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91.
Background
Bilateral stroke following radiofrequency catheter ablation is an unusual complication and may result in bilateral altitudinal visual field defects. Bilateral altitudinal visual field defects usually result from prechiasmal pathology causing damage to both retinas or optic nerves and rarely from bilateral symmetric damage to the post chiasmal visual pathways.Case presentation
A 48-year-old man complained of visual disturbance on wakening following radiofrequency catheter ablation. The patient had a CHADS score of 1 pre-operatively and no complications were noted intra-operatively. Examination revealed a bilateral superior altitudinal defect and MRI of the brain showed multifocal areas of infarction predominantly involving the occipital lobes which correlated to with the visual deficits.Conclusion
While the risk of thromboembolism and perioperative stroke during radiofrequency catheter ablation is small, it is not insignificant. 相似文献92.
de la Peña LD Lavilla-Pitogo CR Villar CB Paner MG Sombito CD Capulos GC 《Diseases of aquatic organisms》2007,77(3):175-179
Prevalence of white spot syndrome virus (WSSV) was determined using polymerase chain reaction (PCR) methodology on DNA extracted from the gills of wild black tiger shrimp Penaeus monodon collected from 7 sampling sites in the Philippines. These 7 sampling sites are the primary sources of spawners and broodstock for hatchery use. During the dry season, WSSV was detected in shrimp from all sites except Bohol, but during the wet season it was not detected in any site except Palawan. None of the WSSV-PCR positive shrimp showed signs of white spots in the cuticle. Prevalence of WSSV showed seasonal variations, i.e. prevalence in dry season (April to May) was higher than in the wet season (August to October). These results suggest that WSSV has already become established in the local marine environment and in wild populations of P. monodon. Thus, broodstock collected during the dry season could serve as the main source of WSSV contamination in shrimp farms due to vertical transmission of the virus in hatcheries. 相似文献
93.
We show that vasoactive intestinal peptide (VIP) exerts trophic and proangiogenic activities in experimental prostate cancer in vivo. Nude mice were subcutaneously injected with Matrigel impregnated with LNCaP prostate cancer cells. Cell treatment with 100 nM VIP for 1h before xenograft resulted in increased tumor growth after 8 and, more remarkably, 15 days of injection. The same occurred with the mRNA expression of the main angiogenic factor, vascular endothelial growth factor (VEGF), as shown by real-time RT-PCR quantification. The proangiogenic activity of VIP was further established by showing increases of hemoglobin levels, Masson trichromic staining, and immunohistochemical CD34 staining in tumors excised 15 days after subcutaneous injection of VIP-treated cells as compared to control conditions. All these parameters indicate that VIP increases vessel formation. This xenograft model is a useful tool to study in vivo the effects of VIP-related peptides in tumor growth and development of blood supply as well as their therapeutical potential in prostate cancer. 相似文献
94.
Kubrusly RC Ventura AL de Melo Reis RA Serra GC Yamasaki EN Gardino PF de Mello MC de Mello FG 《Neurochemistry international》2007,50(1):211-218
Dopamine is the main catecholamine found in the chick retina whereas norepinephrine is only found in trace amounts. We compared the effectiveness of dopamine and norepinephrine in promoting cyclic AMP accumulation in retinas at embryonic day 13 (E13) and from post-hatched chicken (P15). Dopamine (EC(50)=10microM) and norepinephrine (EC(50)=30microM), but not the beta(1)-adrenergic agonist isoproterenol, stimulated over seven-fold the production of cyclic AMP in E13 retina. The cyclic AMP accumulation induced by both catecholamines in embryonic tissue was entirely blocked by 2microM SCH23390, a D(1) receptor antagonist, but not by alprenolol (beta-adrenoceptor antagonist). In P15 retinas, 100microM isoproterenol stimulated five-fold the accumulation of cAMP. This effect was blocked by propanolol (10microM), but not by 2microM SCH23390. Embryonic and adult retina display beta(1) adrenergic receptor mRNA as detected by RT-PCR, but the beta(1) adrenergic receptor protein was detected only in post-hatched tissue. We conclude that norepinephrine cross-reacts with D(1) dopaminergic receptor with affinity similar to that of dopamine in the embryonic retina. In the mature retina, however, D(1) receptors become restricted to activation by dopamine. Moreover, as opposed to the embryonic tissue, norepinephrine seems to stimulate cAMP accumulation via beta(1)-like adrenergic receptors in the mature tissue. 相似文献
95.
Heritability and genetic correlations of metabolic disease-related phenotypes in Mexico: preliminary report from the GEMM Family Study 总被引:1,自引:0,他引:1
Bastarrachea RA Kent JW Rozada G Cole SA López-Alvarenga JC Aradillas C Brito-Zurita O Cerda-Flores RM Ibarra-Costilla E Gallegos E Laviada-Molina H Hernandez-Escalante V Rosas J Machado A Vadillo F Ramos M Lazalde B Santa-Olalla J MacCluer JW Comuzzie AG 《Human biology; an international record of research》2007,79(1):121-129
Cardiovascular disease (CVD) is a major cause of mortality in the Republic of Mexico, and metabolic syndrome, a complex of CVD risk factors, is increasingly prevalent. To date, however, there have been few studies of the genetic epidemiology of metabolic syndrome in Mexico. As a first step in implementing the GEMM Family Study, a large, multicenter collaborative study, we recruited 375 individuals in 21 extended families, without ascertainment on disease, at 9 medical institutions across Mexico. Participants were measured for anthropometric (stature, weight, waist circumference) and hemodynamic (blood pressure, heart rate) phenotypes; glucose, cholesterol, and triglyceride levels were measured in fasting blood. Variance components-based quantitative genetic analyses were performed using SOLAR. All phenotypes except diastolic blood pressure were significantly heritable. Consistent with the definition of metabolic syndrome, many phenotypes exhibited significant environmental correlation, and significant genetic correlations were found between measures of adiposity and fasting glucose and fasting triglyceride levels. These preliminary data represent the first heritability estimates for many of these phenotypes in the Republic of Mexico and indicate that this study design offers excellent power for future gene discovery relative to metabolic disease. 相似文献
96.
Zogopoulos G Ha KC Naqib F Moore S Kim H Montpetit A Robidoux F Laflamme P Cotterchio M Greenwood C Scherer SW Zanke B Hudson TJ Bader GD Gallinger S 《Human genetics》2007,122(3-4):345-353
Genomic copy number variation (CNV) is a recently identified form of global genetic variation in the human genome. The Affymetrix
GeneChip 100 and 500 K SNP genotyping platforms were used to perform a large-scale population-based study of CNV frequency.
We constructed a genomic map of 578 CNV regions, covering approximately 220 Mb (7.3%) of the human genome, identifying 183
previously unknown intervals. Copy number changes were observed to occur infrequently (<1%) in the majority (>93%) of these
genomic regions, but encompass hundreds of genes and disease loci. This North American population-based map will be a useful
resource for future genetic studies.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
97.
Hydrophobic residues outside the active site of HIV-1 protease frequently mutate in patients undergoing protease inhibitor therapy; however, the mechanism by which these mutations confer drug resistance is not understood. From analysis of molecular dynamics simulations, 19 core hydrophobic residues appear to facilitate the conformational changes that occur in HIV-1 protease. The hydrophobic core residues slide by each other, exchanging one hydrophobic van der Waal contact for another, with little energy penalty, while maintaining many structurally important hydrogen bonds. Such hydrophobic sliding may represent a general mechanism by which proteins undergo conformational changes. Mutation of these residues in HIV-1 protease would alter the packing of the hydrophobic core, affecting the conformational flexibility of the protease. Therefore these residues impact the dynamic balance between processing substrates and binding inhibitors, and thus contribute to drug resistance. 相似文献
98.
Cocoa agroforests that retain a floristically diverse and structurally complex shade canopy have the potential to harbour
significant levels of biodiversity, yet few studies have documented the plant and animal species occurring within these systems
or within landscapes dominated by cocoa production. In this special issue, we bring together nine studies from Latin America,
Africa and Asia that document the contribution of cocoa agroforestry systems to biodiversity conservation, and explore how
the design, management and location of these systems within the broader landscape influence their value as habitats, resources
and biological corridors. Tree diversity within the cocoa production systems is variable, depending on management, cultural
differences, location and farm history, among other factors. Animal diversity is typically highest in those cocoa agroforests
that have high plant diversity, structurally complex canopies, and abundant surrounding forest cover. In general, both plant
and animal diversity within cocoa agroforests is greater than those of other agricultural land uses, but lower than in the
original forest habitat. There are several emerging threats to biodiversity conservation within cocoa production landscapes,
including the loss of remaining forest cover, the simplification of cocoa shade canopies and the conversion of cocoa agroforestry
systems to other agricultural land uses with lower biodiversity value. To counter these threats and conserve biodiversity
over the long-term, land management should focus on conserving native forest habitat within cocoa production landscapes, maintaining
or restoring floristically diverse and structurally complex shade canopies within cocoa agroforests, and retaining other types
of on-farm tree cover to enhance landscape connectivity and habitat availability. 相似文献
99.
Hooper C Day R Slocombe R Handlinger J Benkendorff K 《Fish & shellfish immunology》2007,22(4):363-379
Increasing mariculture of abalone focuses attention on their immune and stress responses. For abalone, as well as many invertebrates, the function and relationship of these systems and how in vitro tests relate to them are not fully understood. This review focuses on research into the immune system and stress response conducted on abalone and on aspects that can be monitored in vitro. To fill the considerable knowledge gaps, we discuss work on other invertebrate taxa, concentrating on those closest to abalone, and making explicit the phylogenetic relations involved. The stress response appears to be very similar to that in vertebrates, but interpreting most immune responses remains problematic. Phylogeny must be considered: immune function tests derived from research into vertebrates or distantly related invertebrates should not be used in abalone until they have been validated in abalone by studies of susceptibility to pathogens. We suggest phagocytic activity of haemocytes and their efficiency in clearing bacteria are reliable parameters to measure, because they have been directly related to immune competency and are consistently depressed by stress. Carefully designed assays of antimicrobial activity may also be useful. Important aims of future research will be to investigate the relationship between growth, stress and robust immunity, and to develop tests that can be run on production animals, which accurately depict immune status. 相似文献
100.
Murciano C Villamón E Yáñez A Murciano J Mir A O'Connor JE Gozalbo D Gil ML 《FEMS immunology and medical microbiology》2007,51(2):327-335
Invasive infections with opportunistic fungi, such as Candida albicans, have become an increasing problem in aged adults in recent years. This work investigates the influence of human ageing on C. albicans recognition by toll-like receptors (TLRs), essential components of the innate immune system, using a cohort of 96 young (15-42 years) and aged (>70 years) human volunteers. No significant differences between aged and young donors were observed on (1) cell surface TLR2, TLR6 and TLR4 expression on lymphocytes, monocytes and granulocytes, (2) production of cytokines [IL-8, IL-1beta, IL-6, IL-10, tumour necrosis factor (TNF)-alpha and IL-12p70] and prostaglandin E(2) (PGE(2)) by whole human blood in response to C. albicans and (3) fungicidal activity of whole blood. A statistically significant higher titre of natural anti-C. albicans antibodies was found in plasma of volunteers between 80 and 95 years old when compared with other age groups, probably as a consequence of the increased levels of serum Ig that has been described in elderly subjects. Therefore, the results indicate that the increased susceptibility to C. albicans infections in the elderly is not a consequence of defects in TLRs expression or signalling, nor of an impaired fungicidal activity of blood. 相似文献