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941.
Haploinsufficiency of the human 5q35 region spanning the NSD1 gene results in a rare genomic disorder known as Sotos syndrome (Sotos), with patients displaying a variety of clinical features, including pre- and postnatal overgrowth, intellectual disability, and urinary/renal abnormalities. We used chromosome engineering to generate a segmental monosomy, i.e., mice carrying a heterozygous 1.5-Mb deletion of 36 genes on mouse chromosome 13 (4732471D19Rik-B4galt7), syntenic with 5q35.2?Cq35.3 in humans (Df(13)Ms2Dja +/? mice). Surprisingly Df(13)Ms2Dja +/? mice were significantly smaller for their gestational age and also showed decreased postnatal growth, in contrast to Sotos patients. Df(13)Ms2Dja +/? mice did, however, display deficits in long-term memory retention and dilation of the pelvicalyceal system, which in part may model the learning difficulties and renal abnormalities observed in Sotos patients. Thus, haploinsufficiency of genes within the mouse 4732471D19Rik?CB4galt7 deletion interval play important roles in growth, memory retention, and the development of the renal pelvicalyceal system.  相似文献   
942.
To investigate the immunomodulatory effects of Bacillus subtilis (B. subtilis) (natto) B4 spores on murine macrophage, RAW 264.7 cells were cultured alone or with B subtilis (natto) B4 spores at 37°C for 12 hrs, then both cells and culture supernatants were collected for analyses. Exposure of RAW 264.7 cells to B. subtilis (natto) B4 spores had no significant effects on macrophage viability and amounts of extracellular lactate dehydrogenase (LDH). However, it remarkably increased the activities of acid phosphatase (ACP), lactate dehydrogenase (LDH) and inducible nitric oxide synthase (iNOS) in cells and the amounts of nitric oxide (NO) and cytokines (tumor necrosis factor‐alpha, interferon‐gamma, interleukin [IL]‐1 beta, IL‐6, IL‐12, IL‐10 and macrophage inflammatory protein‐2) in culture supernatants. These results demonstrate that B. subtilis (natto) B4 spores are harmless to murine macrophages and can stimulate their activation through up‐regulation of ACP and LDH activities and enhance their immune function by increasing iNOS activity and stimulating NO and cytokine production. The above findings suggest that B. subtilis (natto) B4 spores have immunomodulatory effects on macrophages.  相似文献   
943.
944.
Rashid MU  Weintraub A  Nord CE 《Anaerobe》2012,18(2):249-253
The human normal microflora is relatively stable at each ecological habitat under normal circumstances and acts as a barrier against colonization by potentially pathogenic microorganisms and against overgrowth of already present opportunistic microorganisms. Administration of antimicrobial agents causes disturbances in the ecological balance between the host and the normal microflora. The risk of emergence and spread of resistant strains between patients and dissemination of resistant determinants between microorganisms is reduced if colonization resistance is not disturbed by antimicrobial agents. In this article, the potential ecological effects of administration of new antimicrobial agents on the intestinal and oropharyngeal microflora are summarized. The review is based on clinical studies published during the past 10 years.  相似文献   
945.

Background and aims

Phosphorus (P) is a commonly limiting nutrient for plant growth in natural environments. Many legumes capable of N2-fixation require more P than non-legumes do. Some legume crops can use sparingly soluble forms of P such as iron phosphate much better than other species, but reports on the ability of woody legumes to access iron phosphate are rare.

Methods

Plants of four Acacia species (Acacia stipuligera F. Muell., A. ancistrocarpa Maiden & Blakely, A. stellaticeps Kodela, Tindale & D. Keith and A. robeorum Maslin), native to the Great Sandy Desert in north-western Australia, were grown in a glasshouse in river sand with different levels of iron phosphate, between 0 and 16?μg P g?1 sand. Plant growth, tissue P concentrations, and pH and carboxylates in the rhizosphere were measured.

Results

Growth of A. stipuligera and A. ancistrocarpa was not responsive to increased P supply; in contrast, A. stellaticeps and A. robeorum produced significantly more root and shoot dry mass at 8 and 16?μg P g?1 sand than at 0?μg P g?1 sand; differences in root mass ratio were significant between species but not between P treatments. A. robeorum was the only species colonised by mycorrhizal fungi, and the colonisation percentage decreased with increasing P supply. In all species, P-uptake rates and tissue P concentrations were significantly higher at greater P supply. Rhizosphere pH and the amount of carboxylates in the rhizosphere decreased with increasing P supply.

Conclusions

Net P uptake increased with increasing P supply, showing that the present Acacia species can access P from iron phosphate. However, due to their inherently slow growth rate, enhanced P supply did not increase growth of two of the four studied species. The ability of the Acacia species to access P from iron phosphate is presumably related with carboxylate exudation and rhizosphere acidification.  相似文献   
946.
947.
The wide knowledge gaps in invasion biology research that exist in the developing world are crucial impediments to the scientific management and global policymaking on biological invasions. In an effort to fill such knowledge gaps, we present here an inventory of the alien flora of India, based on systematic reviews and rigorous analyses of research studies (ca. 190) published over the last 120 years (1890–2010 AD), and updated with field records of the last two decades. Currently, the inventory comprises of 1,599 species, belonging to 842 genera in 161 families, and constitutes 8.5% of the total Indian vascular flora. The three most species-rich families are Asteraceae (134 spp.), Papilionaceae (114 spp.) and Poaceae (106 spp.), and the three largest genera are Eucalyptus (25 spp.), Ipomoea (22 spp.), and Senna (21 spp.). The majority of these species (812) have no report of escaping from cultivation. Of the remaining subset of 787 species, which have either escaped from intentional cultivation, or spread after unintentional introduction, casuals are represented by 57 spp., casual/naturalised by 114 spp., naturalised by 257 spp., naturalised/invasive by 134 spp., and invasive by 225 spp. Biogeographically, more than one-third (35%) of the alien flora in India has its native ranges in South America, followed by Asia (21%), Africa (20%), Europe (11%), Australia (8%), North America (4%); and cryptogenic (1%). The inventory is expected to serve as the scientific baseline on plant invasions in India, with implications for conservation of global biodiversity.  相似文献   
948.
949.
Germline mutations of the LKB1 gene lead to Peutz-Jeghers syndrome (PJS), which is associated with a predisposition to gastrointestinal polyposis and cancer. In this study we tested for germline mutations of LKB1 in 11 patients with PJS from nine families and analyzed the expression patterns of the LKB1 and cyclo-oxygenase-2 (COX-2) proteins in 28 Peutz-Jeghers polyps (PJPs) and five carcinomas from these patients by immunohistochemical (IHC) analysis. In eight of those families we identified seven different mutations, which consisted of two splice site mutations, two nonsense mutations, one small in-frame deletion, one frame-shift mutation, and one silent mutation. Immunostaining revealed nuclear and cytoplasmic expression of LKB1 protein in 23 PJPs and five carcinomas, nuclear expression alone in one PJP, and loss of LKB1 protein expression in four PJPs, indicating a heterogeneous LKB1 expression pattern in PJPs. Overexpression of COX-2 was detected in 23 (82%) of 28 PJPs and in all carcinomas. Despite heterogeneity in staining of LKB1 among individuals and even among samples from the same individual, we found statistically significant correlations in staining of LKB1 relative to COX-2. These results suggest that COX-2 plays a role in tumorigenesis in PJS and may therefore be considered as a potential target for PJS chemoprevention.  相似文献   
950.
Osman  Rashid H.  Liu  Long  Xia  Lili  Zhao  Xing  Wang  Qianqian  Sun  Xiaoxian  Zhang  Yihui  Yang  Biao  Zheng  Yun  Gong  Daoqing  Geng  Tuoyu 《Molecular and cellular biochemistry》2016,415(1-2):103-109

Global prevalence of non-alcoholic fatty liver disease (NAFLD) constitutes a threat to human health. Goose is a unique model of NAFLD for discovering therapeutic targets as its liver can develop severe steatosis without overt injury. Fatty acid desaturase (Fads) is a potential therapeutic target as Fads expression and mutations are associated with liver fat. Here, we hypothesized that Fads was promoted to provide a protection for goose fatty liver. To test this, goose Fads1 and Fads2 were sequenced. Fads1/2/6 expression was determined in goose liver and primary hepatocytes by quantitative PCR. Liver fatty acid composition was also analyzed by gas chromatography. Data indicated that hepatic Fads1/2/6 expression was gradually increased with the time of overfeeding. In contrast, trans-C18:1n9 fatty acid (Fads inhibitor) was reduced. However, enhanced Fads capacity for long-chain polyunsaturated fatty acid (LC-PUFA) synthesis was not sufficient to compensate for the depleted LC-PUFAs in goose fatty liver. Moreover, cell studies showed that Fads1/2/6 expression was regulated by fatty liver-associated factors. Together, these findings suggest Fads1/2 as protective components are promoted to meet instant need for LC-PUFAs in goose fatty liver, and we propose this is required for severe hepatic steatosis without liver injury.

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