728 research outputs found

    Brain Drain: Post Graduation Migration Intentions and the influencing factors among Medical Graduates from Lahore, Pakistan

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    <p>Abstract</p> <p>Background</p> <p>The increasing migration of health professionals to affluent countries is not a recent phenomenon and has been addressed in literature. However the various facets of physician migration from Pakistan, the third leading source of International medical graduates has not been rigorously evaluated. The objective of the current study was to survey final year students and recent medical graduates in Lahore, Pakistan about their intentions to train abroad, their post training plans as well as to identify the factors responsible for their motivation for international migration.</p> <p>Method</p> <p>A self administered structured questionnaire was developed to collect respondents' demographic and educational characteristics, intention to train abroad, their preferred destination & post training intentions of returning to Pakistan. Various influencing factors which impact on medical graduate's motivation to train abroad or stay in Pakistan were explored using a 10 point scale. SPSS software was used for data entry and analysis.</p> <p>Results</p> <p>Of the 400 eligible respondents, 275 responded (response rate 68.7%). One hundred and sixty six respondents (60.4%) intended to train abroad either for a specialty (54.9%) or a subspecialty (5.5%) The United States and United Kingdom were the most preferred destination. While 14.2% intended to return to Pakistan immediately after training, a significant percentage (10%) never intended to return to Pakistan or wished to stay abroad temporarily (37%). Professional excellence and establishing quickly in the competitive market were the most important goal to be achieved by the respondents for intention for postgraduate training abroad. The most common reasons cited for training abroad were the impact of residency training on future career (mean score 8.20 ± 2.3), financial conditions of doctors (mean score 7.97 ± 2.37) and job opportunities (mean score7.90 ± 2.34).</p> <p>Conclusion</p> <p>An alarming percentage of medical graduates from Lahore, Pakistan intend to migrate for post graduate training, mainly to United States. A significant proportion wished to stay in the host country either temporarily or indefinitely. Impact of residency abroad on future career, financial conditions of doctors, job opportunities and better working conditions were some of the motivating factors behind the migration.</p

    New Eco-Friendly Polymeric-Coated Urea Fertilizers Enhanced Crop Yield in Wheat

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    [EN] Presently, there is a growing interest in developing new controlled-release fertilizers based on ecological raw materials. The present study aims to compare the efficacy of two new ureic-based controlled-release fertilizers formulated with water-soluble polymeric coatings enriched with humic acids or seaweed extracts. To this end, an experimental approach was designed under controlled greenhouse conditions by carrying out its subsequent field scaling. Different physiological parameters and crop yield were measured by comparing the new fertilizers with another non polymeric-coated fertilizer, ammonium nitrate, and an untreated 'Control'. As a result, on the microscale the fertilizer enriched with humic acids favored a better global response in the photosynthetic parameters and nutritional status of wheat plants. A significant 1.2-fold increase in grain weight yield and grain number was obtained with the humic acid polymeric fertilizer versus that enriched with seaweed extracts; and also, in average, higher in respect to the uncoated one. At the field level, similar results were confirmed by lowering N doses by 20% when applying the humic acid polymeric-coated produce compared to ammonium nitrate. Our results showed that the new humic acid polymeric fertilizer facilitated crop management and reduced the environmental impact generated by N losses, which are usually produced by traditional fertilizers.This research was funded by the Spanish Ministry of Economy and Competitiveness, grant number RTC-2014-1457-5, with the project entitled "Los CRFs como alternativa a los fertilizantes tradicionales: buscando una mayor proteccion del medio ambiente".Gil-Ortiz, R.; Naranjo, MÁ.; Ruiz-Navarro, A.; Caballero-Molada, M.; Atares, S.; GarcĂ­a, C.; Vicente, O. (2020). New Eco-Friendly Polymeric-Coated Urea Fertilizers Enhanced Crop Yield in Wheat. Agronomy. 10(3):1-15. https://doi.org/10.3390/agronomy10030438S115103FAOSTAThttp://www.fao.org/faostat/en/#data/QCFeng, J., Li, F., Deng, A., Feng, X., Fang, F., & Zhang, W. (2016). Integrated assessment of the impact of enhanced-efficiency nitrogen fertilizer on N2O emission and crop yield. Agriculture, Ecosystems & Environment, 231, 218-228. doi:10.1016/j.agee.2016.06.038Barakat, M., Cheviron, B., & Angulo-Jaramillo, R. (2016). Influence of the irrigation technique and strategies on the nitrogen cycle and budget: A review. Agricultural Water Management, 178, 225-238. doi:10.1016/j.agwat.2016.09.027Zak, D. R., Holmes, W. E., MacDonald, N. W., & Pregitzer, K. S. (1999). Soil Temperature, Matric Potential, and the Kinetics of Microbial Respiration and Nitrogen Mineralization. Soil Science Society of America Journal, 63(3), 575-584. doi:10.2136/sssaj1999.03615995006300030021xAchat, D. L., Augusto, L., Gallet-Budynek, A., & Loustau, D. (2016). Future challenges in coupled C–N–P cycle models for terrestrial ecosystems under global change: a review. Biogeochemistry, 131(1-2), 173-202. doi:10.1007/s10533-016-0274-9Di, H. J., & Cameron, K. C. (2016). Inhibition of nitrification to mitigate nitrate leaching and nitrous oxide emissions in grazed grassland: a review. Journal of Soils and Sediments, 16(5), 1401-1420. doi:10.1007/s11368-016-1403-8Akelah, A. (1996). Novel utilizations of conventional agrochemicals by controlled release formulations. Materials Science and Engineering: C, 4(2), 83-98. doi:10.1016/0928-4931(96)00133-6Shaviv, A., & Mikkelsen, R. L. (1993). Controlled-release fertilizers to increase efficiency of nutrient use and minimize environmental degradation - A review. Fertilizer Research, 35(1-2), 1-12. doi:10.1007/bf00750215Xiaoyu, N., Yuejin, W., Zhengyan, W., Lin, W., Guannan, Q., & Lixiang, Y. (2013). 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Advances in Agronomy, 267-322. doi:10.1016/s0065-2113(09)01008-6Diez, J. A., Caballero, R., Bustos, A., Roman, R., Cartagena, M. C., & Vallejo, A. (1996). Control of nitrate pollution by application of controlled release fertilizer (CRF), compost and an optimized irrigation system. Fertilizer Research, 43(1-3), 191-195. doi:10.1007/bf00747701Halvorson, A. D., Snyder, C. S., Blaylock, A. D., & Del Grosso, S. J. (2014). Enhanced‐Efficiency Nitrogen Fertilizers: Potential Role in Nitrous Oxide Emission Mitigation. Agronomy Journal, 106(2), 715-722. doi:10.2134/agronj2013.0081Carson, L. C., & Ozores-Hampton, M. (2013). Factors Affecting Nutrient Availability, Placement, Rate, and Application Timing of Controlled-release Fertilizers for Florida Vegetable Production Using Seepage Irrigation. HortTechnology, 23(5), 553-562. doi:10.21273/horttech.23.5.553Azeem, B., KuShaari, K., Man, Z. B., Basit, A., & Thanh, T. H. (2014). Review on materials & methods to produce controlled release coated urea fertilizer. Journal of Controlled Release, 181, 11-21. doi:10.1016/j.jconrel.2014.02.020Herrera, J., Rubio, G., HĂ€ner, L., Delgado, J., Lucho-Constantino, C., Islas-Valdez, S., & Pellet, D. (2016). Emerging and Established Technologies to Increase Nitrogen Use Efficiency of Cereals. Agronomy, 6(2), 25. doi:10.3390/agronomy6020025Dou, H., & Alva, A. K. (1998). Nitrogen uptake and growth of two citrus rootstock seedlings in a sandy soil receiving different controlled-release fertilizer sources. Biology and Fertility of Soils, 26(3), 169-172. doi:10.1007/s003740050363Feng, C., LĂŒ, S., Gao, C., Wang, X., Xu, X., Bai, X., 
 Wu, L. (2015). «Smart» Fertilizer with Temperature- and pH-Responsive Behavior via Surface-Initiated Polymerization for Controlled Release of Nutrients. ACS Sustainable Chemistry & Engineering, 3(12), 3157-3166. doi:10.1021/acssuschemeng.5b01384Kenawy, E.-R. (1998). Recent Advances in Controlled Release of Agrochemicals. Journal of Macromolecular Science, Part C: Polymer Reviews, 38(3), 365-390. doi:10.1080/15583729808546028Majeed, Z., Ramli, N. K., Mansor, N., & Man, Z. (2015). A comprehensive review on biodegradable polymers and their blends used in controlled-release fertilizer processes. Reviews in Chemical Engineering, 31(1). doi:10.1515/revce-2014-0021Chowdhury, M. A. (2014). The controlled release of bioactive compounds from lignin and lignin-based biopolymer matrices. International Journal of Biological Macromolecules, 65, 136-147. doi:10.1016/j.ijbiomac.2014.01.012FernĂĄndez-PĂ©rez, M., Garrido-Herrera, F. J., GonzĂĄlez-Pradas, E., Villafranca-SĂĄnchez, M., & Flores-CĂ©spedes, F. (2008). Lignin and ethylcellulose as polymers in controlled release formulations of urea. Journal of Applied Polymer Science, 108(6), 3796-3803. doi:10.1002/app.27987Abalos, D., Jeffery, S., Sanz-Cobena, A., Guardia, G., & Vallejo, A. (2014). Meta-analysis of the effect of urease and nitrification inhibitors on crop productivity and nitrogen use efficiency. Agriculture, Ecosystems & Environment, 189, 136-144. doi:10.1016/j.agee.2014.03.036Battacharyya, D., Babgohari, M. Z., Rathor, P., & Prithiviraj, B. (2015). Seaweed extracts as biostimulants in horticulture. Scientia Horticulturae, 196, 39-48. doi:10.1016/j.scienta.2015.09.012Calvo, P., Nelson, L., & Kloepper, J. W. (2014). Agricultural uses of plant biostimulants. Plant and Soil, 383(1-2), 3-41. doi:10.1007/s11104-014-2131-8Canellas, L. P., Olivares, F. L., Aguiar, N. O., Jones, D. L., Nebbioso, A., Mazzei, P., & Piccolo, A. (2015). Humic and fulvic acids as biostimulants in horticulture. Scientia Horticulturae, 196, 15-27. doi:10.1016/j.scienta.2015.09.013Colla, G., Nardi, S., Cardarelli, M., Ertani, A., Lucini, L., Canaguier, R., & Rouphael, Y. (2015). Protein hydrolysates as biostimulants in horticulture. Scientia Horticulturae, 196, 28-38. doi:10.1016/j.scienta.2015.08.037Du Jardin, P. (2015). Plant biostimulants: Definition, concept, main categories and regulation. Scientia Horticulturae, 196, 3-14. doi:10.1016/j.scienta.2015.09.021Birrenkott, B. A., Craig, J. L., & McVey, G. R. (2005). A Leach Collection System to Track the Release of Nitrogen from Controlled-release Fertilizers in Container Ornamentals. HortScience, 40(6), 1887-1891. doi:10.21273/hortsci.40.6.1887Clark, M. J., & Zheng, Y. (2015). Species-specific fertilization can benefit container nursery crop production. Canadian Journal of Plant Science, 95(2), 251-262. doi:10.4141/cjps-2014-340Cox, D. A. (1993). Reducing nitrogen leaching‐losses from containerized plants: The effectiveness of controlled‐release fertilizers. Journal of Plant Nutrition, 16(3), 533-545. doi:10.1080/01904169309364552Agegnehu, G., Nelson, P. N., & Bird, M. I. (2016). The effects of biochar, compost and their mixture and nitrogen fertilizer on yield and nitrogen use efficiency of barley grown on a Nitisol in the highlands of Ethiopia. Science of The Total Environment, 569-570, 869-879. doi:10.1016/j.scitotenv.2016.05.033Huett, D. O., & Gogel, B. J. (2000). Longevities and nitrogen, phosphorus, and potassium release patterns of polymer‐coated controlled‐release fertilizers at 30°C and 40°C. Communications in Soil Science and Plant Analysis, 31(7-8), 959-973. doi:10.1080/00103620009370490YANG, L., WANG, L., LI, H., QIU, J., & LIU, H. (2014). Impacts of Fertilization Alternatives and Crop Straw Incorporation on N2O Emissions from a Spring Maize Field in Northeastern China. Journal of Integrative Agriculture, 13(4), 881-892. doi:10.1016/s2095-3119(13)60496-7Harrison, R., & Webb, J. (2001). A review of the effect of N fertilizer type on gaseous emissions. Advances in Agronomy, 65-108. doi:10.1016/s0065-2113(01)73005-2Obreza, T. A., Rouse, R. E., & Sherrod, J. B. (1999). Economics of Controlled-Release Fertilizer Use on Young Citrus Trees. Journal of Production Agriculture, 12(1), 69-73. doi:10.2134/jpa1999.0069GarcĂ­a, C., Vallejo, A., DiĂ©z, J. A., GarcĂ­a, L., & Cartagena, M. C. (1997). Nitrogen use efficiency with the application of controlled release fertilizers coated with Kraft pine lignin. Soil Science and Plant Nutrition, 43(2), 443-449. doi:10.1080/00380768.1997.10414768Medina, L. C., Sartain, J. B., Obreza, T. A., Hall, W. L., & Thiex, N. J. (2014). Evaluation of a Soil Incubation Method to Characterize Nitrogen Release Patterns of Slow- and Controlled-Release Fertilizers. Journal of AOAC INTERNATIONAL, 97(3), 643-660. doi:10.5740/jaoacint.13-065Gasparin, E., Araujo, M. M., Saldanha, C. W., & Tolfo, C. V. (2015). Controlled release fertilizer and container volumes in the production of Parapiptadenia rigida (Benth.) Brenan seedlings. Acta Scientiarum. Agronomy, 37(4), 473. doi:10.4025/actasciagron.v37i4.19528Haver, D. L., & Schuch, U. K. (1996). Production and Postproduction Performance of Two New Guinea Impatiens Cultivars Grown with Controlled-release Fertilizer and No Leaching. Journal of the American Society for Horticultural Science, 121(5), 820-825. doi:10.21273/jashs.121.5.820Jacobs, D. F., Salifu, K. F., & Seifert, J. R. (2005). Growth and nutritional response of hardwood seedlings to controlled-release fertilization at outplanting. Forest Ecology and Management, 214(1-3), 28-39. doi:10.1016/j.foreco.2005.03.053Kaplan, L., TlustoĆĄ, P., SzĂĄkovĂĄ, J., & NajmanovĂĄ, J. (2013). The influence of slow-release fertilizers on potted chrysanthemum growth and nutrient consumption &nbsp; Plant, Soil and Environment, 59(No. 9), 385-391. doi:10.17221/45/2013-pseKinoshita, T., Yano, T., Sugiura, M., & Nagasaki, Y. (2014). Effects of Controlled-Release Fertilizer on Leaf Area Index and Fruit Yield in High-Density Soilless Tomato Culture Using Low Node-Order Pinching. PLoS ONE, 9(11), e113074. doi:10.1371/journal.pone.0113074Kinoshita, T., Yamazaki, H., Inamoto, K., & Yamazaki, H. (2016). Analysis of yield components and dry matter production in a simplified soilless tomato culture system by using controlled-release fertilizers during summer–winter greenhouse production. Scientia Horticulturae, 202, 17-24. doi:10.1016/j.scienta.2016.02.019Oliet, J., Planelles, R., Segura, M. L., Artero, F., & Jacobs, D. F. (2004). Mineral nutrition and growth of containerized Pinus halepensis seedlings under controlled-release fertilizer. Scientia Horticulturae, 103(1), 113-129. doi:10.1016/j.scienta.2004.04.019Pack, J. E., Hutchinson, C. M., & Simonne, E. H. (2006). Evaluation of Controlled-Release Fertilizers for Northeast Florida Chip Potato Production. Journal of Plant Nutrition, 29(7), 1301-1313. doi:10.1080/01904160600767633Vishtal, A., & Kraslawski, A. (2011). Challenges in industrial applications of technical lignins. BioResources, 6(3), 3547-3568. doi:10.15376/biores.6.3.vishtalCacco, G., AttinĂ , E., Gelsomino, A., & Sidari, M. (2000). Effect of nitrate and humic substances of different molecular size on kinetic parameters of nitrate uptake in wheat seedlings. Journal of Plant Nutrition and Soil Science, 163(3), 313-320. doi:10.1002/1522-2624(200006)163:33.0.co;2-uNardi, S., Ertani, A., & Francioso, O. (2016). Soil-root cross-talking: The role of humic substances. Journal of Plant Nutrition and Soil Science, 180(1), 5-13. doi:10.1002/jpln.201600348Michalak, I., GĂłrka, B., Wieczorek, P. P., RĂłj, E., Lipok, J., Ɓęska, B., 
 Chojnacka, K. (2016). Supercritical fluid extraction of algae enhances levels of biologically active compounds promoting plant growth. European Journal of Phycology, 51(3), 243-252. doi:10.1080/09670262.2015.1134813Lötze, E., & Hoffman, E. W. (2015). Nutrient composition and content of various biological active compounds of three South African-based commercial seaweed biostimulants. Journal of Applied Phycology, 28(2), 1379-1386. doi:10.1007/s10811-015-0644-zGaju, O., DeSilva, J., Carvalho, P., Hawkesford, M. J., Griffiths, S., Greenland, A., & Foulkes, M. J. (2016). Leaf photosynthesis and associations with grain yield, biomass and nitrogen-use efficiency in landraces, synthetic-derived lines and cultivars in wheat. Field Crops Research, 193, 1-15. doi:10.1016/j.fcr.2016.04.018Richards, R. A. (2000). Selectable traits to increase crop photosynthesis and yield of grain crops. Journal of Experimental Botany, 51(suppl_1), 447-458. doi:10.1093/jexbot/51.suppl_1.447Ji, Y., Liu, G., Ma, J., Xu, H., & Yagi, K. (2012). Effect of controlled-release fertilizer on nitrous oxide emission from a winter wheat field. Nutrient Cycling in Agroecosystems, 94(1), 111-122. doi:10.1007/s10705-012-9532-yGrunes, D. L. (1959). Effect of Nitrogen on the Availability of Soil and Fertilizer Phosphorus to Plants. Advances in Agronomy, 369-396. doi:10.1016/s0065-2113(08)60127-3Zhao, B., Dong, S., Zhang, J., & Liu, P. (2013). Effects of Controlled-Release Fertiliser on Nitrogen Use Efficiency in Summer Maize. PLoS ONE, 8(8), e70569. doi:10.1371/journal.pone.0070569Dong, Y. J., He, M. ., Wang, Z. ., Chen, W. ., Hou, J., Qiu, X. ., & Zhang, J. . (2016). Effects of new coated release fertilizer on the growth of maize. Journal of soil science and plant nutrition, (ahead), 0-0. doi:10.4067/s0718-95162016005000046Mi, W., Yang, X., Wu, L., Ma, Q., Liu, Y., & Zhang, X. (2016). Evaluation of Nitrogen Fertilizer and Cultivation Methods for Agronomic Performance of Rice. Agronomy Journal, 108(5), 1907-1916. doi:10.2134/agronj2016.01.0038Roshanravan, B., Mahmoud Soltani, S., Mahdavi, F., Abdul Rashid, S., & Khanif Yusop, M. (2014). Preparation of encapsulated urea-kaolinite controlled release fertiliser and their effect on rice productivity. Chemical Speciation & Bioavailability, 26(4), 249-256. doi:10.3184/095422914x14146901352512Morikawa, C. K., Saigusa, M., Nakanishi, H., Nishizawa, N. K., Hasegawa, K., & Mori, S. (2004). Co-situsapplication of controlled-release fertilizers to alleviate iron chlorosis of paddy rice grown in calcareous soil. Soil Science and Plant Nutrition, 50(7), 1013-1021. doi:10.1080/00380768.2004.10408568Morikawa, C. K., Saigusa, M., Nishizawa, N. K., & Mori, S. (2008). Importance of contact between rice roots and co-situs applied fertilizer granules on iron absorption by paddy rice in a calcareous paddy soil. Soil Science and Plant Nutrition, 54(3), 467-472. doi:10.1111/j.1747-0765.2008.00254.

    Barriers to colorectal cancer screening in Asia: A systematic review

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    Purpose: Colorectal cancer (CRC) is among the top five cancers afflicting both men and women globally. Once predominantly a Western disease, it has begun to rise in Asian countries as well. This systematic review aims to compile and analyze the various barriers towards colorectal cancer screening in Asia, and to determine if the barriers are consistent throughout the continent.Methods: Article Inclusion criteria for based on year of publication from year 2008 till 2015, has been conducted in Asia, and written in English language. A total of 23 studies were included in this review, chosen via primary search of journal websites and databases, and a secondary search through the reference lists of eligible articles.Results: It was found that major barriers of colorectal cancer screening are; poor education/knowledge, negative perceptions towards screening, aversion to test results, financial constraints, time constraints, lack of physicians’ recommendation, limited/difficult access to screening locations, fatalistic beliefs, low perceived risks, language barriers, confidence in traditional medicine/distrust in Western medicine,ignorance and old age.Conclusion: Lack of knowledge/education is the most critical barrier that is linked to a majority of other barriers that can hinder a person from undergoing CRC screening for early prevention, detection and treatment. Majority of these barriers encountered regarding the poor rates of CRC screening are similar across countries in Asia.Keywords: Colorectal cancer screening, Barrier, Knowledge, Criteria for eligibilit

    Space‐time analysis of TIMED Doppler Interferometer (TIDI) measurements

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    Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/95273/1/grl12774.pd

    Stanley's conjecture for critical ideals

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    Let S=K[x_1,x_2,...,x_n] be a polynomial ring in n variables over a field K. Stanley's conjecture holds for the modules I and S/I, when I is a critical monomial ideal. We calculate the Stanley depth of S/I when I is a canonical critical monomial ideal. For non critical monomial ideals we show the existence of a Stanley ideal with the same depth and Hilbert function.Comment: 5 page

    Natural gas consumption and economic growth: cointegration, causality and forecast error variance decomposition tests for Pakistan

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    This paper examines the relationship between natural gas consumption and economic growth in Pakistan using a multivariate model by including capital and labor as the control variables for the periods of 1972-2009. The results of the ARDL bounds testing indicate the presence of cointegration among the variables. The estimated long-run impact of gas consumption (0.49) on economic growth is greater than other factor inputs suggesting that energy is a critical driver of production and growth in Pakistan. Furthermore, the results of causality test and variance decomposition analysis suggest a unidirectional causality running from natural gas consumption to economic growth. Gas being the primary source of energy in Pakistan, the implications of this study is that natural gas conservation policies could harm growth and, therefore, requires the policy makers to improve the energy supply efficiency as well as formulate appropriate policy to attract investment and establish public-private partnership initiatives

    Big data issues and processing techniques: a comprehensive survey

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    Big data and its analysis are in the focus of current era of big data. The main production sources of big data are social media like Facebook, twitter, emails, mobile applications and the migration of manual to automatic of almost every entity. Currently, there is a need to investigate and process complex and huge sets of information-rich data in all fields. This paper provides a survey of big data issues and the effectual and efficient platforms and technologies which are needed to deal and process the remarkable amount of data. It revolves around two important areas namely: clustering and scheduling

    Chronic hypoxemia increases myocardial cytochrome oxidase

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    ObjectiveCyanotic patients have potentially decreased tissue oxygen tension. Cytochrome oxidase catalyzes the reduction of oxygen and is integral to adenosine triphosphate production. Cytochrome oxidase subunit I, the active site, is encoded by mitochondrial DNA. Using a newborn swine model of chronic hypoxemia, we evaluated ventricular cytochrome oxidase subunit I mRNA and protein expression and assessed cytochrome oxidase activity.MethodsThirty-two newborn piglets underwent thoracotomy and placement of a pulmonary artery–to–left atrium shunt or sham operation. Two weeks later, partial pressure of arterial oxygen, hematocrit, and left ventricular shortening fraction values were compared with baseline values. Northern blot hybridization and protein immunoblotting for ventricular cytochrome oxidase subunit I were performed. Cytochrome oxidase kinetic activity was measured. Heme a,a3 content and turnover number were determined. Significance was assessed with a t test.ResultsBaseline partial pressure of arterial oxygen and hematocrit values were similar. Hypoxemic piglets had a lower partial pressure of arterial oxygen of 38 ± 10 mm Hg (P < .001) and higher hematocrit value of 31.4% ± 2.9% (P < .001) compared with a partial pressure of arterial oxygen of 140 ± 47 mm Hg and hematocrit value of 24.6% ± 3.9% after the sham operation. Baseline and postprocedure left ventricular shortening fraction were similar within and between groups. Chronic hypoxemia increased right ventricular and left ventricular cytochrome oxidase I mRNA and protein by more than 1.4-fold. Cytochrome oxidase activity increased significantly in hypoxemia by 2.5-fold compared with that seen after the sham operation. Heme a,a3 content and turnover number increased by 1.5-fold during hypoxemia.ConclusionsChronic hypoxemia increases cytochrome oxidase I message, protein expression, and activity. The increase in kinetics was due to increased enzyme content and catalytic activity. This is a possible adaptive mechanism that might preserve organ function during chronic hypoxemia
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