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91.
Acosta-Jamett G Astorga-Arancibia F Cunningham AA 《Journal of wildlife diseases》2010,46(4):1204-1213
We immobilized individuals of two species of free-ranging South American foxes, including 28 chilla foxes (Pseudalopex griseus; 13 males and 15 females) and five culpeo foxes (Pseudalopex culpaeus; four males and one female). Animals were trapped and chemically immobilized with ketamine and medetominide (K-M), ketamine and xylazine (K-X), or tiletamine-zolazepam (Z). Heart and respiratory rates, hemoglobin oxygen saturation (SpO2), rectal temperature, and palpebral and anal reflexes were measured at 5-min intervals. Data were analyzed to compare the effect of anesthetic combinations on induction and recovery times, body reflexes, and physiological variables over time. In both species, K-M gave the shortest induction time, followed by K-X and Z. Palpebral and anal reflexes in chilla foxes immobilized with K-M were maintained in more animals than those treated with either K-X or Z. Animals immobilized with Z had higher heart and respiratory rates than those immobilized with either of the other two combinations. Rectal temperature decreased over time for all combinations. Foxes immobilized with K-M maintained a higher SpO2 than those immobilized with either K-X or with Z. All anesthetic combinations were satisfactory in inducing rapid and safe immobilization of the species studied. The anesthetic plane and the effects on physiologic parameters were better in animals immobilized with K-M than with either K-X or Z, and we recommend this anesthetic combination for use in Chilean foxes. Nevertheless, all three drug combinations used were satisfactory in inducing rapid and relatively smooth anesthesia. 相似文献
92.
93.
Hiroshi Nishiura Gerardo Chowell Muntaser Safan Carlos Castillo-Chavez 《Theoretical biology & medical modelling》2010,7(1):1
Background
In many parts of the world, the exponential growth rate of infections during the initial epidemic phase has been used to make statistical inferences on the reproduction number, R, a summary measure of the transmission potential for the novel influenza A (H1N1) 2009. The growth rate at the initial stage of the epidemic in Japan led to estimates for R in the range 2.0 to 2.6, capturing the intensity of the initial outbreak among school-age children in May 2009. 相似文献94.
Yu Yan Ronald Klein Gerardo Heiss Cynthia J Girman Ethan M Lange Barbara E Klein Kathryn M Rose Eric Boerwinkle James S Pankow Frederick L Brancati Christie M Ballantyne Anna Köttgen Kari E North 《BMC endocrine disorders》2010,10(1):1-10
Background
To investigate disease progression the first 12 months after diagnosis in children with type 1 diabetes negative (AAB negative) for pancreatic autoantibodies [islet cell autoantibodies(ICA), glutamic acid decarboxylase antibodies (GADA) and insulinoma-associated antigen-2 antibodies (IA-2A)]. Furthermore the study aimed at determining whether mutations in KCNJ11, ABCC8, HNF1A, HNF4A or INS are common in AAB negative diabetes.Materials and methods
In 261 newly diagnosed children with type 1 diabetes, we measured residual β-cell function, ICA, GADA, and IA-2A at 1, 6 and 12 months after diagnosis. The genes KCNJ11, ABCC8, HNF1A, HNF4A and INS were sequenced in subjects AAB negative at diagnosis. We expressed recombinant K-ATP channels in Xenopus oocytes to analyse the functional effects of an ABCC8 mutation.Results
Twenty-four patients (9.1%) tested AAB negative after one month. Patients, who were AAB-negative throughout the 12-month period, had higher residual β-cell function (P = 0.002), lower blood glucose (P = 0.004), received less insulin (P = 0.05) and had lower HbA1c (P = 0.02) 12 months after diagnosis. One patient had a heterozygous mutation leading to the substitution of arginine at residue 1530 of SUR1 (ABCC8) by cysteine. Functional analyses of recombinant K-ATP channels showed that R1530C markedly reduced the sensitivity of the K-ATP channel to inhibition by MgATP. Morover, the channel was highly sensitive to sulphonylureas. However, there was no effect of sulfonylurea treatment after four weeks on 1.0-1.2 mg/kg/24 h glibenclamide.Conclusion
GAD, IA-2A, and ICA negative children with new onset type 1 diabetes have slower disease progression as assessed by residual beta-cell function and improved glycemic control 12 months after diagnosis. One out of 24 had a mutation in ABCC8, suggesting that screening of ABCC8 should be considered in patients with AAB negative type 1 diabetes. 相似文献95.
Jan Bartacek Isabella Manconi Gerardo Sansone Roberta Murgia Piet N.L. Lens 《Nitric oxide》2010,22(2):101-105
Hydrogen sulfide (H2S) inhibits the last step of the denitrification process, i.e. the reduction of nitrous oxide (N2O) to dinitrogen gas (N2), both in natural environments (marine sediments) and industrial processes (activated sludge, methanogenic sludge, BioDeNOx process). In a previously published study, we showed that the inhibitory effect of sulfide to N2O reduction in mixed microbial communities is reversible and can be counteracted by dosing trace amounts of copper. It remained, however, unclear if this was due to copper sulfide precipitation or a retrofitting of the copper containing N2O-reductase (N2OR). The present study aimed to elucidate the mechanism of the restoration of sulfide-inhibited N2O reducing activity by metal addition to a pure Pseudomonas aeruginosa culture. This was done by using other metals (zinc, cobalt and iron) in comparison with copper. Zinc and cobalt clearly alleviated the sulfide inhibition of N2OR to the same extent as copper and the activity restoration was extremely fast (within 15 min, Fig. 3) for zinc, cobalt and copper. This suggests that the alleviation of the inhibitory effect of sulfide is due to metal sulfide precipitation and thus not exclusively limited to Cu. This work also underlines the importance of metal speciation: supply of iron did not restore the N2OR activity because it was precipitated by the phosphates present in the medium and thus could not precipitate the sulfide. 相似文献
96.
González R Wilkerson R Suárez MF García F Gallego G Cárdenas H Posso CE Duque MC 《Memórias do Instituto Oswaldo Cruz》2007,102(3):255-262
The genetic variation and population structure of three populations of Anopheles darlingi from Colombia were studied using random amplified polymorphic markers (RAPDs) and amplified fragment length polymorphism markers (AFLPs). Six RAPD primers produced 46 polymorphic fragments, while two AFLP primer combinations produced 197 polymorphic fragments from 71 DNA samples. Both of the evaluated genetic markers showed the presence of gene flow, suggesting that Colombian An. darlingi populations are in panmixia. Average genetic diversity, estimated from observed heterozygosity, was 0.374 (RAPD) and 0.309 (AFLP). RAPD and AFLP markers showed little evidence of geographic separation between eastern and western populations; however, the F ST values showed high gene flow between the two western populations (RAPD: F ST = 0.029; Nm: 8.5; AFLP: F ST = 0.051; Nm: 4.7). According to molecular variance analysis (AMOVA), the genetic distance between populations was significant (RAPD:phiST = 0.084; AFLP:phiST = 0.229, P < 0.001). The F ST distances and AMOVAs using AFLP loci support the differentiation of the Guyana biogeographic province population from those of the Chocó-Magdalena. In this last region, Chocó and Córdoba populations showed the highest genetic flow. 相似文献
97.
Gonzalez MA Alvarez Mdel L Pisani GB Bernal CA Roma MG Carrillo MC 《Biological trace element research》2007,116(3):329-348
We have shown that aluminum (Al) induces cholestasis associated with multiple alterations in hepatocellular transporters involved
in bile secretory function, like Mrp2. This work aims to investigate whether these harmful effects are mediated by the oxidative
stress caused by the metal. For this purpose, the capability of the antioxidant agent, vitamin E, to counteract these alterations
was studied in male Wistar rats. Aluminum hydroxide (or saline in controls) was administered ip (27 mg/kg body weight, three
times a week, for 90 d). Vitamin E (600 mg/kg body weight) was coadministered, sc. Al increased lipid peroxidation (+50%)
and decreased hepatic glutation levels (-43%) and the activity of glutation peroxidase (-50%) and catalase (-88%). Vitamin
E counteracted these effects total or partially. Both plasma and hepatic Al levels reached at the end of the treatment were
significantly reduced by vitamin E (-40% and -44%, respectively;p< 0.05). Al increased 4 times the hepatic apoptotic index, and this effect was fully counteracted by vitamin E. Bile flow
was decreased in Al-treated rats (-37%) and restored to normality by vitamin E. The antioxidant normalized the hepatic handling
of the Mrp2 substrates, rose bengal, and dinitrophenyl-S-glutathione, which was causally associated with restoration of Mrp2
expression. Our data indicate that oxidative stress has a crucial role in cholestasis, apoptotic/necrotic hepatocellular damage,
and the impairment in liver transport function induced by Al and that vitamin E counteracts these harmful effects not only
by preventing free-radical formation but also by favoring Al disposal. 相似文献
98.
Silvia Flores-Benítez Juan F. Jiménez-Bremont Sergio Rosales-Mendoza Gerardo R. Argüello-Astorga Rosalba Castillo-Collazo Ángel Gabriel Alpuche-Solís 《Plant Cell, Tissue and Organ Culture》2007,91(3):215-224
Agave salmiana was transformed using two different protocols: co-cultivation with Agrobacterium tumefaciens and particle bombardment. The uidA (β-glucuronidase) gene was used as a reporter gene for both methods whereas the nptII and bar genes were used as selectable markers for A. tumefaciens and biolistic transformation respectively. Previous reports for in vitro regeneration of A. salmiana have not been published; therefore the conditions for both shoot regeneration and rooting were optimized using leaves and
embryogenic calli of Agave salmiana. The transgenes were detected by Polymerase Chain Reaction (PCR) in 11 month old plants. The transgenic nature of the plants
was also confirmed using GUS histochemical assays. Transformation via co-cultivation of explants with Agrobacterium harbouring the pBI121 binary vector was the most effective method of transformation, producing 32 transgenic plants and giving
a transformation efficiency of 2.7%. On the other hand, the biolistic method produced transgenic calli that tested positive
with the GUS assay after 14 months on selective medium while still undergoing regeneration. 相似文献
99.
Structural relationships between diverse cis-acting elements are critical for the functional properties of a rbcS minimal light regulatory unit 总被引:1,自引:0,他引:1
100.