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1.
The effects of 19-hydroxy-prostaglandins (19-OH-PGs) were tested invivo on the rabbit oviduct and uterus and on the rhesus monkey (Macacamulatta) uterus. The 19-OH-PGEs suppressed spontaneous oviductal and uterine activity in the rabbit. The qualitative effect on the rabbit oviduct of 19-OH-PGEs was similar to that of PGE2. However, the typical response of the rabbit uterus to PGE2 was an increase in muscle activity. With regard to the rabbit oviduct, 19(R)-OH-PGE2 was as potent as PGE2, but 19(S)-OH-PGE2 was approximately 12 as potent as PGE2. Based on the dose of 19-OH-PGEs usually required to cause a minimal suppression and the dose of PGE2 required to cause a minimal stimulation of rabbit uterine activity, 19(R)-OH-PGE2 was twice as potent as PGE2 while 19(S)-OH-PGE2 was 12 as potent as PGE2. Stimulatory effects on the rabbit oviduct and uterus were observed following administration of 19-OH-PGEs and PGF. The potency on the rabbit oviduct of 19(S)-OH-PGF was about 15 to 110 that of PGF; the potency of 19(R)-OH-PGF was about 110 to 120 that of PGF. Both 19-OH-PGFs were approximately 15 to 110 as potent as PGF on the rabbit uterus. At the doses tested 19-OH-PGFs were inactive on the monkey uterus. Thus, these compounds are at least 15 as active as PGF. In contrast, 19(R)-OH-PGE2 had approximately the same potency as PGE2 in stimulating monkey uterine activity; but 19(S)-OH-PGE2 was approximately 13 as potent as PGE2.  相似文献   

2.
Desulfovibrio HL21 is unable to grow with amino acids as energy substrates. Alanine, serine, aspartate and to some extent glutamate were used as carbon and nitrogen sources in the presence of hydrogen as the energy substrate. Dense cell suspensions converted alanine stoichiometrically to acetate, NH 4 + and presumably HCO 3 - , but at a very low rate. Desulfovibrio HL21 cells grown with alanine as carbon and nitrogen source contained increased levels of NAD(P)-dependent l-alanine dehydrogenase as compared to cells grown with NH4Cl as nitrogen source. Unfavourable kinetic properties of this alanine dehydrogenase, repression of the synthesis of the enzyme by NH 4 + and a low rate of NADH oxidation all have a negative effect on the rate of degradation of alanine and may partly explain the inability of the strain to grow with alanine as an energy substrate.  相似文献   

3.
4.
AimThe objective of this research was to estimate the dose distribution delivered by radioactive gold nanoparticles (198AuNPs or 199AuNPs) to the tumor inside the human prostate as well as to normal tissues surrounding the tumor using the Monte-Carlo N-Particle code (MCNP-6.1.1 code).BackgroundRadioactive gold nanoparticles are emerging as promising agents for cancer therapy and are being investigated to treat prostate cancer in animals. In order to use them as a new therapeutic modality to treat human prostate cancer, accurate radiation dosimetry simulations are required to estimate the energy deposition in the tumor and surrounding tissue and to establish the course of therapy for the patient.Materials and methodsA simple geometrical model of a human prostate was used, and the dose deposited by 198AuNPs or 199AuNPs to the tumor within the prostate as well as to the healthy tissue surrounding the prostate was calculated using the MCNP code. Water and A-150 TEP phantoms were used to simulate the soft and tumor tissues.ResultsThe results showed that the dose due to 198AuNPs or 199AuNPs, which are distributed homogenously in the tumor, had a maximal value in the tumor region and then rapidly decreased toward the prostate–tumor interface and surrounding organs. However, the dose deposited by 198Au is significantly higher than the dose deposited by 199Au in the tumor region as well as normal tissues.ConclusionsAccording to the MCNP results, 198AuNPs are a promising modality to treat prostate cancer and other cancers and 199AuNPs could be used for imaging purposes.  相似文献   

5.
Biological technologies are becoming an important part of the economy. Biotechnology already contributes at least 1% of US GDP, with revenues growing as much as 20% annually. The introduction of composable biological parts will enable an engineering discipline similar to the ones that resulted in modern aviation and information technology. As the sophistication of biological engineering increases, it will provide new goods and services at lower costs and higher efficiencies. Broad access to foundational engineering technologies is seen by some as a threat to physical and economic security. However, regulation of access will serve to suppress the innovation required to produce new vaccines and other countermeasures as well as limiting general economic growth.
Robert CarlsonEmail:
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6.
Wang  Junren  Li  Hua  Yu  Haili  He  Yi 《Plasmonics (Norwell, Mass.)》2020,15(6):1827-1833

Considerable efforts have been made to develop reactive oxygen species (ROS) scavengers for removing high level of ROS. However, most of the reported ROS scavengers are nondegradable and involve harsh reaction conditions as well as utilize various surface ligands. In order to overcome these drawbacks, in the present work, we develop a facile and mild synthesis avenue for preparation of surface-clean hydrogen-doped molybdenum oxide (H0.34MoO3) via simply mixing MoO3 dispersion with aluminum foil under an acidic environment without any surface capping reagents at room temperature. The resulting H0.34MoO3 can act as a broad-spectrum ROS scavenger, including .OH, H2O2, O2, and 1O2 as well as 2, 2-diphenyl-1-picrylhydrazyl (DPPH). The free radical scavenging activity of H0.34MoO3 achieves as high as 71.6% and 99.1% for .OH and DPPH scavenging, which is comparable and superior to that of ascorbic acid that is a classic free radical scavenger. More significantly, the resulting H0.34MoO3 is degrade, which can be degraded into molybdate ions under a neutral environment (pH 7.4).

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7.
Buoyant density gradient centrifugation has been used to separate bacteria from complex food matrices, as well as to remove compounds that inhibit rapid detection methods, such as PCR, and to prevent false-positive results due to DNA originating from dead cells. Applying a principle of buoyant density gradient centrifugation, we developed a method for rapid separation and concentration following filtration and low- and high-speed centrifugation, as well as flotation and sedimentation buoyant density centrifugation, for 12 food-borne pathogens (Salmonella enterica, Escherichia coli, Yersinia enterocolitica, Campylobacter jejuni, Vibrio cholerae O139, Vibrio parahaemolyticus O3K6, Vibrio vulnificus, Providencia alcalifaciens, Aeromonas hydrophila, Bacillus cereus, Staphylococcus aureus, and Clostridium perfringens) in 13 different food homogenates. This method can be used prior to real-time quantitative PCR (RTi-qPCR) and viable-cell counting. Using this combined method, the target organisms in the food samples theoretically could be concentrated 250-fold and detected at cell concentrations as low as 101 to 103 CFU/g using the RTi-qPCR assay, and amounts as small as 100 to 101 CFU/g could be isolated using plate counting. The combined separation and concentration methods and RTi-qPCR confirmed within 3 h the presence of 101 to 102 CFU/g of Salmonella and C. jejuni directly in naturally contaminated chicken and the presence of S. aureus directly in remaining food items in a poisoning outbreak. These results illustrated the feasibility of using these assays for rapid inspection of bacterial food contamination during a real-world outbreak.  相似文献   

8.
The investigation was carried out to evaluate the effect of different doses of gamma rays (100, 200, 300, 400, 500 Gy and zero doses as control) on various morphological aspects of Abelmoschus esculentus. A comparison of the results of different doses with control showed that gamma irradiation significantly affected various parameters. Days to germination were almost the same as compared to control, but 400 Gy took minimum days to germination. Germination % was 100% both in control and the irradiated plants. 100 Gy took minimum days for flower initiation as compared to control and other doses. Fruit initiation early occurred in 100Gy as compared to other doses, and fruit maturation occurred early in 300 Gy as compared to control. Plant height was significantly increased at 500 Gy as compared to control. Number of fruits per plant was significantly decreased at 200 Gy as compared to control. Fruit length decreased in all doses but in control fruit length was maximum. Number of seeds per fruit was maximum at control, fresh and dry weights of seeds were increased in control as compared to other doses. The number of nodes decreased in all doses but in the control the numbers of nodes were maximum. Branches were increased in100Gy as compare to 200, 300,400,500 Gy as well in control. Numbers of leaves were increased in 300 Gy as compared to other doses.  相似文献   

9.
Following recent arguments that there is no logical problem with attributing mental or agential states to animals, I address the epistemological problem of how to go about making accurate attributions. I suggest that there is a two-part general method for determining whether a psychological property can be accurately attributed to a member of another species: folk expert opinion and functionality. This method is based on well-known assessments used to attribute mental states to humans who are unable to self-ascribe due to an early stage of development or impairment, and can be used to describe social and emotional development as well as personality. I describe how instruments such as the Child Behavior Checklist, which relies on intersubjective expert opinion, could be modified to assess other species subjects. The measures are validated via the accuracy of the predictions that are derived, which is an example of the functionality of attribution. I respond to theoretical criticisms against use of this method, and argue that if the method counts as good science for infant cognition research, then it should count as good science for animal cognition research as well. Correspondingly, if the method doesn’t count as good science for animal cognition research, then we must be very skeptical of its use with nonverbal humans.
Kristin AndrewsEmail:
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10.
It is common to portray conservative and liberal Protestant denominations as “strong” and “weak” on the basis of indices such as church attendance. Alternatively, they can be regarded as qualitatively different cultural systems that coexist in a multiple-niche environment. We integrate these two perspectives with a study of American teenagers based on both one-time survey information and the experience sampling method (ESM), which records individual experience on a moment-by-moment basis. Conservative Protestant youth were found to be more satisfied, family-oriented, and sociable than liberal Protestant youth, but also more dependent on their social environment, which is reflected in a deterioration of their mood when they are alone. Liberal Protestant youth appear to have internalized values that remain constant whether in the presence or absence of others. We relate these results to the social scientific literature on liberalism and conservatism and to evolutionary theory as a framework for explaining cultural systems as adaptations to multiple-niche environments.
David Sloan WilsonEmail:
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11.
12.
Diversely functionalized, fused aryl–alkyl ring systems hold a prominent position as well-established molecular frameworks for a variety of anti-cancer agents. The benzosuberene (6,7 fused, also referred to as dihydro-5H-benzo[7]annulene and benzocycloheptene) ring system has emerged as a valuable molecular core component for the development of inhibitors of tubulin assembly, which function as antiproliferative anti-cancer agents and, in certain cases, as vascular disrupting agents (VDAs). Both a phenolic-based analogue (known as KGP18, compound 39) and its corresponding amine-based congener (referred to as KGP156, compound 45), which demonstrate strong inhibition of tubulin assembly (low micromolar range) and potent cytotoxicity (picomolar range for KGP18 and nanomolar range for KGP156) are noteworthy examples of such benzosuberene-based compounds. In order to extend the structure–activity relationship (SAR) knowledge base related to benzosuberene anti-cancer agents, a series of eleven analogues (including KGP18) were prepared in which the methoxylation pattern on the pendant aryl ring as well as functional group incorporation on the fused aryl ring were varied. The synthetic approach to these compounds featured a sequential Wittig olefination, reduction, Eaton’s reagent-mediated cyclization strategy to achieve the core benzosuberone intermediate, and represented a higher-yielding synthesis of KGP18 (which we prepared previously through a ring-expansion strategy). Incorporation of a fluorine or chlorine atom at the 1-position of the fused aryl ring or replacement of one of the methoxy groups with hydrogen (on the pendant aryl ring of KGP18) led to benzosuberene analogues that were both strongly inhibitory against tubulin assembly (IC50 approximately 1.0 μM) and strongly cytotoxic against selected human cancer cell lines (for example, GI50 = 5.47 nM against NCI-H460 cells with fluoro-benzosuberene analogue 37). A water-soluble phosphate prodrug salt of KGP18 (referred to as KGP265, compound 44) and a water-soluble serinamide salt (compound 48) of KGP156 were also synthesized and evaluated in this study.  相似文献   

13.
Gastric cancer is the third leading cause of cancer death with 5-year survival rate of about 30–35%. Since early detection is associated with decreased mortality, identification of novel biomarkers for early diagnosis and proper management of patients with the best response to therapy is urgently needed. Long noncoding RNAs (lncRNAs) due to their high specificity, easy accessibility in a noninvasive manner, as well as their aberrant expression under different pathological and physiological conditions, have received a great attention as potential diagnostic, prognostic, or predictive biomarkers. They may also serve as targets for treating gastric cancer. In this review, we highlighted the role of lncRNAs as tumor suppressors or oncogenes that make them potential biomarkers for the diagnosis and prognosis of gastric cancer. Relatively, lncRNAs such as H19, HOTAIR, UCA1, PVT1, tissue differentiation-inducing nonprotein coding, and LINC00152 could be potential diagnostic and prognostic markers in patients with gastric cancer. Also, the impact of lncRNAs such as ecCEBPA, MLK7-AS1, TUG1, HOXA11-AS, GAPLINC, LEIGC, multidrug resistance-related and upregulated lncRNA, PVT1 on gastric cancer epigenetic and drug resistance as well as their potential as therapeutic targets for personalized medicine was discussed.  相似文献   

14.
Studies on plant products have revealed that many of them may either act as fungicides,1,2) insecticides,3)chemosterilants,4,5) moluscicides,6) bactericides7) or as virucides.8) Although there are a number of reports on natural inhibitors of germination and growth,9) and on allelochemics,10) little work seems to have been done with respect to their possible selective effects, hence to their possible use as selective weedicides. Here we report a plant product that many act as a selective weedicide.  相似文献   

15.
The effects of CCC on the 32 P amounts absorbed by cotton seedlings were studied. CCC was applied to the seedlings either as spray or as addition to the nutrient solution in concentrations of 0, 25, 50, 100 and 200 mg/1. 32P was added to the medium as KH232P O4 in the concentration of 40 μCi/50 ml. During the experimental period, no morphological changes were observed. The total 32P uptake was inhibited in CCC treated seedlings. The application of CCC, both as spray and as addition to the medium, led to an accumulation of 32P in stem, but to a decrease in root. The leaves showed different responses to different methods of application; spraying increased, while an addition of CCC to the medium decerases the 32P content in the leaves. It is concluded that CCC inhibits 32P uptake, whereas it ac accelerates the 32P translocation from root to the aerial parts.  相似文献   

16.
The presence of transforming growth factor β1 (TGF-β1) for 24 or 48 h stimulated DNA synthesis, the percentage of cells in the S + G2/M phases of the cell cycle, and cell number, as compared to quiescent cells. The mitogenic capacity of TGF-β1 (1 pM) was similar to that shown by 10% fetal calf serum (FCS). TGF-β1 for 48 h increased by 5-fold the percentage of cells containing (3H)thymidine-labeled nuclei as compared to quiescent cells. In addition, single fetal brown adipocytes, showing their typical multilocular fat droplets phenotype, become positive for (3H)thymidine-labeled nuclei in response to TGF-β1. Moreover, TGF-β1 induced the mRNA expression of a complete set of proliferation-related genes, such as c-fos (30 min), c-myc and β-actin (2 h), and H-ras, cdc2 kinase, and glucose 6-phosphate dehydrogenase (G6PD) at 4 and 8 h, as compared to quiescent cells. Concurrently, TGF-β1 for 12 h increased the protein content of proliferating cellular nuclear antigen (PCNA) by 6-fold and p21-ras by 2-fold. Although our results demonstrate that TGF-β1 induces the expression of very early genes related to cell proliferation, TGF-β1 could be acting either as a mitogen or as a survival factor to induce proliferation in fetal brown adipocytes. © 1996 Wiley-Liss, Inc.  相似文献   

17.
The pollen content of eleven honey samples from ten different apiaries in the Baixa Limia – Serra do Xurés Nature Reserve and other honey commercialised by the cooperative as “Mel do Xurés” (north‐west Spain) was subjected to quantitative and qualitative melissopalynological analysis. The quantitative analysis found that ten samples belonged to Maurizio's Class III and one to Class IV. According to the qualitative analysis, four samples were classified as unifloral honey with Erica, four samples as multifloral honey with Erica pollen as the principal component and three samples as multifloral honey with Cytisus‐type pollen and Erica as the principal component pollen. The pollen spectra differ between the diverse honeys analysed, with a common denominator being Erica and Cytisus‐type pollen being abundant in all. For the rest of the samples, the pollen spectra were mainly the same, but with different relative percentages among secondary elements. Thus, either as a secondary or an important element, 91% of the honeys contained Quercus, 82% Castanea sativa Miller, 45% Rubus, 36% Cistus and 27% Lithodora prostrate (Loisel) Griseb,. In particular, we record for the first time the presence of Ribes and Ilex aquifolium L. pollen in Spanish honeys as an important minor or minor pollen component.  相似文献   

18.
Summary Four genes concerned with the resistance of wild-type Micrococcus radiodurans to the lethal action of mitomycin-C (MTC), mtcA, mtcB, uvsA and uvsB, have been identified by isolating mutants sensitive to MTC.Two strains of M. radiodurans, 302 and 262 carrying mutations in mtcA and mtcB respectively, are between forty and sixty times as sensitive as the wild-type to MTC, only slightly more sensitive than the wild-type to ionizing () radiation and have the same resistance as the wild-type to ultraviolet (u.v.) radiation. Strain 302 can be transformed at a high frequency to wild-type resistance to MTC with DNA from strain 262, and vice versa, indicating that mtcA and mtcB have different genetic locations.Two further strains of M. radiodurans, 303 and 263 having mutations in uvsA and uvsB respectively are only from four to eight times as sensitive as the wild-type to MTC, seven to thirteen times as sensitive to -radiation but between twenty to thirty-three times as sensitive to u.v. radiation. Strain 303 can be transformed with DNA from strain 263, or vice versa, to wild-type resistance to u.v. radiation, implying that uvsA and uvsB also have different genetic locations. M. radiodurans strain 301 which is mutant in both mtcA and uvsA, and strain 261 which is mutant in mtcB and uvsB are twenty to forty times as sensitive as the wild-type to both MTC and u.v. radiation and seven to ten times as sensitive to radiation. Neither mtcA and uvsA nor mtcB and uvsB are closely linked.None of the mutant strains is deficient in recombination, as measured by transformation. The repair of MTC-induced DNA damage in M. radiodurans must be different from that described for Escherichia coli.  相似文献   

19.
β-Peptides and their derivates are usually stable to proteolysis and have an increased half-life compared with α-peptides. Recently, β-aminopeptidases were described as a new enzyme class that enabled the enzymatic degradation and formation of β-peptides. As an alternative to the existing chemical synthesis routes, the aim of the present work was to develop a whole-cell biocatalyst for the synthesis and production of β-peptides using this enzymatic activity. For the optimization of the reaction system we chose the commercially relevant β,α-dipeptide l -carnosine (β-alanine-l -histidine) as model product. We were able to show that different recombinant yeast and bacteria strains, which overexpress a β-peptidase, could be used directly as whole-cell biocatalysts for the synthesis of l -carnosine. By optimizing relevant reaction conditions for the best-performing recombinant Escherichia coli strain, such as pH and substrate concentrations, we obtained high l -carnosine yields of up to 71%. Long-time as well as biocatalyst recycling experiments indicated a high stability of the developed biocatalyst for at least five repeated batches. Application of the recombinant E. coli in a fed-batch process enabled the accumulation of l -carnosine to a concentration of 3.7 g l−1.  相似文献   

20.
The thermoacidophilic Acidianus strain DS80 displays versatility in its energy metabolism and can grow autotrophically and heterotrophically with elemental sulfur (S°), ferric iron (Fe3+) or oxygen (O2) as electron acceptors. Here, we show that autotrophic and heterotrophic growth with S° as the electron acceptor is obligately dependent on hydrogen (H2) as electron donor; organic substrates such as acetate can only serve as a carbon source. In contrast, organic substrates such as acetate can serve as electron donor and carbon source for Fe3+ or O2 grown cells. During growth on S° or Fe3+ with H2 as an electron donor, the amount of CO2 assimilated into biomass decreased when cultures were provided with acetate. The addition of CO2 to cultures decreased the amount of acetate mineralized and assimilated and increased cell production in H2/Fe3+ grown cells but had no effect on H2/S° grown cells. In acetate/Fe3+ grown cells, the presence of H2 decreased the amount of acetate mineralized as CO2 in cultures compared to those without H2. These results indicate that electron acceptor availability constrains the variety of carbon sources used by this strain. Addition of H2 to cultures overcomes this limitation and alters heterotrophic metabolism.  相似文献   

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