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1.
GPR22 is an orphan G protein-coupled receptor (GPCR). Since the ligand of the receptor is currently unknown, its biological function has not been investigated in depth. Many GPCRs and their intracellular effectors are targeted to cilia. Cilia are highly conserved eukaryotic microtubule-based organelles that protrude from the membrane of most mammalian cells. They are involved in a large variety of physiological processes and diseases. However, the details of the downstream pathways and mechanisms that maintain cilia length and structure are poorly understood. We show that morpholino knock down or overexpression of gpr22 led to defective left-right (LR) axis formation in the zebrafish embryo. Specifically, defective LR patterning included randomization of the left-specific lateral plate mesodermal genes (LPM) (lefty1, lefty2, southpaw and pitx2a), resulting in randomized cardiac looping. Furthermore, gpr22 inactivation in the Kupffer’s vesicle (KV) alone was still able to generate the phenotype, indicating that Gpr22 mainly regulates LR asymmetry through the KV. Analysis of the KV cilia by immunofluorescence and transmission electron microscopy (TEM), revealed that gpr22 knock down or overexpression resulted in changes of cilia length and structure. Further, we found that Gpr22 does not act upstream of the two cilia master regulators, Foxj1a and Rfx2. To conclude, our study characterized a novel player in the field of ciliogenesis. 相似文献
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Michele Salemi Rosita A. Condorelli Corrado Romano Barone Concetta Carmelo Romano Maria Grazia Salluzzo Paolo Bosco Aldo E. Calogero 《Human cell》2014,27(1):43-45
Down’s syndrome (DS), the most common chromosomal disorder, is caused by 21 trisomy and is featured by intellectual disability. Subjects with DS can develop some traits of Alzheimer disease (AD) at an earlier age than subjects without trisomy 21. Apoptosis is a programmed cell death process under both normal physiological and pathological conditions. Caspase-3 (CASP3) plays an important role in neuronal death during nervous system development and under certain pathological conditions. Furthermore, in vitro and in vivo studies report elevated expression and activation of CASP3 in models of AD. On this account, the expression of CASP3 gene was evaluated in cultures of fibroblasts of DS and normal subjects by flow cytometry. CASP3 protein was up-regulated in fibroblasts of DS. The data obtained from this study strengthen the hypothesis that the over-expression of CASP3 gene could have a role in the activation of the apoptotic pathways acting in the neurodegenerative processes in DS. 相似文献
3.
In this investigation, peristaltic flow of Walter’s B fluid in a uniform inclined tube is discussed. The formulation of the
problem is made in a cylindrical coordinate system. The analytical solutions have been calculated by using a regular perturbation
method by taking δ as the perturbation parameter. The expressions for pressure rise and friction forces were calculated using numerical integration.
The graphical results are presented to discuss the various physical quantities of the Walter’s B fluid parameter α, amplitude ratio φ, angle of inclination β and wave length δ. 相似文献
4.
Due to the beaming effect of inlet tube and reflection effect of turbine cover in the turbo molecular pump, the positional and angular distribution of incident gas molecules (IGM) on the turbine blades would no longer be uniformly distributed. Based on the test particle Monte Caro method, a new self-defining procedure is proposed and it can be more accurate to describe the status of IGM into turbine blades. The results show that the influence of rotor speed on the transmission probability is indistinctive. Meanwhile, the incident density between the tip and root of the blades is distinct. The positional beaming effect and the angular beaming effect are enhanced with the lengthening of the tube and less molecule diverge towards the tube wall. The positive transmission probability of first-stage turbine blades using our new method is different from those obeying the cosine distribution under the same number of incident molecules. The calculation results of new method verified by another procedure are reasonable and accurate. 相似文献
5.
Chasing genes in Alzheimer’s and Parkinson’s disease 总被引:4,自引:0,他引:4
Alzheimers disease (AD), the most common type of dementia, and Parkinsons disease (PD), the most common movement disorder, are both neurodegenerative adult-onset diseases characterized by the progressive loss of specific neuronal populations and the accumulation of intraneuronal inclusions. The search for genetic and environmental factors that determine the fate of neurons during the ageing process has been a widespread approach in the battle against neurodegenerative disorders. Genetic studies of AD and PD initially focused on the search for genes involved in the aetiological mechanisms of monogenic forms of these diseases. They later expanded to study hundreds of patients, affected relative-pairs and population-based studies, sometimes performed on special isolated populations. A growing number of genes (and pathogenic mutations) is being identified that cause or increase susceptibility to AD and PD. This review discusses the way in which strategies of gene hunting have evolved during the last few years and the significance of finding genes such as the presenilins, -synuclein, parkin and DJ-1. In addition, we discuss possible links between these two neurodegenerative disorders. The clinical, pathological and genetic presentation of AD and PD suggests the involvement of a few overlapping interrelated pathways. Their imbricate features point to a spectrum of neurodegeneration (tauopathies, synucleinopathies, amyloidopathies) that need further intense investigation to find the missing links. 相似文献
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Yoshiaki Sumiyoshi Masahiko Kikuchi Morishige Takeshita Kohiti Ohshima Yuhiti Masuda 《Virchows Archiv. B, Cell pathology including molecular pathology》1992,61(1):201-207
In Japan, histiocytic necrotizing lymphadenitis (Kikuchi’s disease) is a relatively common reactive lesion affecting lymph
nodes, but the histogenesis and pathogenesis of the disease have not been clarified. Alpha-interferon has a role in the body’s
defense against, viral infections. Using a polyclonal antibody to human alpha-interferon, we found numerous cells, mainly
histiocytes, containing alpha-interferon in affected foci in the lymph nodes from 24 patients with Kikuchi’s disease. Tubuloreticular
structures, thought by some authors to be associated with the production of interferon, were detected by electron microscopy
in histiocytes, activated lymphocytes and vascular endothelial cells in the affected foci. These results suggested that the
formation of tubuloreticular structures is a secondary phenomenon following stimulation by alpha-interferon. Further, the
activity of 2′–5′ oligoadenylate synthetase, which is induced by alpha-interferon and enhanced during the early or active
stage of viral infection, showed increased levels of activity in the active stage of Kikuchi’s disease and decreased to normal
levels in the convalescent stage 2 weeks later. These results suggested the possibility of a viral etiology for Kikuchi’s
disease. 相似文献
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Tsafrir S. Mor 《Biotechnology letters》2015,37(11):2147-2150
Objectives
This short commentary examines the factors that led to Food and Drug Administration’s approval of the first plant-derived biologic.Results
In 2012, the first plant-derived protein pharmaceutical (biologic) was approved for commercial use in humans. The product, a recombinant form of human β-glucocerebrosidase marketed as ELELYSO, was developed by Protalix Biotherapeutics (Carmiel, Israel). The foresight to select this particular therapeutic product for development, flawless production pipeline, and serendipity seem to provide the key in explaining how ELELYSO became the first plant-derived biologic to achieve approval by Food and Drug Administration.Conclusions
While the circumstances that enabled Protalix and its scientists to become the first to arrive at this historic milestone are perhaps unique, it is anticipated that more biologics will follow suit in winning regulatory endorsement.12.
13.
Richard L. Michalski Todd K. Shackelford Catherine A. Salmon 《Human nature (Hawthorne, N.Y.)》2007,18(1):74-84
Using data collected from people with at least one brother and one sister, and consistent with an evolutionary perspective,
we find that older men and women (a) are more upset by a brother’s partner’s sexual infidelity than by her emotional infidelity and (b) are more upset by a sister’s partner’s emotional infidelity than by his sexual infidelity. There were no effects of participant
sex or sex of in-law on upset over a sibling’s partner’s infidelities, but there was an effect of participant sex on reports
of upset over one’s own partner’s infidelities. The results suggest that the key variable among older participants is the
sex of the sibling or, correspondingly, the sex of the sibling’s partner, as predicted from an evolutionary analysis of reproductive
costs, and not the sex of the participant, as predicted from a socialization perspective. Discussion offers directions for
future work on jealousy. 相似文献
14.
A. Iglesias-Vasquez B. Gangloff S. Ruault C. Ribout D. Priddel N. Carlile V. L. Friesen A. Cibois V. Bretagnolle 《Conservation Genetics》2017,18(1):105-115
Seabird life-history traits such as long generation time, low annual fecundity and delayed sexual maturation make them more prone to population loss and consequently to extinction; petrels are indeed amongst the most threatened birds. Based on coalescence and multiloci inference this study examines the extent of genetic differentiation of a vulnerable New Caledonia (caledonica) and Australia (leucoptera) subspecies of Pterodroma leucoptera (Gould’s Petrel), and whether the genetic relationship between them results from the influence of past events like variation in sea level, or is dominated by contemporary gene flow. Sequences of two mitochondrial genes and five nuclear introns were obtained from 86 individuals from both populations. Haplotype networks were used to infer relationships between the haplotypes of both populations. The demographic history of the P. leucoptera complex was studied using neutrality tests and Extended Bayesian Skyline Plots. A weak population differentiation was revealed. The Extended Bayesian Skyline plot suggested a population expansion approximately 80,000 years before present (bp) for caledonica and 30,000 years bp for leucoptera. The split was dated to 30,000 years bp by means of multilocus inference through *BEAST. Despite genetic similarity of the two taxa, we advocate to consider them as independent units for conservation management, given their strong ecological distinctiveness (foraging distribution, winter distribution, breeding phenology and breeding distribution). 相似文献
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Nina Stancheva Jost Weber Josef Schulze Kalina Alipieva Jutta Ludwig-Müller Christiane Haas Vasil Georgiev Thomas Bley Milen Georgiev 《Plant Cell, Tissue and Organ Culture》2011,105(1):79-84
A cell suspension culture of Devil’s claw (Harpagophytum procumbens), a South African plant with high medicinal value, cultivated under submerged conditions showed stable growth and accumulated
high amounts of biomass (18.2 g l−1). Flow cytometry analyses of the suspension’s cell cycle kinetics showed that proportions of cells in G0/G1 and S phases varied insignificantly (between 69–76% and 9–13%, respectively) during the cultivation, while the proportion
of G2/M-phase cells increased until day 8 of cultivation, when the exponential phase of cell growth ended. Metabolite production
in the culture was studied through simultaneous determination of three bioactive phenylethanoid glycosides (verbascoside,
β-OH-verbascoside and leucosceptoside A) by high performance liquid chromatography. It was found that suspended Devil’s claw
cells accumulated mainly verbascoside (517.3 mg l−1), followed by leucosceptoside A (107.1 mg l−1) and β-OH-verbascoside (80.3 mg l−1). In addition, several fatty acids and β-sitosterol were identified in the cell suspension by gas chromatographic-mass spectrometry
analysis. Comparison of the results with previously acquired data for Harpagophytum procumbens transformed roots indicate that cell suspensions cultures are more promising as potential commercial sources of metabolites
such as phenylethanoid glycosides. 相似文献
16.
Rebecca Bliege Bird Brian F. Codding Douglas W. Bird 《Human nature (Hawthorne, N.Y.)》2009,20(2):105-129
Researchers commonly use long-term average production inequalities to characterize cross-cultural patterns in foraging divisions
of labor, but little is known about how the strategies of individuals shape such inequalities. Here, we explore the factors
that lead to daily variation in how much men produce relative to women among Martu, contemporary foragers of the Western Desert
of Australia. We analyze variation in foraging decisions on temporary foraging camps and find that the percentage of total
camp production provided by each gender varies primarily as a function of men’s average bout successes with large, mobile
prey. When men target large prey, either their success leads to a large proportional contribution to the daily harvest, or
their failure results in no contribution. When both men and women target small reliable prey, production inequalities by gender
are minimized. These results suggest that production inequalities among Martu emerge from stochastic variation in men’s foraging
success on large prey measured against the backdrop of women’s consistent production of small, low-variance resources.
Rebecca Bliege Bird received her Ph.D. from UC Davis in 1996. She is interested in gendered strategies of social and economic production, especially as they relate to altruism and public goods provisioning in prestige competitions. In pursuit of these and other questions related to the socioecology of subsistence, she has worked in Torres Strait among the Meriam and is currently working with Martu in Australia’s Western Desert. Brian F. Codding received his B.S. from California Polytechnic State University, San Luis Obispo in 2005 and his M.A. in 2008 from Stanford University, where he is currently a Ph.D. student in the Department of Anthropology. His current research examines the social ecology of gender-specific foraging in archaeological and ethnographic contexts in California and Western Australia. Douglas W. Bird received his Ph.D. from UC Davis in 1996. His interest in ethnoarchaeology led him to explore the processes of shellmidden formation among Meriam of the Torres Strait. He is currently investigating the politics of hunting among Martu and the way that sharing can, paradoxically, create social hierarchy. 相似文献
Douglas W. BirdEmail: |
Rebecca Bliege Bird received her Ph.D. from UC Davis in 1996. She is interested in gendered strategies of social and economic production, especially as they relate to altruism and public goods provisioning in prestige competitions. In pursuit of these and other questions related to the socioecology of subsistence, she has worked in Torres Strait among the Meriam and is currently working with Martu in Australia’s Western Desert. Brian F. Codding received his B.S. from California Polytechnic State University, San Luis Obispo in 2005 and his M.A. in 2008 from Stanford University, where he is currently a Ph.D. student in the Department of Anthropology. His current research examines the social ecology of gender-specific foraging in archaeological and ethnographic contexts in California and Western Australia. Douglas W. Bird received his Ph.D. from UC Davis in 1996. His interest in ethnoarchaeology led him to explore the processes of shellmidden formation among Meriam of the Torres Strait. He is currently investigating the politics of hunting among Martu and the way that sharing can, paradoxically, create social hierarchy. 相似文献
17.
A. S. Gorina L. S. Kolesnichenko V. I. Mikhnovich 《Biochemistry (Moscow) Supplemental Series B: Biomedical Chemistry》2011,5(4):397-401
In a stable state children with Asperger’s and Kanner’s syndromes demonstrate a similar decrease in plasma norepinephrine.
In the aggravated state, these changes become more expressed and are characterized by a decrease in plasma tyrosine, norepinephrine,
normetanephrine, and by an increase in dopamine and homovanillic acid and a decrease in excretion of norepinephrine and an
increase in excretion of homovanillic acid, epinephrine and 3-methoxy-4-hydroxyphenylglycol (MHPG). In the aggravated state
children with Kanner’s syndrome were characterized by increased plasma MHPG, decreased excretion of tyrosine and increased
expression of normetanephrine. The observed imbalance in dopamine and epinephrine/norepinephrine systems suggests importance
of combined analysis of changes in catecholamines and their metabolites as the most informative approach in the study of the
effect of autistic disorders. 相似文献
18.
Maltotriose is metabolized by baker’s and brewer’s yeast only oxidatively, with a respiratory quotient of 1.0, the
being, depending on the strain used, 0–11, as compared with
of 6–42μL CO2 per h per mg dry substance. The transport appeared to proceed by facilitated diffusion (no effects of NaF, iodoacetamide
and 3-chlorophenylhydrazonomalononitrile) with a KT of more than 50mm and was inhibited by maltose > maltotriose > methyl-α-D-glucoside > maltotetraose >D-fruetose >D-glucose. The transport was present constitutively in bothSaccharomyces cerevisiae (baker’s yeast) and inS. uvarum (brewer’s yeast) and it was not significantly stimulated by preincubation with glucose or maltose. The pH optimum was 4.5–5.5,
the temperature dependence yielded an activation energy of 26 kJ/mol. 相似文献
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It is hypothesized from within an evolutionary framework that females should be less invested in peer relations than males. Investment was operationalized as enjoyment in Study 1 and as preference for interaction in Study 2. In the first study, four- and six-year-old children’s enjoyment of peer interaction was observed in 26 groups of same-sex peers. Girls were rated as enjoying their interactions significantly less than boys. In the second study, six- and nine-year-old children were interviewed about the individuals with whom they spend time in their homes and neighborhoods and about the individuals who participate in their favorite activities. The proportion of individuals named by children who were peers was significantly lower for girls than boys both in children’s neighborhoods and in children’s favorite activities. Results strongly support the hypothesis that females and males have evolved differential preferences for interaction with peers. 相似文献