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101.
Mingzhang Guo Qi Bao Siyuan Chen Xingtian Cui Wentao Xu Xiaoyun He Yunbo Luo Xiaozhe Qi Kunlun Huang 《World journal of microbiology & biotechnology》2016,32(3):43
Rabbit neutrophils peptide-1 (NP-1) is a type of defensin that possesses a broad spectrum of antimicrobial activity. Chlorella ellipsoidea is a new eukaryotic expression system for exogenously producing NP-1. The NP-1 transgenic C. ellipsoidea can be directly added into feed as antimicrobial agent without any purification procedure for the NP-1 peptide. However, the effects of C. ellipsoidea and NP-1 on the host gut microbiota should be explored before application. In this study, diets containing different concentrations (1.25, 2.5, and 5 %) of C. ellipsoidea and NP-1 transgenic C. ellipsoidea were administered to male Sprague–Dawley rats. Compared with the chow diet control group, none of the experimental groups showed any significant differences in their growth indices, and no histopathological damage was observed. The phylotypes of gut microbiota in the control group, the 5 % C. ellipsoidea diet group and the 5 % NP-1 transgenic C. ellipsoidea diet group were determined by 16S rRNA sequencing. The results showed that both 5 % experimental groups had shifted community memberships of gut microbiota. In particular, the 5 % NP-1 transgenic C. ellipsoidea diet exhibited an increased abundance of most Gram-positive bacterial taxa and a reduced abundance of most Gram-negative bacterial taxa, and it promoted the growth of some lactic acid bacterial genera. Lactic acid bacteria, especially the Bifidobacterium and Lactobacillus, have been widely reported to be benefic effects on the host. Thus NP-1 transgenic C. ellipsoidea is promising feed additive and gut regulator, as it have the potential to increase the abundance of Bifidobacterium and Lactobacillus in gut microbiota of animal. 相似文献
102.
Telmatochromis temporalis is a biparental substrate breeding cichlid that mates in size-assortative monogamy at the southern end of Lake Tanganyika.
In this population, at least a few months before the rainy season, large males (90–110 mm TL) did not pair. However, they
maintained large territories that were defended against conspecific large males and that contained several pairing small males
(50–80 mm). Large males occasionally visited the nests of the small pairs in their territories, and selectively took over
the nests by attacking the owner male. During the takeover, the large males courted the small females in the nests and might
have ejaculated sperm. After the large males left the nests, the small owner males conducted paternal care at the nests. These
behaviour patterns of large males are similar to piracy mating reported in other polygamous fish species. The piracy mating
of large maleT. temporalis seems to be an alternative tactic when large females are not available. 相似文献
103.
Samane Naeeminejad Reza Assaran Darban Sima Beigoli Mohammad Reza Saberi 《Journal of biomolecular structure & dynamics》2017,35(15):3250-3267
The interaction between synthesized heterocyclic benzene sulfonamide compounds, N-(7-benzyl-56-biphenyl-2m-tolyl-7H-pyrrolo[23-d]pyrimidine–4–yl)-benzene sulfonamide (HBS1), N-(7-benzyl-56-biphenyl-2-m-tolyl-7H-pyrrolo[23-d] pyrimidine-4-yl)-4-methyl- benzene sulfonamide (HBS2), and N-(7-benzyl-56-biphenyl-2-m-tolyl-7H-pyrrolo[23-d]pyrimidine-4-yl)-4-chloro-benzene sulfonamide (HBS3) with Hb was studied by fluorescence quenching, zeta potentional, circular dichroism, and molecular modeling techniques. The fluorescence spectroscopy experiments were performed in order to study the conformational changes, possibly due to a discrete reorganization of Trp residues during binding between HBS derivatives and Hb. The variation of the KSV value suggested that hydrophobic and electrostatic interactions were the predominant intermolecular forces stabilizing the complex. The KSV1 ans KSV2 values of HBS derivatives with Hb are .6 × 1013 and 3 × 1013 M?1 for Hb–HBS1, 1 × 1013 and 4 × 1013 M?1 for Hb–HBS2, .9 × 1013, and 6 × 1013 M?1 for Hb–HBS3, respectively. The molecular distances between Hb and HBS derivatives in binary and ternary systems were estimated according to Förster’s theory of dipole–dipole non-radiation energy transfer. The quantitative analysis data of circular dichroism spectra demonstrated that the binding of the three HBS derivatives to Hb induced conformational changes in Hb. Changes in the zeta potential of the Hb–HBS derivatives complexes demonstrated a hydrophobic adsorption of the anionic ligand onto the surface of Hb as well as both electrostatic and hydrophobic adsorption in the case of the complex. The modeling data thus confirmed the experimental results. This study is expected to provide important insight into the interaction of Hb with three HBS derivatives to use in various toxicological and therapeutic processes. 相似文献
104.
105.
Chen L Hainrichson M Bourdetsky D Mor A Yaron S Baasov T 《Bioorganic & medicinal chemistry》2008,16(19):8940-8951
A new pseudo-disaccharide NB23 with a 3',4'-methylidene protection was designed and its properties were evaluated in comparison to other two structurally related pseudo-disaccharides. The basicity of the 2'-amine was found to be well correlated to acute toxicity data in mice: the increase in the basicity is associated with the toxicity increase. Based on these data, a new pseudo-trisaccharide NB45 was constructed. NB45 exhibited significant antibacterial activity while at the same time retained low acute toxicity. 相似文献
106.
Environmental and social factors have important effects on aggressive behaviors. We examined the effect of reproductive experience on aggression in a biparental species of mouse, Peromyscus californicus. Estrogens are important in mediating aggressive behavior so we also examined estrogen receptor expression and c-fos for insights into possible mechanisms of regulation. Parental males were significantly more aggressive than virgin males, but no significant differences in estrogen receptor alpha or beta expression were detected. Patterns of c-fos following aggression tests suggested possible parallels with maternal aggression. Parental males had more c-fos positive cells in the medial amygdala, and medial preoptic area relative to virgin males. The medial preoptic area is generally considered to be relatively less important for male-male aggression in rodents, but is known to have increased activity in the context of maternal aggression. We also demonstrated through habituation-dishabituation tests that parental males show exaggerated investigation responses to chemical cues from a male intruder, suggesting that heightened sensory responses may contribute to increased parental aggression. These data suggest that, in biparental species, reproductive experience leads to the onset of paternal aggression that may be analogous to maternal aggression. 相似文献
107.
Sampath Amutha Krishnan Kathiravan Sima Singer Liana Jashi Ilan Shomer Benjamin Steinitz Victor Gaba 《In vitro cellular & developmental biology. Plant》2009,45(6):758-768
Regeneration of new shoots in plant tissue culture is often associated with appearance of abnormally shaped leaves. We used
the adventitious shoot regeneration response induced by decapitation (removal of all preformed shoot apical meristems, leaving
a single cotyledon) of greenhouse-grown cotyledon-stage seedlings to test the hypothesis that such abnormal leaf formation
is a normal regeneration progression following wounding and is not conditioned by tissue culture. To understand why shoot
regeneration starts with defective organogenesis, the regeneration response was characterized by morphology and scanning electron
and light microscopy in decapitated cotyledon-stage Cucurbita pepo seedlings. Several leaf primordia were observed to regenerate prior to differentiation of a de novo shoot apical meristem from dividing cells on the wound surface. Early regenerating primordia have a greatly distorted structure
with dramatically altered dorsoventrality. Aberrant leaf morphogenesis in C. pepo gradually disappears as leaves eventually originate from a de novo adventitious shoot apical meristem, recovering normal phyllotaxis. Similarly, following comparable decapitation of seedlings
from a number of families (Chenopodiaceae, Compositae, Convolvulaceae, Cucurbitaceae, Cruciferae, Fabaceae, Malvaceae, Papaveraceae,
and Solanaceae) of several dicotyledonous clades (Ranunculales, Caryophyllales, Asterids, and Rosids), stems are regenerated
bearing abnormal leaves; the normal leaf shape is gradually recovered. Some of the transient leaf developmental defects observed
are similar to responses to mutations in leaf shape or shoot apical meristem function. Many species temporarily express this
leaf development pathway, which is manifest in exceptional circumstances such as during recovery from excision of all preformed
shoot meristems of a seedling. 相似文献
108.
从黑果枸杞中分离得到18株黑果枸杞内生真菌,其中从棘刺分离得到3株,从根部分离得到10株,从茎部分离得到5株。对其内生真菌使用固体发酵技术放大培养后,使用固相微萃取材料对黑果枸杞内生真菌挥发性成分进行固定吸附后,经过气相色谱-质谱联用仪(GC-MS)技术解吸附分析。结果表明,4株黑果枸杞植物内生真菌(KLBMPLR001、KLBMPLR004、KLBMPLR013和KLBMPLR018)中的挥发性成分多属于有机酸、芳香烃、酯类及其少量醇类、酚类和倍半萜化合物。4株菌株有机酸百分含量分别为48.69%、51.26%、47.75%和17.78%;芳香烃类百分含量分别为6.79%、19.23%、8.65%和5.75%;酯类百分含量分别为17.18%、7.37%、5.45%和7.95%。 相似文献
109.
Poulton CJ Schot R Kia SK Jones M Verheijen FW Venselaar H de Wit MC de Graaff E Bertoli-Avella AM Mancini GM 《American journal of human genetics》2011,(2):519-276
We describe a syndrome of primary microcephaly with simplified gyral pattern in combination with severe infantile epileptic encephalopathy and early-onset permanent diabetes in two unrelated consanguineous families with at least three affected children. Linkage analysis revealed a region on chromosome 18 with a significant LOD score of 4.3. In this area, two homozygous nonconserved missense mutations in immediate early response 3 interacting protein 1 (IER3IP1) were found in patients from both families. IER3IP1 is highly expressed in the fetal brain cortex and fetal pancreas and is thought to be involved in endoplasmic reticulum stress response. We reported one of these families previously in a paper on Wolcott-Rallison syndrome (WRS). WRS is characterized by increased apoptotic cell death as part of an uncontrolled unfolded protein response. Increased apoptosis has been shown to be a cause of microcephaly in animal models. An autopsy specimen from one patient showed increased apoptosis in the cerebral cortex and pancreas beta cells, implicating premature cell death as the pathogenetic mechanism. Both patient fibroblasts and control fibroblasts treated with siRNA specific for IER3IP1 showed an increased susceptibility to apoptotic cell death under stress conditions in comparison to controls. This directly implicates IER3IP1 in the regulation of cell survival. Identification of IER3IP1 mutations sheds light on the mechanisms of brain development and on the pathogenesis of infantile epilepsy and early-onset permanent diabetes. 相似文献
110.