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1.
Skott Brill 《Bioethics》2019,33(2):287-293
Some critics of Don Marquis's ‘future‐like‐ours’ anti‐abortion argument launch what has been called the Identity Objection. The upshot of this objection is that under a psychological theory of personal identity, a non‐sentient fetus lacks precisely what Marquis believes gives it a right to life – a future like ours. However, Eric Vogelstein, in a recent article, has argued that under this theory of personal identity a non‐sentient fetus, in fact, has a future like ours, which he believes dissolves the Identity Objection. But Vogelstein is mistaken. Even if he is correct that there is a sense in which a non‐sentient fetus has a future of value under a psychological theory of personal identity, the sense in which it has one is importantly different from the sense in which we have one, meaning that, under such a theory, a non‐sentient fetus does not have a future like ours.  相似文献   

2.
Don Marquis is well known for his future like ours theory (FLO), according to which the killing beings like us is seriously morally wrong because it deprives us of a future we can value. According to Marquis, human fetuses possess a future they can come to value, and thus according to FLO have a right to life. Recently Mark Brown has argued that even if FLO shows fetuses have a right to life, it fails to show that fetuses have a right to use their mother's body, evoking Judith Jarvis Thomson's famous violinist case. In the wake of Brown's conclusion, Marquis presents a new argument—the parenthood argument (PA)—which he believes shows that abortion is seriously morally wrong. Here I argue that the PA fails to show abortion is seriously morally wrong for the same reasons FLO fails to show abortion is seriously morally wrong.  相似文献   

3.
Integrins play a key role in the intermediation and coordination between cells and extracellular matrix components. In this study, we first determined the presence of the β integrin‐like protein and its presumptive ligand, fibronectin‐like protein, during development and in some adult tissues of the bivalve mollusc Mytilus trossulus. We found that β integrin‐like protein expression correlated with the development and differentiation of the digestive system in larvae. Besides the presence of β integrin‐like protein in the digestive epithelial larval cells, this protein was detected in the hemocytes and some adult tissues of M. trossulus. The fibronectin‐like protein was detected firstly at the blastula stage and later, the FN‐LP‐immunoreactive cells were scattered in the trochophore larvae. The fibronectin‐like protein was not expressed in the β integrin‐positive cells of either the veliger stage larvae or the adult mussel tissues and the primary hemocyte cell culture. Despite the β integrin‐ and fibronectin‐like proteins being expressed in different cell types of mussel larvae, we do not exclude the possibility of direct interaction between these two proteins during M. trossulus development or in adult tissues.  相似文献   

4.
Modern treatments of bone injuries and diseases are becoming increasingly dependent on the usage of growth factors to stimulate bone growth. Bone morphogenetic protein‐2 (BMP‐2), a potent osteogenic inductive protein, exhibits promising results in treatment models, but recently has had its practical efficacy questioned due to the lack of local retention, ectopic bone formation, and potentially lethal inflammation. Where a new delivery technique of the BMP‐2 is necessary, here we demonstrate the viability of an elastin‐like peptide (ELP) fusion protein containing BMP‐2 for delivery of the BMP‐2. This fusion protein retains the performance characteristics of both the BMP‐2 and ELP. The fusion protein was found to induce osteogenic differentiation of mesenchymal stem cells as evidenced by the production of alkaline phosphatase and extracellular calcium deposits in response to treatment by the fusion protein. Retention of the ELPs inverse phase transition property has allowed for expression of the fusion protein within a bacterial host (such as Escherichia coli) and easy and rapid purification using inverse transition cycling. The fusion protein formed self‐aggregating nanoparticles at human‐body temperature. The data collected suggests the viability of these fusion protein nanoparticles as a dosage‐efficient and location‐precise noncytotoxic delivery vehicle for BMP‐2 in bone treatment. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:1029–1037, 2016  相似文献   

5.
Perry Hendricks 《Bioethics》2019,33(2):245-253
Much of the debate about the ethics of abortion has centered on whether the fetus is a person. In an attempt to sidestep this complex issue, I argue that, even if the fetus is not a person, abortion is immoral. To arrive at this conclusion, I argue that giving a fetus fetal alcohol syndrome is immoral, and that if this is so, then killing the fetus is immoral. Roughly, this is because killing the fetus impairs it more than giving it fetal alcohol syndrome. Since abortion (in most cases) amounts to killing the fetus, this means that abortion (in most cases) is immoral. I defend the premises of this argument against a plethora of objections, concluding that they either do not work, or commit their proponent to a controversial position.  相似文献   

6.
Dustin Crummett 《Bioethics》2020,34(2):214-220
The ‘impairment argument’ against abortion developed by Perry Hendricks aims to derive the wrongness of abortion from the wrongness of causing foetal alcohol syndrome (FAS). Hendricks endorses an ‘impairment principle’, which states that, if it is wrong to inflict an impairment of a certain degree on an organism, then, ceteris paribus, it is also wrong to inflict a more severe impairment on that organism. Causing FAS is wrong in virtue of the impairment it inflicts. But abortion inflicts an even more severe impairment (death), and so, ceteris paribus, is also wrong. Notably, Hendricks thinks that this argument does not require the claim that the foetus is a person. Here, I respond to Hendricks by arguing that the ceteris paribus clause of the impairment principle is not met in ordinary cases of pregnancy. Carrying an unwanted pregnancy to term is much more burdensome than is refraining from excessive drinking for nine months. This provides a pro tanto justification for obtaining an abortion that does not apply to causing FAS. If the foetus is not a person, it seems fairly clear to me that this justification is strong enough to render abortion permissible. Hendricks is therefore incorrect in claiming that the impairment argument can go without claims concerning foetal personhood. If the foetus is a person, then whether burdensomeness justifies abortion depends on certain questions relating to Thomson’s famous violinist argument. I will not attempt to answer those. But anyone who is otherwise sympathetic to Thomson’s argument should not be moved by the impairment argument.  相似文献   

7.
Eric Reitan 《Bioethics》2016,30(4):272-281
One reason for the persistent appeal of Don Marquis' ‘future like ours’ argument (FLO) is that it seems to offer a way to approach the debate about the morality of abortion while sidestepping the difficult task of establishing whether the fetus is a person. This essay argues that in order to satisfactorily address both of the chief objections to FLO – the ‘identity objection’ and the ‘contraception objection’ – Marquis must take a controversial stand on what is most essential to being the kind of entity that an adult human being is. Such a stand amounts to a controversial account of personhood. To the extent that FLO's success depends on accepting such a controversial metaphysical view, one apparent attraction of FLO proves illusory.  相似文献   

8.
In this project, the toxicity and mechanism of action of the ricin‐B‐related lectin SNA‐I from elderberry (Sambucus nigra) in the pea aphid (Acyrthosiphon pisum) and the beet armyworm (Spodoptera exigua), two important pest insects in agriculture, were studied. SNA‐I is a chimeric lectin belonging to the class of ribosome‐inactivating proteins and consists of an A‐chain with N‐glycosidase activity and a carbohydrate‐binding B‐chain. Incorporation of 2 mg/ml of SNA‐I in the diet of neonates and adults of A. pisum caused 40–46% mortality within 2 days, while in third instars of S. exigua, the larval biomass was significantly reduced by 12% after feeding for 3 days on a diet containing 5 mg/g of SNA‐I. Interestingly, extracts of the (mid)gut of treated A. pisum and S. exigua demonstrated DNA fragmentation and this was accompanied with an increase in caspase‐3‐like activity. The involvement of cell death or apoptosis in the entomotoxicity of SNA‐I through induction of caspase‐3‐like activity was also confirmed by addition of the permeable caspase‐3 inhibitor III in the diet, leading to a rescue of the treated aphid neonates. Finally, similar to the chimeric lectin SNA‐I, the hololectin SNA‐II, consisting of two carbohydrate‐binding B‐chains caused high mortality to neonate A. pisum aphids with an LC50 of 1.59 mg/ml, suggesting that the entomotoxic action of the lectins under study mainly relies on their carbohydrate‐binding activity. © 2010 Wiley Periodicals, Inc.  相似文献   

9.
Fleas are acknowledged vectors and reservoirs of various bacteria that present a wide range of pathogenicity. In this study, fleas collected from wild rodents from the Negev desert in southern Israel were tested for RickettsiaDNA by targeting the 16S rRNA (rrs) gene. Thirty‐eight Xenopsylla ramesis, 91 Synosternus cleopatrae and 15 Leptopsylla flea pools (a total of 568 fleas) were screened. RickettsiaDNA was detected in 100% of the X. ramesis and in one S. cleopatrae flea pools. None of L. algira flea pools was found positive. All positive flea pools were further characterized by sequencing of five additional genetic loci (gltA, ompB, ompA, htrA and fusA). The molecular identification of the positive samples showed all sequences to be closely related to the ‘Rickettsia felis‐like’ organisms (99–100% similarities in the six loci). To further investigate the association between ‘R. felis‐like’ and X. ramesis fleas, ten additional single X. ramesis adult fleas collected from the wild and five laboratory‐maintained X. ramesis imago, five larva pools (2–18 larvae per pool) and two egg pools (18 eggs per pool) were tested for the presence of ‘R. felis‐like’ DNA. All samples were found positive by a specific ompAPCR assay, confirming the close association of this Rickettsia species with X. ramesis in all its life stages. These results suggest a symbiotic association between ‘Rickettsia felis‐like’ and X. ramesis fleas.  相似文献   

10.
A metagenome‐derived glycoside hydrolase family 9 enzyme with an N‐terminal immunoglobulin‐like (Ig‐like) domain, leaf‐branch compost (LC)‐CelG, was characterized and its crystal structure was determined. LC‐CelG did not hydrolyze p‐nitrophenyl cellobioside but hydrolyzed CM‐cellulose, indicating that it is endoglucanase. LC‐CelG exhibited the highest activity at 70°C and >80% of the maximal activity at a broad pH range of 5–9. Its denaturation temperature was 81.4°C, indicating that LC‐CelG is a thermostable enzyme. The structure of LC‐CelG resembles those of CelD from Clostridium thermocellum (CtCelD), Cel9A from Alicyclobacillus acidocaldarius (AaCel9A), and cellobiohydrolase CbhA from C. thermocellum (CtCbhA), which show relatively low (29–31%) amino acid sequence identities to LC‐CelG. Three acidic active site residues are conserved as Asp194, Asp197, and Glu558 in LC‐CelG. Ten of the thirteen residues that form the substrate binding pocket of AaCel9A are conserved in LC‐CelG. Removal of the Ig‐like domain reduced the activity and stability of LC‐CelG by 100‐fold and 6.3°C, respectively. Removal of the Gln40‐ and Asp99‐mediated interactions between the Ig‐like and catalytic domains destabilized LC‐CelG by 5.0°C without significantly affecting its activity. These results suggest that the Ig‐like domain contributes to the stabilization of LC‐CelG mainly due to the Gln40‐ and Asp99‐mediated interactions. Because the LC‐CelG derivative lacking the Ig‐like domain accumulated in Escherichia coli cells mostly in an insoluble form and this derivative accumulated in a soluble form exhibited very weak activity, the Ig‐like domain may be required to make the conformation of the active site functional and prevent aggregation of the catalytic domain.  相似文献   

11.
The somatotropic axis, which includes growth hormone, insulin‐like growth factor (IGF)‐I, and IGF binding proteins (IGFBP), is involved in the regulation of growth and metabolism. Measures of the somatotropic axis can be predictive of nutritional status and growth rate that can be utilized to identify nutritional status of individual animals. Before the somatotropic axis can be a predictive tool, concentrations of hormones of the somatotropic axis need to be established in healthy individuals. To begin to establish these data, we quantified IGF‐I, IGFBP‐2, and IGFBP‐3 in males and females of eight threatened hoofstock species at various ages. Opportunistic blood samples were collected from Bos javanicus (Java banteng), Tragelaphus eurycerus isaaci (bongo), Gazella dama ruficollis (addra gazelle), Taurotragus derbianus gigas (giant eland), Kobus megaceros (Nile lechwe), Hippotragus equines cottoni (roan antelope), Ceratotherium simum simum (white rhinoceros), and Elephas maximus (Asian elephant). Serum IGF‐I and IGFBPs were determined by radioimmunoassay and ligand blot, respectively. Generally, IGF‐I and IGFBP‐3 were greater in males, and IGFBP‐2 was greater in females. In banteng (P = 0.08) and male Nile lechwe (P<0.05), IGF‐I increased with age, but decreased in rhinoceros (P = 0.07) and female Nile lechwe (P<0.05). In banteng, IGFBP‐3 was greater (P<0.01) in males. In elephants (P<0.05) and antelope (P = 0.08), IGFBP‐2 were greater in females. Determination of concentrations of hormones in the somatotropic axis in healthy animals makes it possible to develop models that can identify the nutritional status of these threatened hoofstock species. Zoo Biol 30:275–284, 2011. © 2010 Wiley‐Liss, Inc.  相似文献   

12.
Toll‐like receptors (TLRs) play a key role in the innate immune system. The TLR7, 8, and 9 compose a family of intracellularly localized TLRs that signal in response to pathogen‐derived nucleic acids. So far, there are no crystallographic structures for TLR7, 8, and 9. For this reason, their ligand‐binding mechanisms are poorly understood. To enable first predictions of the receptor–ligand interaction sites, we developed three‐dimensional structures for the leucine‐rich repeat ectodomains of human TLR7, 8, and 9 based on homology modeling. To achieve a high sequence similarity between targets and templates, structural segments from all known TLR ectodomain structures (human TLR1/2/3/4 and mouse TLR3/4) were used as candidate templates for the modeling. The resulting models support previously reported essential ligand‐binding residues. They also provide a basis to identify three potential receptor dimerization mechanisms. Additionally, potential ligand‐binding residues are identified using combined procedures. We suggest further investigations of these residues through mutation experiments. Our modeling approach can be extended to other members of the TLR family or other repetitive proteins.  相似文献   

13.
We characterized the nucleic acid‐sensing Toll‐like receptors (TLR) of a New World bat species, the common vampire bat (Desmodus rotundus), and through a comparative molecular evolutionary approach searched for general adaptation patterns among the nucleic acid‐sensing TLRs of eight different bats species belonging to three families (Pteropodidae, Vespertilionidae and Phyllostomidae). We found that the bat TLRs are evolving slowly and mostly under purifying selection and that the divergence pattern of such receptors is overall congruent with the species tree, consistent with the evolution of many other mammalian nuclear genes. However, the chiropteran TLRs exhibited unique mutations fixed in ligand‐binding sites, some of which involved nonconservative amino acid changes and/or targets of positive selection. Such changes could potentially modify protein function and ligand‐binding properties, as some changes were predicted to alter nucleic acid binding motifs in TLR 9. Moreover, evidence for episodic diversifying selection acting specifically upon the bat lineage and sublineages was detected. Thus, the long‐term adaptation of chiropterans to a wide variety of environments and ecological niches with different pathogen profiles is likely to have shaped the evolution of the bat TLRs in an order‐specific manner. The observed evolutionary patterns provide evidence for potential functional differences between bat and other mammalian TLRs in terms of resistance to specific pathogens or recognition of nucleic acids in general.  相似文献   

14.
In the present research, the effect of indole‐3‐butyric acid (IBA) on the growth, and the production of some primary and secondary metabolites was studied in Nostoc linckia. In this respect, algae cultures were supplied with 0, 0.01, 0.1, 1, 10, and 100 μM IBA for 14 days. IBA at concentrations of 10 and 100 μM induced algal growth expressed as fresh weight in N. linckia. Treatment with IBA at all concentrations stimulated heterocyst formation. In addition, low concentrations of IBA (0.01, 0.1, and 1 μM) had a stimulatory effect on chlorophyll a and carotenoids accumulation. In contrast, higher concentrations of IBA induced the accumulation of phycocyanin, allophycocyanin, and phycoerythrin in the treated algae. In this case, IBA at the concentration of 10 μM was more effective. A significant decrease in protein content was observed in the algae treated by 0.01 μM IBA. All concentrations of IBA caused a decrease in sugar content, but lower concentrations were more effective. IBA application in all of the concentrations except 100 μM increased oligosaccharide‐linked mycosporine‐like amino acids (OS‐MAAs) content. Lower concentrations had a more significant effect on increasing OS‐MAAs content. However the concentrations of 10 and 100 μM IBA decreased scytonemin content. These results indicated the stimulatory impact of IBA on weight, heterocyst formation, and photosynthetic pigments in N. linckia.  相似文献   

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18.
Impairment of glucose‐stimulated insulin secretion (GSIS) caused by glucolipotoxicity is an essential feature in type 2 diabetes mellitus (T2DM). Palmitate and eicosapentaenoate (EPA), because of their lipotoxicity and protection effect, were found to impair or restore the GSIS in beta cells. Furthermore, palmitate was found to up‐regulate the expression level of sterol regulatory element‐binding protein (SREBP)‐1c and down‐regulate the levels of pancreatic and duodenal homeobox (Pdx)‐1 and glucagon‐like peptide (GLP)‐1 receptor (GLP‐1R) in INS‐1 cells. To investigate the underlying mechanism, the lentiviral system was used to knock‐down or over‐express SREBP‐1c and Pdx‐1, respectively. It was found that palmitate failed to suppress the expression of Pdx‐1 and GLP‐1R in SREBP‐1c‐deficient INS‐1 cells. Moreover, down‐regulation of Pdx‐1 could cause the low expression of GLP‐1R with/without palmitate treatment. Additionally, either SREBP‐1c down‐regulation or Pdx‐1 over‐expression could partially alleviate palmitate‐induced GSIS impairment. These results suggested that sequent SREBP‐1c‐Pdx‐1‐GLP‐1R signal pathway was involved in the palmitate‐caused GSIS impairment in beta cells. J. Cell. Biochem. 111: 634–642, 2010. © 2010 Wiley‐Liss, Inc.  相似文献   

19.
Abstract The brown planthopper (BPH), Nilaparvata lugens Stål, which is one of the most destructive pests of rice, has been confirmed to harbor yeast‐like symbiotes (YLS) in the fat body. Several morphologically different YLS have been previously isolated and cultured in vitro from BPH, but direct evidence is lacking to further clarify whether the cultured YLS were from BPH. In this study, one species of YLS was successfully cultured in vitro and simultaneously verified to exist in the fat body of BPH by sequence analysis and nested polymerase chain reaction (PCR). The cultured YLS isolate in vitro was identified as a member of the genus Candida on the basis of 18S rDNA (ribosomal DNA) and 5.8S‐ITS (internal transcribed spacer) rDNA sequence and a phylogenetic analysis of ITS sequences from yeast. Therefore, this yeast isolate was named as Candida‐like symbiotes. Candida‐like symbiotes was found to exist in fat bodies, ovaries and newly laid eggs of the BPH, but not in the heads, thoraxes and mid‐guts. In addition, the number of Candida‐like symbiotes in 1 × 106 of purified YLS from BPH fat bodies was speculated to be (5.32 ± 0.22) × 104 on the basis of a quantitative PCR analysis.  相似文献   

20.
Fibrinogen‐like protein 2 (FGL2) has been reported to play a key role in the development of human cancers. However, it is still unmasked whether FGL2 plays a potential role in colorectal carcinogenesis. In this study, the messenger RNA and protein expression levels were measured by quantitative real‐time polymerase chain reaction and western blot. Cell counting kit‐8 assay, transwell migration, and invasion assay were carried out to evaluate the proliferation, migration, and invasion of LOVO and SW620 cells. FGL2 was upregulated in colorectal cancer (CRC) tissues, as well as cell lines. Mitogen‐activated protein kinase (MAPK) signaling was activated in CRC tissues and cell lines. FGL2 was confirmed to be downregulated by MAPK signaling inhibitor U0126. Further, we determined that knockdown of FGL2 caused a reduction of proliferation, migration, and invasion in LOVO and SW620 cells. Consistently, treatment of LOVO and SW620 cells with U0126 led to a decrease in cell proliferation, migration, and invasion. However, these changes initiated by U0126 were abolished by FGL2 overexpression. To conclude, MAPK‐mediated upregulation of FGL2 promotes the proliferation, migration, and invasion of CRC cells.  相似文献   

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