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41.
42.
The economics surrounding five algae-to-fuels process scenarios were examined. The different processes modeled were as follows: an open pond producing either triacylglycerides (TAG) or free fatty acid methyl ester (FAME), a solar-lit photobioreactor producing either FAME or free fatty acids (FFA), and a light emitting diode irradiated (LED-lighted) photobioreactor producing TAG. These processes were chosen to represent both classical and esoteric approaches presented in the open literature. Viable (or suggested) processing techniques to liberate and purify (and convert) the microalgal triacylglycerides were then modeled to accompany each growth option. The investment and cost per kg of fuel or fuel precursor for each process was determined. The open pond produced TAG at ~$7.50/kg, while the process using the LED-lit photobioreactor produced TAG at ~$33/kg. The scenario containing the solar-lit photobioreactor produced FAME at ~$25/kg, while the open pond produced FAME at ~$4/kg. The scenario containing the solar-lit photobioreactor produced FFA at ~$29/kg. The open pond scenarios appear to be closest to the $1/kg pricepoint at this time, and thus are the most viable economic options. Future technological advancements that reduce the cost of bioreactor vessels, LED lighting, and solvent recovery, may reduce the oil production costs of these scenarios to a more attractive level.  相似文献   
43.
Euphorbia pulcherrima, an ornamental plant, exhibits severe systemic viral infection. It grows vegetatively during summer and is dormant in winter. During the dormant period the buds on healthy stem cuttings remained dormant or rarely formed cyathia while the buds on virus-infected stem cuttings grew into leafy shoots and never became dormant. Quantitative estimation has revealed that breaking of bud dormancy in virus-infected stem cuttings may be regulated by markedly higher GA-like activity in them throughout the period than in their corresponding healthy stem cuttings.  相似文献   
44.
The genetic diversity of 31 identified strains of Lactococcus lactis ssp. lactis isolated from different dairy and non-dairy sources were investigated at gene level using multilocus sequence analysis (MLSA) and PCR-RFLP based on the differences in four selected partial protein coding gene sequences: araT, encoding aromatic amino acid-specific aminotransferase; dtpT, encoding di/tri peptide transporter; yueF, encoding non-proteolytic protein, peptidase, M16 family; and pdhA, encoding pyruvate dehydrogenase E1 component α-subunit. A set of seven test strains from different isolation sources and one reference strain, L. lactis ssp. lactis NCDC 094, were analyzed by MLSA. The strains showed distinct diversity among themselves and exhibited a greater percent similarity with reference strains L. lactis ssp. lactis CV56 (CP002365.1), IL1403 (AE005176.1), and KF147 (CP001834.1) in comparison with L. lactis ssp. cremoris NZ9000 (CP002094.1), MG1363 (AM406671.1), and SK11 (CP00425.1). The MLSA revealed one distinct genomic lineage within strains exclusively of L. lactis ssp. lactis. This analysis also revealed no source-wise genetic relationship in the test strains analyzed. Further, PCR-RFLP of araT, dtpT, yueF and pdhA also characterized the single genomic lineage exclusively of L. lactis ssp. lactis within a total of 24 test strains.  相似文献   
45.
46.

Rationale

Obliterative bronchiolitis (OB) is a significant cause of morbidity and mortality after lung transplant and hematopoietic cell transplant. Mesenchymal stromal cells (MSCs) have been shown to possess immunomodulatory properties in chronic inflammatory disease.

Objective

Administration of MSCs was evaluated for the ability to ameliorate OB in mice using our established allogeneic bone marrow transplant (BMT) model.

Methods

Mice were lethally conditioned and received allogeneic bone marrow without (BM) or with spleen cells (BMS), as a source of OB-causing T-cells. Cell therapy was started at 2 weeks post-transplant, or delayed to 4 weeks when mice developed airway injury, defined as increased airway resistance measured by pulmonary function test (PFT). BM-derived MSC or control cells [mouse pulmonary vein endothelial cells (PVECs) or lung fibroblasts (LFs)] were administered. Route of administration [intratracheally (IT) and IV] and frequency (every 1, 2 or 3 weeks) were compared. Mice were evaluated at 3 months post-BMT.

Measurements and Main Results

No ectopic tissue formation was identified in any mice. When compared to BMS mice receiving control cells or no cells, those receiving MSCs showed improved resistance, compliance and inspiratory capacity. Interim PFT analysis showed no difference in route of administration. Improvements in PFTs were found regardless of dose frequency; but once per week worked best even when administration began late. Mice given MSC also had decreased peribronchiolar inflammation, lower levels of hydroxyproline (collagen) and higher frequencies of macrophages staining for the alternatively activated macrophage (AAM) marker CD206.

Conclusions

These results warrant study of MSCs as a potential management option for OB in lung transplant and BMT recipients.  相似文献   
47.
Enterohaemorrhagic Escherichia coli (EHEC) colonizes the intestine and causes bloody diarrhoea and kidney failure by producing Shiga toxin. Upon binding intestinal cells, EHEC triggers a change in host cell shape, generating actin ‘pedestals’ beneath bound bacteria. To investigate the importance of pedestal formation to disease, we infected genetically engineered mice incapable of supporting pedestal formation by an EHEC‐like mouse pathogen, or wild type mice with a mutant of that pathogen incapable of generating pedestals. We found that pedestal formation promotes attachment of bacteria to the intestinal mucosa and vastly increases the severity of Shiga toxin‐mediated disease.  相似文献   
48.
Our previous studies demonstrated that fluorescent early endocytic vesicles prepared from rat liver after injection of Texas red asialoorosomucoid contain asialoglycoprotein and its receptor and move and undergo fission along microtubules using kinesin I and KIFC2, with Rab4 regulating KIFC2 activity (J. Cell Sci. 116, 2749, 2003). In the current study, procedures to prepare fluorescent late endocytic vesicles were devised. In addition, flow cytometry was utilized to prepare highly purified fluorescent endocytic vesicles, permitting validation of microscopy-based experiments as well as direct biochemical analysis. These studies revealed that late vesicles bound to and moved along microtubules, but in contrast to early vesicles, did not undergo fission. As compared with early vesicles, late vesicles had reduced association with receptor, Rab4, and kinesin I but were highly associated with dynein, Rab7, dynactin, and KIF3A. Dynein and KIF3A antibodies inhibited late vesicle motility, whereas kinesin I and KIFC2 antibodies had no effect. Dynamitin antibodies prevented the association of late vesicles with microtubules. These results indicate that acquisition and exchange of specific motor and regulatory proteins characterizes and may regulate the transition of early to late endocytic vesicles. Flow cytometric purification should ultimately facilitate detailed proteomic analysis and mapping of endocytic vesicle-associated proteins.  相似文献   
49.
Recent genome‐wide association studies (GWAS) in Asian Indians reported strong associations of variants near melanocortin‐4 receptor (MC4R) and MLX interacting protein‐like (MLXIPL) genes with insulin resistance and several obesity‐related quantitative traits (QTs). Here, we evaluated the association of two variants (rs12970134 and rs4450508) near MC4R and a nonsynonymous (Gln241His) variant (rs3812316) in MLXIPL gene with type 2 diabetes (T2D) and obesity‐related QTs in our case–control cohort (n = 1,528; 745 T2D cases and 783 controls) from a Sikh population from North India. We have successfully replicated the association of MC4R (rs12970134) with BMI (P = 0.0005), total weight (WT) (P = 0.001), and waist circumference (WC) (P = 0.001). These associations remained significant after controlling for multiple testing by applying Bonferroni's correction. However, our data did not confirm the association of rs3812316 in the MLXIPL gene with triglyceride (TG) levels. These observations demonstrate that the genetic variation in MC4R locus can have a moderate contribution in the regional fat deposition and development of central obesity in Asian Indians.  相似文献   
50.
The yeast has important role in fermentation of wine grapes and wine quality. The fermentation of wine grapes affect by efficiency of particular yeast strain, sugar content, pH, available temperature, etc. To evaluate the efficiency of yeast strains (Premier Cuvee, RS-1, RS-2, RS-3 and natural), present study was conducted on two wine grape varieties viz.; Sauvignon Blanc (White) and Cabernet Sauvignon (Red). Efficiency of yeast strains was evaluated in terms of conversion rate of sugar into alcohol. As per recorded data, strain RS-3 (Pichia kudriavzevii) was found more efficient than other strains in fermentation of Cabernet Sauvignon with efficiency of 84.4 per cent but in case of Sauvignon Blanc, the commercial culture Premier Cuevee was found superior over RS-3. The quality parameters of young wines of both the varieties were also affected by the used strains. Considering the efficiency and impact on various parameters of wines, local strain, i.e., RS-3 was found at par with commercial culture (Premier Cuvee). The RS-3 strain has potential to produce quality wines. However, studies on effects of RS-3 strain on some specific quality parameters of wines like varietal aroma compounds, flavours etc. are needed.  相似文献   
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