimal biofilm formation. In this study, we confirmed that icaB plays a similar role in Staphylococcus aureus and found that an icaB mutant of S. aureus expressed significantly less surface-associated PNAG, was highly susceptible to antibody-independent opsonic killing that could not be enhanced with antibody raised against deacetylated PNAG (dPNAG), and had reduced survival capacity in a murine model of bacteremia. In contrast, an icaB-overexpressing strain produced primarily surface-associated PNAG, was more susceptible to opsonophagocytosis with antibody to dPNAG, and had increased survival in a murine bacteremia model. The highly acetylated secreted PNAG was more effective at blocking opsonic killing mediated by a human monoclonal antibody (mAb) to native PNAG than it was at blocking killing mediated by a human mAb to dPNAG, which by itself was a more effective opsonin. Retention of dPNAG on the surface of S. aureus is key to increased survival during bacteremia and also provides a molecular mechanism explaining the superior opsonic and protective activity of antibody to dPNAG. 相似文献
103.
104.
Alexandra Elliott Laura Schoenlaub Danielle Freches William Mitchell Guoquan Zhang 《Infection and immunity》2015,83(8):3104-3113
Coxiella burnetii is an obligate intracellular Gram-negative bacterium that causes the zoonotic disease Q fever. Although Q fever is mainly transmitted by aerosol infection, study of the immune responses in the lung following pulmonary C. burnetii infection is lacking. Neutrophils are considered the first immune cell to migrate into the lung and play an important role in host defense against aerosol infection with microbial pathogens. However, the role of neutrophils in the host defense against C. burnetii infection remains unclear. To determine the role of neutrophils in protective immunity against C. burnetii infection, the RB6-8C5 antibody was used to deplete neutrophils in mice before intranasal infection with C. burnetii. The results indicated that neutrophil-depleted mice developed more severe disease than their wild-type counterparts, suggesting that neutrophils play an important role in host defense against C. burnetii pulmonary infection. We also found that neither CXC chemokine receptor 2 (CXCR2) nor interleukin-17 (IL-17) receptor (IL-17R) deficiency changed the severity of disease following intranasal C. burnetii challenge, suggesting that keratinocyte-derived chemokine and IL-17 may not play essential roles in the response to C. burnetii infection. However, significantly higher C. burnetii genome copy numbers were detected in the lungs of IL-1R−/− mice at 14 days postinfection. This indicates that IL-1 may be important for the clearance of C. burnetii from the lungs following intranasal infection. Our results also suggest that neutrophils are involved in protecting vaccinated mice from C. burnetii challenge-induced disease. This is the first study to demonstrate an important role for neutrophils in protective immunity against C. burnetii infection. 相似文献
105.
Arnold Danielle E. Chellapandian Deepak Parikh Suhag Mallhi Kanwaldeep Marsh Rebecca A. Heimall Jennifer R. Grossman Debra Chitty-Lopez Maria Murguia-Favela Luis Gennery Andrew R. Boulad Farid Arbuckle Erin Cowan Morton J. Dvorak Christopher C. Griffith Linda M. Haddad Elie Kohn Donald B. Notarangelo Luigi D. Pai Sung-Yun Puck Jennifer M. Pulsipher Michael A. Torgerson Troy Kang Elizabeth M. Malech Harry L. Leiding Jennifer W. 《Journal of clinical immunology》2022,42(5):1026-1035
Journal of Clinical Immunology - Granulocyte transfusions are sometimes used as adjunctive therapy for the treatment of infection in patients with chronic granulomatous disease (CGD). However,... 相似文献
106.
Jonathan R. Cowart Danielle M. Collins Daniel L. Stanton Gerhard van der Horst Iskande V. Larkin 《Anatomical record (Hoboken, N.J. : 2007)》2022,305(2):446-461
Sperm characteristics, such as sperm morphology and sperm morphometry are important in assessing sperm quality. This is especially important for the management and conservation of endangered and exotic species, like the Florida manatee, where information of this nature is extremely limited. In this study, we fill this knowledge gap to better understand the reproductive physiology of Florida manatees by conducting the first extensive analysis of sperm morphometry and ultrastructure. Sperm were retrieved from the vas deferens of nine recently deceased Florida manatees. Computer-aided sperm morphology analysis (CASMA) was used for morphometric analysis and laser-scanning confocal microscopy and electron microscopy were used for structural and ultrastructural characterization. Our findings reveal new morphometric and structural data for the Florida manatee spermatozoon. Twelve morphometric features of Florida manatee sperm were quantified with some approximately 1.5–2 times larger than those previously reported. Ultrastructurally, the Florida manatee spermatozoon followed a mammalian structural pattern with an ovate-shaped head, midpiece containing 84–90 mitochondria, and a flagellum. However, unique ultrastructural features were identified. Distinct, rectangular-like enlargement of four outer dense fibers surrounding the axoneme was evident, which may provide additional tensile strength to counteract the forces on sperm transiting the female reproductive tract. Likewise, strong localization of F-actin fibers within the midpiece may function to maintain sperm integrity within the female reproductive tract. These findings highlight the potential effects of sexual selective pressures on sperm size and structure in the Florida manatee and provide avenues for research on the occurrence of sperm competition in this species. 相似文献
107.
108.
Perceptual speed does not cause intelligence, and intelligence does not cause perceptual speed 总被引:2,自引:0,他引:2
Luciano M Posthuma D Wright MJ de Geus EJ Smith GA Geffen GM Boomsma DI Martin NG 《Biological psychology》2005,70(1):1-8
There is ongoing debate whether the efficiency of local cognitive processes leads to global cognitive ability or whether global ability feeds the efficiency of basic processes. A prominent example is the well-replicated association between inspection time (IT), a measure of perceptual discrimination speed, and intelligence (IQ), where it is not known whether increased speed is a cause or consequence of high IQ. We investigated the direction of causation between IT and IQ in 2012 genetically related subjects from Australia and The Netherlands. Models in which the reliable variance of each observed variable was specified as a latent trait showed IT correlations of -0.44 and -0.33 with respective Performance and Verbal IQ; heritabilities were 57% (IT), 83% (PIQ) and 77% (VIQ). Directional causation models provided poor fits to the data, with covariation best explained by pleiotropic genes (influencing variation in both IT and IQ). This finding of a common genetic factor provides a better target for identifying genes involved in cognition than genes which are unique to specific traits. 相似文献
109.
Meyer-Fernandes JR Saad-Nehme J Peres-Sampaio CE Belmont-Firpo R Bisaggio DF Do Couto LC Fonseca De Souza AL Lopes AH Souto-Padrón T 《Parasitology research》2004,93(1):41-50
In this work, we describe the ability of living epimastigotes of Trypanosoma cruzi to hydrolyze extracellular ATP. In these intact parasites, there was a low level of ATP hydrolysis in the absence of any divalent metal (2.42±0.31 nmol Pi/h×108 cells). ATP hydrolysis was stimulated by MgCl2, and the Mg-dependent ecto-ATPase activity was 27.15±2.91 nmol Pi/h×108 cells. The addition of MgCl2 to the extracellular medium increased the ecto-ATPase activity in a dose-dependent manner. This stimulatory activity was also observed when MgCl2 was replaced by MnCl2, but not by CaCl2 or SrCl2. The apparent Km for Mg-ATP2– was 0.61 mM, and free Mg2+ did not increase the ecto-ATPase activity. This ecto-ATPase activity was insensitive to the inhibitors of other ATPase and phosphatase activities. To confirm that this Mg-dependent ATPase was an ecto-ATPase, we used an impermeant inhibitor, DIDS (4, 4.diisothiocyanostylbene 2-2-disulfonic acid) as well as suramin, an antagonist of P2 purinoreceptors and inhibitor of some ecto-ATPases. These two reagents inhibited the Mg2+-dependent ATPase activity in a dose-dependent manner. A comparison among the Mg2+-ecto-ATPase activities of the three forms of T. cruzi showed that the noninfective epimastigotes were less efficient at hydrolyzing ATP than the infective trypomastigote and amastigote stages. 相似文献
110.
The posterodorsal preoptic nucleus (PdPN), lateral part of the posterodorsal medial amygdala (MeApd) and medial part of the medial preoptic nucleus (MPNm) are activated at ejaculation in male gerbils as assessed by Fos expression. We sought to immunocytochemically visualize substance P (SP), cholecystokinin (CCK), oxytocin, vasopressin and tyrosine hydroxylase (TH), a catecholaminergic marker, in the mating-activated cells, but the need for colchicine precluded behavioral testing. Instead, we detailed distributions of cells containing these molecules in the medial amygdala, caudal preoptic area and caudal bed nuclei of the stria terminalis (BST) and quantified their densities in the PdPN, MPNm and lateral MeApd for comparison to densities previously assessed for mating-activated efferents from these sites. TH cells were as dense in the PdPN and lateral MeApd as activated efferents to the anteroventral periventricular nucleus. In the lateral MeApd, TH cells were grouped where cells activated at ejaculation are clustered and where CCK cells form a ball. Lateral MeApd CCK cells and PdPN SP cells were as dense as activated efferents to the principal BST. Oxytocinergic PdPN cells and SP cells in the MPNm were as dense as mating-activated efferents to the lateral MeApd. If some oxytocin cells in the PdPN project to the neurohypophysis, as in rats, they could be a source of the oxytocin secreted at ejaculation. Since gerbils are monogamous and biparental, it was also interesting that, unlike monogamous prairie voles, they had few TH cells in the MeApd or dorsal BST, resembling promiscuous rats, hamsters and meadow voles. 相似文献