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71.
RS Mehta A Rodriguez M Chico I Guadalupe N Broncano C Sandoval F Tupiza E Mitre PJ Cooper 《PLoS neglected tropical diseases》2012,6(7):e1753
Background
Children of mothers infected with soil-transmitted helminths (STH) may have an increased susceptibility to STH infection.Methods and Findings
We did a case-control study nested in a birth cohort in Ecuador. Data from 1,004 children aged 7 months to 3 years were analyzed. Cases were defined as children with Ascaris lumbricoides and/or Trichuris trichiura, controls without. Exposure was defined as maternal infection with A. lumbricoides and/or T. trichiura, detected during the third trimester of pregnancy. The analysis was restricted to households with a documented infection to control for infection risk. Children of mothers with STH infections had a greater risk of infection compared to children of uninfected mothers (adjusted OR 2.61, 95% CI: 1.88–3.63, p<0.001). This effect was particularly strong in children of mothers with both STH infections (adjusted OR: 5.91, 95% CI: 3.55–9.81, p<0.001). Newborns of infected mothers had greater levels of plasma IL-10 than those of uninfected mothers (p = 0.033), and there was evidence that cord blood IL-10 was increased among newborns who became infected later in childhood (p = 0.060).Conclusion
Our data suggest that maternal STH infections increase susceptibility to infection during early childhood, an effect that was associated with elevated IL-10 in cord plasma. 相似文献72.
Bo Xiong Vafa Bayat Manish Jaiswal Ke Zhang Hector Sandoval Wu-Lin Charng Tongchao Li Gabriela David Lita Duraine Yong-Qi Lin G. Gregory Neely Shinya Yamamoto Hugo J. Bellen 《PLoS biology》2012,10(12)
Rhodopsins (Rhs) are light sensors, and Rh1 is the major Rh in the Drosophila photoreceptor rhabdomere membrane. Upon photoactivation, a fraction of Rh1 is internalized and degraded, but it remains unclear how the rhabdomeric Rh1 pool is replenished and what molecular players are involved. Here, we show that Crag, a DENN protein, is a guanine nucleotide exchange factor for Rab11 that is required for the homeostasis of Rh1 upon light exposure. The absence of Crag causes a light-induced accumulation of cytoplasmic Rh1, and loss of Crag or Rab11 leads to a similar photoreceptor degeneration in adult flies. Furthermore, the defects associated with loss of Crag can be partially rescued with a constitutive active form of Rab11. We propose that upon light stimulation, Crag is required for trafficking of Rh from the trans-Golgi network to rhabdomere membranes via a Rab11-dependent vesicular transport. 相似文献
73.
Eigenbrot C Ultsch M Lipari MT Moran P Lin SJ Ganesan R Quan C Tom J Sandoval W van Lookeren Campagne M Kirchhofer D 《Structure (London, England : 1993)》2012,20(6):1040-1050
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74.
Justin M. Scheer Wendy Sandoval J. Michael Elliott Lily Shao Elizabeth Luis Sock-Cheng Lewin-Koh Gabriele Schaefer Richard Vandlen 《PloS one》2012,7(12)
The structure of the Fab region of antibodies is critical to their function. By introducing single cysteine substitutions into various positions of the heavy and light chains of the Fab region of trastuzumab, a potent antagonist of HER2, and using thiol chemistry to link the different Fabs together, we produced a variety of monospecific F(ab′)2-like molecules with activities spanning from activation to inhibition of breast tumor cell growth. These isomers (or bis-Fabs) of trastuzumab, with varying relative spatial arrangements between the Fv-regions, were able to either promote or inhibit cell-signaling activities through the PI3K/AKT and MAPK pathways. A quantitative phosphorylation mapping of HER2 indicated that the agonistic isomers produced a distinct phosphorylation pattern associated with activation. This study suggests that antibody geometric isomers, found both in nature and during synthetic antibody development, can have profoundly different biological activities independent of their affinities for their target molecules. 相似文献
75.
76.
Carlos E. Aragón Maritza Escalona Iris Capote Danilo Pina Inaudis Cejas Roberto Rodriguez Maria Jesus Cañal Jorge Sandoval Sophe Roels Pierre Debergh Justo Gonzalez-Olmedo 《In vitro cellular & developmental biology. Plant》2005,41(4):550-554
Summary The photosynthetic capacity changes and the main enzymatic systems related to carbon metabolism were investigated during the
in vitro culture of plantain shoots (Musa AAB cv. CEMSA 3/4) in temporary immersion bioreactors (TIB) and their subsequent acclimatization.
The maximal rate of photosynthesis (Pn), transpiration, and the activity of the carbon metabolism enzymes phosphoenolpyruvate
carboxylase (PEPC), acid invertase (AI), pyruvate kinase (PK) and sucrose phosphate synthase (SPS) were measured every 7 d
during the 21 d of elongation in TIB, and the following 42 d of acclimatization. Sucrose content in the liquid medium and
in the leaves was also determined. The most significant changes in plant growth were observed during acclimatization. During
the in vitro stage photosynthesis was limited (4–6 μmol CO2m−2s−1); the photosynthetic rate however increases rapidly and significantly as soon as in vitro culture is over during acclimatization. PEPC activity increased during the whole evaluation period. The highest levels were
achieved around days 42 and 56. PK and SPS activities were optimal during the first weeks in acclimatization (28–35 d), while
AI increased at the beginning of the elongation phase (7 d), and later at the end of the acclimatization (49–63 d). The relationships
between morphological parameters, photosynthetic capacity of the plantlets and the carbon metabolism enzymes during both phases
of the culture are discussed. 相似文献
77.
78.
Strategy for Cloning Large Gene Assemblages as Illustrated Using the Phenylacetate and Polyhydroxyalkanoate Gene Clusters
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Beln García Elías R. Olivera ngel Sandoval Elsa Arias-Barrau Sagrario Arias Germn Naharro Jos M. Luengo 《Applied microbiology》2004,70(8):5019-5025
We report an easy procedure for isolating chromosome-clustered genes. By following this methodology, the entire set of genes belonging to the phenylacetic acid (PhAc; 18-kb) pathway as well as those required for the synthesis and mobilization of different polyhydroxyalkanoates (PHAs; 6.4 kb) in Pseudomonas putida U were recovered directly from the bacterial chromosome and cloned into a plasmid for the first time. The transformation of different bacteria with these genetic constructions conferred on them the ability to either degrade PhAc or synthesize bioplastics (PHAs). 相似文献
79.
80.
Alfredo Téllez-Valencia Ada A. Sandoval Mario Pedraza-Reyes 《Current microbiology》2003,46(4):0307-0310
The modular endocellulase Cel9 of the bicistronic operon cel9-cel48 of Myxobacter sp. AL-1 shares not only amino acid sequence similarity but also biochemical properties similar to those of Thermobifida fusca endo/exocellulase E4. Amino acid alignments of a T. fusca E4 cellulase subfamily of family 9 cellulases revealed that Asp446 of Myxobacter sp. AL-1 Cel9, a putatively noncatalytic residue, is highly conserved in one of the catalytic domains of this subfamily.
Directed mutagenesis of residue aspartate (Asp446) to alanine generated a Cel9 mutant that lost more than 99% of its activity, suggesting that Asp446 plays an essential structural role in Cel9 during cellulose degradation. Owing to its high degree of conservation and essential
role, we propose that Asp446 of Myxobacter sp. AL-1 Cel9 is a good landmark that distinguishes members of the E4 subfamily of family 9 cellulases.
Received: 4 May 2002 / Accepted: 5 July 2002 相似文献