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151.
152.
Delta-like 1 (Dlk1, also known as fetal antigen-1, FA1) is a member of Notch/Delta family that inhibits adipocyte and osteoblast differentiation; however, its role in chondrogenesis is still not clear. Thus, we overexpressed Dlk1/FA1 in mouse embryonic ATDC5 cells and tested its effects on chondrogenic differentiation. Dlk1/FA1 inhibited insulin-induced chondrogenic differentiation as evidenced by reduction of cartilage nodule formation and gene expression of aggrecan, collagen Type II and X. Similar effects were obtained either by using Dlk1/FA1-conditioned medium or by addition of a purified, secreted, form of Dlk1 (FA1) directly to the induction medium. The inhibitory effects of Dlk1/FA1 were dose-dependent and occurred irrespective of the chondrogenic differentiation stage: proliferation, differentiation, maturation, or hypertrophic conversion. Overexpression or addition of the Dlk1/FA1 protein to the medium strongly inhibited the activation of Akt, but not the ERK1/2, or p38 MAPK pathways, and the inhibition of Akt by Dlk1/FA1 was mediated through PI3K activation. Interestingly, inhibition of fibronectin expression by siRNA rescued the Dlk1/FA1-mediated inhibition of Akt, suggesting interaction of Dlk1/FA1 and fibronectin in chondrogenic cells. Our results identify Dlk1/FA1 as a novel regulator of chondrogenesis and suggest Dlk1/FA1 acts as an inhibitor of the PI3K/Akt pathways that leads to its inhibitory effects on chondrogenesis.  相似文献   
153.
Maedi-Visna is an important slow viral disease of sheep leading to progressive pneumonia, encephalitis and mastitis. Udder is one of the organs affected by MVV. Despite the fact that in Iran Maedi-Visna is known since 2000, to the authors’ knowledge correlation of subclinical mastitis and infection with MVV has not been assayed. In this study 50 milk samples from 10 flocks in East Azerbaijan Province of Iran were tested. None of the animals exhibited any clinical signs of the disease. Forty samples were collected from CMT positive ewes and ten were taken from CMT negative ewes. Milk samples were analyzed using PCR targeting gag sequence. Presence of provirus DNA was detected in one sample from CMT negative and seven samples from CMT positive ewes. These data demonstrate that 16.5 % of sheep with subclinical mastitis were infected to MVV. Thus this virus can be considered one of the main pathogenic agents of mastitis and can be dramatically transmitted to lambs by milk.  相似文献   
154.
Five species (14 ecotypes) belonging to three subgenera of ornamental-medicinal Iranian Fritillaria plant were chromosomally and karyotypically assessed, using squash technique and 1 % (w/v) aceto-orcein stain. All species were diploid (2n = 2x = 24) having mean chromosome length of 16.8 μm (14.2–18.6 μm). The satellites varied in number (1–4 pairs) and in size (1.27–3.01 μm): mostly locating on long arms. Four chromosome types (“m”, “sm”, “st”, “T”) formed 11 different karyotypic formulas: the latter is being reported for the first time in some ecotypes in either S1 or S4. Nine chromosomal parameters were calculated. ANOVA verified intra- and inter-specific chromosomal variation in examined Iranian Fritillaria species. Twelve different methods were used to assess the degree of karyotype asymmetry. Among those, one qualitative (Stebbins classification) and seven quantitative (TF %, CVTL, DI, AsK %, A2, Rec, CG %) parameters verified that S2 and S5 species were recognized as having the most asymmetrical and symmetrical karyotypes, respectively.  相似文献   
155.

Background

According to WHO estimates, 35% of global measles deaths in 2011 occurred in India. In 2013, India committed to a goal of measles elimination by 2020. Laboratory supported case based measles surveillance is an essential component of measles elimination strategies. Results from a case-based measles surveillance system in Pune district (November 2009 through December 2011) are reported here with wider implications for measles elimination efforts in India.

Methods

Standard protocols were followed for case identification, investigation and classification. Suspected measles cases were confirmed through serology (IgM) or epidemiological linkage or clinical presentation. Data regarding age, sex, vaccination status were collected and annualized incidence rates for measles and rubella cases calculated.

Results

Of the 1011 suspected measles cases reported to the surveillance system, 76% were confirmed measles, 6% were confirmed rubella, and 17% were non-measles, non-rubella cases. Of the confirmed measles cases, 95% were less than 15 years of age. Annual measles incidence rate was more than 250 per million persons and nearly half were associated with outbreaks. Thirty-nine per cent of the confirmed measles cases were vaccinated with one dose of measles vaccine (MCV1).

Conclusion

Surveillance demonstrated high measles incidence and frequent outbreaks in Pune where MCV1 coverage in infants was above 90%. Results indicate that even high coverage with a single dose of measles vaccine was insufficient to provide population protection and prevent measles outbreaks. An effective measles and rubella surveillance system provides essential information to plan, implement and evaluate measles immunization strategies and monitor progress towards measles elimination.  相似文献   
156.
Valerenic acid (VA) is a pharmacologically-active sesquiterpene found in valerian (Valeriana officinalis L., Valerianaceae) roots and rhizomes. The plant produces only small amounts of this metabolite naturally. So, induction of hairy roots as well as elicitation can be useful to increase its commercial production. In this study, Wild-type strain ‘A13’ of Agrobacterium rhizogenes was used to induce hairy roots in valerian. The influence of three different elicitors including Fusarium graminearum extract (FE), methyl jasmonate (MJ) and salicylic acid (SA) on VA production in the selected hairy root line ‘LeVa-C4’ was also investigated. The 23-day-old cultures were treated with different concentrations of the elicitors at exposure time of 3 and 7 days. FE (1%) and MJ (100 µM L?1) highly promoted VA production at 7 days after elicitation, to a level of 12.31- and 6-fold higher than that of non-elicited controls, respectively, and FE did not exert any negative effects on biomass yield of hairy root. SA did not significantly increase the production of VA. This is the first time study to assess the elicitation of hairy root cultures to promote VA biosynthesis in valerian and the resulting experiments demonstrated that F. graminearum extract and MJ were indeed a potent inducer of VA biosynthesis.  相似文献   
157.
Neurochemical Research - Diabetic neuropathy is one of the most common complications of diabetes mellitus. Excess glutamate release and oxidative stress are hypothesized to be involved in the...  相似文献   
158.
159.
Probiotics and Antimicrobial Proteins - This work evaluated the effect of dietary supplementation of probiotic, Pediococcus acidilactici and nucleotide (combined or individual) on reproductive...  相似文献   
160.
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