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1.
J Environ Manage ; 355: 120539, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38461640

RESUMO

Rising carbon emissions caused by population growth and industrialization is a significant environmental challenge in various countries. To combat this issue, Renewable Energy (RE) and Carbon Capture and Storage (CCS) technologies should be commercialized to reduce Greenhouse Gas (GHG) emissions and generate carbon-free energy. One such technology is the use of microalgae, which can directly capture CO2 from the air through photosynthesis and potentially produce biofuels due to their high energy content. However, the carbon capture rate of microalgae varies globally due to numerous parameters and variables affecting microalgae productivity. Additionally, microalgae productivity and carbon capture formulas yield different results worldwide, especially in outdoor industrial-scale cultivation. This research aims to comprehensively review the effective variables and parameters in carbon capture by microalgae based on microalgae productivity and carbon capture formulas. The research also ranked countries based on CO2 production in four different categories to determine whether the biggest carbon producer countries could exhibit suitable weather conditions for microalgae cultivation. Findings reveal optimal ranges of critical variables in the microalgae growth formula, including temperature, solar radiation intensity, Photon Flux Density (PFD), and sunlight duration. The study also analyzes microalgae cultivation, carbon capture, and oxygen production formula in different systems such as Open Ponds (OP), Tubular Photobioreactors (TPBR), and Flat Plate Photobioreactors (FPPBR), while discussing other influential parameters. In conclusion, emphasizing the adjustment and utilization of optimal values of effective parameters in microalgae cultivation not only holds promise for future carbon capture by microalgae but also pushes human beings toward sustainable development goals.


Assuntos
Microalgas , Humanos , Carbono , Dióxido de Carbono , Biomassa , Fotobiorreatores , Biocombustíveis
2.
Environ Sci Pollut Res Int ; 30(47): 103556-103575, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37715906

RESUMO

The relationship between water, energy, food, and the environment has piqued the interest of the global community due to the critical interdependence of these resources for long-term development. This article investigates research within the field of the quadruple nexus. Data from Scopus documents, with the keywords "water, energy, food, and environment" from 2011 to 2022, were processed and analyzed. Further research revealed that scientific exploration of the water-energy-food-environment relationship is rapidly expanding. The Scopus database was used to extract information about countries, institutions, highly cited publications, keywords, hot topics, and future research trends for this study. Additionally, the VOSviewer bibliometric software was employed to evaluate the scientific citations in this article. The results indicated that the USA, compared to other nations, publishes a larger quantity of articles in this field. Recently, China, India, and Middle Eastern countries have garnered significant attention and have been extensively researched. The Philippines, Finland, and Iran have also emerged among the top nations publishing recent articles on the water-energy-food-environment nexus (WEFEN). This article attempts to study the bibliography on the WEFEN connection, identify popular topics, and discern the fields of future studies in this discussion. Furthermore, it investigates the effects of economic and social factors as well as the impact of the COVID-19 pandemic on this quadruple nexus.


Assuntos
COVID-19 , Humanos , Pandemias , Bibliometria , China , Água
3.
Environ Sci Pollut Res Int ; 30(40): 91729-91745, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37531064

RESUMO

This paper investigates biomass and solar energy's present and future perspectives in low/zero energy and carbon emissions. Its data source is published articles indexed in the Scopus database. By analyzing the articles extracted in Vos viewer software, four main areas of research are found: sustainable development, economic and managerial issues, methods, algorithms, modeling technologies, and renewable energy and its sources and types. In all four sections, research gaps were observed in the field of the third generation of photovoltaics (semi-transparent solar cells )organic)) and algae. As part of the study, advanced bibliometric analysis was carried out by VOS viewer software, and 34129 articles were examined from Scopus, alongside a patent analysis using Google patents, in addition to the bibliometric analysis. It has been shown by machine learning that about 9% of future articles in all energy fields will consist of building articles, and a quarter of these articles will be in the field of renewable energy. While residential and commercial sectors are the dominant areas of renewable energy utilization and commercialization research, the potential of new generations of renewable energy technologies will create significant opportunities to achieve low/zero energy-carbon emission buildings. The paper concludes by predicting the increasing rate of renewable energy and building articles compared to energy articles by 2030, emphasizing the critical role of research in advancing sustainable energy solutions. This data mining analysis helps to identify the current gaps and opportunities. Therefore, great potential will be created to develop and commercialize a new generation of technologies in this industry.


Assuntos
Carbono , Energia Renovável , Luz Solar , Biomassa , Aprendizado de Máquina , Dióxido de Carbono/análise , Desenvolvimento Econômico
4.
Environ Sci Pollut Res Int ; 30(22): 62281-62294, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36935440

RESUMO

A lack of resources and suitable farming lands, climate change, and a rapidly growing population are some of the main concerns of the societies that pose security challenges to the governments. Creating controlled environments for cultivation, growing plants, and farming, such as greenhouses, may assist in overcoming these challenges. Greenhouses can significantly increase land use efficiency in agriculture by increasing crop yield and harvesting throughout the year, which has long been proven effective. The history of greenhouses for farming dates back to Roman times, and there are different barriers to their applications. An example is the provision of energy to control the cultivation conditions of plants in greenhouses, particularly for heating and cooling hot and cold climate areas. On the other hand, based on the global energy trend, decentralized energy production based on solar energy is highly regarded. In the same way, that households can harvest solar energy, greenhouses can also benefit from solar energy. However, because greenhouses need sunlight to cultivate plants, reducing sunlight using common photovoltaic panels is not logical. By incorporating semitransparent solar cells into these greenhouses, the issue of reduced sunlight could be addressed, and further efficiency gains could be achieved by reducing energy demand in these greenhouses. This research investigates the energy supply system's integration with greenhouses consumption. First, we assess different conventional types of greenhouses in terms of energy demand. Then, we investigate the energy demand with organic photovoltaic (OPV) integration for each type. Finally, the best design of the greenhouse for OPV integration is recommended. Results show that flat arch geometry is the best choice for dry and cold climates, while sawtooth geometry showed better improvements in tropical climates. In both temperate/mesothermal and continental/microthermal climates, A-frame geometry showed superiority in energy saving. Simulations revealed an annual electricity generation for a unit floor area of the greenhouses to be 173.7 kWh/m2 to 247.9 MWh/m2 for the optimum structural geometries that decrease the energy consumption of greenhouses. Additionally, the results show that the installation of the OPV can decrease energy consumption from 15 to 58% based on the greenhouse's location and structural geometry.


Assuntos
Energia Solar , Luz Solar , Agricultura/métodos , Ambiente Controlado , Fazendas
5.
J Nucl Med ; 64(5): 704-710, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36460344

RESUMO

Our aim was to report the use of 64Cu and 67Cu as a theranostic pair of radionuclides in human subjects. An additional aim was to measure whole-organ dosimetry of 64Cu and 67Cu attached to the somatostatin analog octreotate using the sarcophagine MeCOSar chelator (SARTATE) in subjects with somatostatin receptor-expressing lesions confined to the cranium, thereby permitting normal-organ dosimetry for the remainder of the body. Methods: Pretreatment PET imaging studies were performed up to 24 h after injection of [64Cu]Cu-SARTATE, and normal-organ dosimetry was estimated using OLINDA/EXM. Subsequently, the trial subjects with multifocal meningiomas were given therapeutic doses of [67Cu]Cu-SARTATE and imaged over several days using SPECT/CT. Results: Five subjects were initially recruited and imaged using PET/CT before treatment. Three of the subjects were subsequently administered 4 cycles each of [67Cu]Cu-SARTATE followed by multiple SPECT/CT imaging time points. No serious adverse events were observed, and no adverse events led to withdrawal from the study or discontinuation from treatment. The estimated mean effective dose was 3.95 × 10-2 mSv/MBq for [64Cu]Cu-SARTATE and 7.62 × 10-2 mSv/MBq for [67Cu]Cu-SARTATE. The highest estimated organ dose was in spleen, followed by kidneys, liver, adrenals, and small intestine. The matched pairing was shown by PET and SPECT intrasubject imaging to have nearly identical targeting to tumors for guiding therapy, demonstrating a potentially accurate and precise theranostic product. Conclusion: 64Cu and 67Cu show great promise as a theranostic pair of radionuclides. Further clinical studies will be required to examine the therapeutic dose required for [67Cu]Cu-SARTATE for various indications. In addition, the ability to use predictive 64Cu-based dosimetry for treatment planning with 67Cu should be further explored.


Assuntos
Neoplasias Meníngeas , Meningioma , Humanos , Meningioma/diagnóstico por imagem , Meningioma/radioterapia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Radioisótopos , Radiometria , Compostos Radiofarmacêuticos/uso terapêutico , Distribuição Tecidual
6.
Environ Sci Pollut Res Int ; 30(3): 7427-7445, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36040695

RESUMO

Energy-exporting countries have always been isolated when it comes to energy security since according to the traditional definition of energy security, it is believed that there are no energy security-associated problems in these countries. Over the recent years, exporting countries have encountered the issue of single-product economy on a much larger scale, due to large oil revenues; they are facing more and more problems in the field of energy security every day. In this regard, the present paper primarily identified the challenges and factors affecting energy security and sustainable development related to energy in these countries. Afterwards, this information was employed for the construction of a composite index to measure the energy security and sustainability in these countries using the fuzzy BWM method. This composite index was utilized for a period of 14 years in five energy-exporting countries, namely Iran, Iraq, Russia, Saudi Arabia, and Venezuela. The results obtained herein were fully consistent with the process of the changes in energy security in the mentioned countries and indicated the weaknesses and obstacles of these countries in the field of oil and oil economy. The results of a 14-year evaluation of the composite index show that Saudi Arabia, followed by Russia, Iran, Iraq, and Venezuela, displays the best performance in the field of energy security and sustainability and has an ascending trend and significant progress in the index value. Although Russia is in second place, it represents a descending trend. Iran, which is in third place on the slope of changes, has a falling but gentler trend. Iraq has a rising trend in the index value despite being in fourth place. The lowest level of energy security belongs to Venezuela with a sharp descending trend and naturally the worst performance in the field of energy security and sustainability. Examining these obstacles, it was observed that the economic-technological issues were a heavier burden than the social and environmental ones. In the economic-technological sector, oil-free per capita GDP, the share of non-energy exports in total exports, and the share of investment in the energy sector in total investment were the biggest obstacles, indicating the urgent need to change macro policies, exit the single-product economy, and adopt policies to increase the value added and reduce the sale of raw energy.


Assuntos
Comércio , Desenvolvimento Sustentável , Irã (Geográfico) , Iraque , Arábia Saudita
7.
Asia Ocean J Nucl Med Biol ; 9(1): 1-8, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33392343

RESUMO

A limitation to the wider introduction of personalised dosimetry in theranostics is the relative paucity of imaging radionuclides with suitable physical and chemical properties to be paired with a long-lived therapeutic partner. As most of the beta-emitting therapeutic radionuclides emit gamma radiation as well they could potentially be used as the imaging radionuclide as well as the therapeutic radionuclide. However, the downsides are that the beta radiation will deliver a significant radiation dose as part of the treatment planning procedure, and the gamma radiation branching ratio is often quite low. Gallium-67 has been in use in nuclear medicine for over 50 years. However, the tremendous interest in gallium imaging in theranostics in recent times has focused on the PET radionuclide gallium-68. In this article it is suggested that the longer-lived gallium-67, which has desirable characteristics for imaging with the gamma camera and a suitably long half-life to match biological timescales for drug uptake and turnover, has been overlooked, in particular, for treatment planning with radionuclide therapy. Gallium-67 could also allow non-PET facilities to participate in theranostic imaging prior to treatment or for monitoring response after therapy. Gallium-67 could play a niche role in the future development of personalised medicine with theranostics.

8.
Sci Rep ; 11(1): 2475, 2021 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-33510222

RESUMO

Positron (ß+) emitting radionuclides have been used for positron emission tomography (PET) imaging in diagnostic medicine since its development in the 1950s. Development of a fluorinated glucose analog, fluorodeoxyglucose, labelled with a ß+ emitter fluorine-18 (18F-FDG), made it possible to image cellular targets with high glycolytic metabolism. These targets include cancer cells based on increased aerobic metabolism due to the Warburg effect, and thus, 18F-FDG is a staple in nuclear medicine clinics globally. However, due to its attention in the diagnostic setting, the therapeutic potential of ß+ emitters have been overlooked in cancer medicine. Here we show the first in vitro evidence of ß+ emitter cytotoxicity on prostate cancer cell line LNCaP C4-2B when treated with 20 Gy of 18F. Monte Carlo simulation revealed thermalized positrons (sub-keV) traversing DNA can be lethal due to highly localized energy deposition during the thermalization and annihilation processes. The computed single and double strand breakages were ~ 55% and 117% respectively, when compared to electrons at 400 eV. Our in vitro and in silico data imply an unexplored therapeutic potential for ß+ emitters. These results may also have implications for emerging cancer theranostic strategies, where ß+ emitting radionuclides could be utilized as a therapeutic as well as a diagnostic agent once the challenges in radiation safety and protection after patient administration of a radioactive compound are overcome.


Assuntos
Partículas beta , Elétrons , Tomografia por Emissão de Pósitrons , Neoplasias da Próstata , Linhagem Celular Tumoral , Fluordesoxiglucose F18/farmacologia , Humanos , Masculino , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/radioterapia , Doses de Radiação , Compostos Radiofarmacêuticos/farmacologia
9.
Asia Ocean J Nucl Med Biol ; 4(1): 30-37, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27904871

RESUMO

OBJECTIVES: Lutetium-177 can be made with high specific activity and with no other isotopes of lutetium present, referred to as "No Carrier Added" (NCA) 177Lu. We have radiolabelled DOTA-conjugated peptide DOTA-(Tyr3)-octreotate with NCA 177Lu ("NCA-LuTATE") and used it in nearly 40 therapeutic administrations for subjects with neuroendocrine tumours or meningiomas. In this paper, we report on our initial studies on aspects of the biodistribution and dosimetry of NCA-LuTATE from gamma camera 2D whole body (WB) and quantitative 3D SPECT (qSPECT) 177Lu imaging. METHODS: Thirteen patients received 39 NCA-LuTATE injections. Extensive WB planar and qSPECT imaging was acquired at approximately 0.5, 4, 24 and 96 h to permit estimates of clearance and radiation dose estimation using MIRD-based methodology (OLINDA-EXM). RESULTS: The average amount of NCA-Lutate administered per cycle was 7839±520 MBq. Bi-exponential modelling of whole body clearance showed half lives for the fast & slow components of t½=2.1±0.6 h and t½=58.1±6.6 h respectively. The average effective dose to kidneys was 3.1±1.0 Gy per cycle. In eight patients completing all treatment cycles the average total dose to kidneys was 11.7±3.6 Gy. CONCLUSIONS: We have shown that NCA-LuTATE has an acceptable radiation safety profile and is a suitable alternative to Carrier-Added 177Lu formulations. The fast component of the radiopharmaceutical clearance was closely correlated with baseline renal glomerular filtration rate, and this had an impact on radiation dose to the kidneys. In addition, it has less radioactive waste issues and requires less peptide per treatment.

10.
Cent Eur J Public Health ; 23(3): 183-7, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26615647

RESUMO

Trends such as aging populations, excess costs, rising public expectations, and progress in medical science and technologies point out the necessity of adaptation and development of innovation in the healthcare systems particularly in developed countries. The main objective of this article is to review diffusion of innovation in the healthcare sector. Different types of innovation, diffusion characteristics, and adoption mechanisms are the subjects that are discussed in the selected case study, Finland. Finally, the key items of innovation management in the Finnish health system are introduced. The results can be implemented in other countries as well.


Assuntos
Inovação Organizacional , Atenção Primária à Saúde/organização & administração , Medicina Estatal/organização & administração , Difusão de Inovações , Eficiência Organizacional , Finlândia , Gastos em Saúde , Humanos , Estudos de Casos Organizacionais , Atenção Primária à Saúde/economia , Medicina Estatal/economia , Recursos Humanos
11.
EJNMMI Phys ; 2(1): 20, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26501821

RESUMO

BACKGROUND: Advances in gamma camera technology and the emergence of a number of new theranostic radiopharmaceutical pairings have re-awakened interest in in vivo quantification with single-photon-emitting radionuclides. We have implemented and validated methodology to provide quantitative imaging of (177)Lu for 2D whole-body planar studies and for 3D tomographic imaging with single-photon emission computed tomography (SPECT)/CT. METHODS: Whole-body planar scans were performed on subjects to whom a known amount of [(177)Lu]-DOTA-octreotate had been administered for therapy. The total radioactivity estimated from the images was compared with the known amount of the radionuclide therapy administered. In separate studies, venous blood samples were withdrawn from subjects after administration of [(177)Lu]-DOTA-octreotate while a SPECT acquisition was in progress and the concentration of the radionuclide in the venous blood sample compared with that estimated from large blood pool structures in the SPECT reconstruction. The total radioactivity contained within an internal SPECT calibration standard was also assessed. RESULTS: In the whole-body planar scans (n = 28), the estimated total body radioactivity was accurate to within +4.6 ± 5.9 % (range -17.1 to +11.2 %) of the correct value. In the SPECT reconstructions (n = 12), the radioactivity concentration in the cardiac blood pool was accurate to within -4.0 ± 7.8 % (range -16.1 to +7.5 %) of the true value and the internal standard measurements (n = 89) were within 2.0 ± 8.5 % (range -16.3 to +24.2 %) of the known amount of radioactivity contained. CONCLUSIONS: In our hands, state-of-the-art hybrid SPECT/CT gamma cameras were able to provide accurate estimates of in vivo radioactivity to better than, on average, ±10 % for use in biodistribution and radionuclide dosimetry calculations.

12.
Asia Ocean J Nucl Med Biol ; 3(2): 107-15, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-27408890

RESUMO

OBJECTIVES: Peptide Receptor Radionuclide Therapy (PRRT) with yttrium-90 ((90)Y) and lutetium-177 ((177)Lu)-labelled SST analogues are now therapy option for patients who have failed to respond to conventional medical therapy. In-house production with automated PRRT synthesis systems have clear advantages over manual methods resulting in increasing use in hospital-based radiopharmacies. We report on our one year experience with an automated radiopharmaceutical synthesis system. METHODS: All syntheses were carried out using the Eckert & Ziegler Eurotope's Modular-Lab Pharm Tracer® automated synthesis system. All materials and methods used were followed as instructed by the manufacturer of the system (Eckert & Ziegler Eurotope, Berlin, Germany). Sterile, GMP-certified, no-carrier added (NCA) (177)Lu was used with GMP-certified peptide. An audit trail was also produced and saved by the system. The quality of the final product was assessed after each synthesis by ITLC-SG and HPLC methods. RESULTS: A total of 17 [(177)Lu]-DOTATATE syntheses were performed between August 2013 and December 2014. The amount of radioactive [(177)Lu]-DOTATATE produced by each synthesis varied between 10-40 GBq and was dependant on the number of patients being treated on a given day. Thirteen individuals received a total of 37 individual treatment administrations in this period. There were no issues and failures with the system or the synthesis cassettes. The average radiochemical purity as determined by ITLC was above 99% (99.8 ± 0.05%) and the average radiochemical purity as determined by HPLC technique was above 97% (97.3 ± 1.5%) for this period. CONCLUSIONS: The automated synthesis of [(177)Lu]-DOTATATE using Eckert & Ziegler Eurotope's Modular-Lab Pharm Tracer® system is a robust, convenient and high yield approach to the radiolabelling of DOTATATE peptide benefiting from the use of NCA (177)Lu and almost negligible radiation exposure of the operators.

13.
Asia Ocean J Nucl Med Biol ; 2(2): 75-86, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-27408863

RESUMO

OBJECTIVES: Gallium-68 (Ga-68) is an ideal research and hospital-based PET radioisotope. Currently, the main form of Ga-68 radiopharmaceutical that is being synthesised in-house is Ga-68 conjugated with DOTA based derivatives. The development of automated synthesis systems has increased the reliability, reproducibility and safety of radiopharmaceutical productions. Here we report on our three year, 500 syntheses experience with an automated system for Ga-68 DOTATATE. METHODS: The automated synthesis system we use is divided into three parts of a) servomotor modules, b) single use sterile synthesis cassettes and, c) a computerised system that runs the modules. An audit trail is produced by the system as a requirement for GMP production. The required reagents and chemicals are made in-. The Germanium breakthrough is determined on a weekly basis. Production yields for each synthesis are calculated to monitor the performance and efficiency of the synthesis. The quality of the final product is assessed after each synthesis by ITLC-SG and HPLC methods. RESULTS: A total of 500 Ga-68 DOTATATE syntheses (>800 patient doses) were performed between March 2011 and February 2014. The average generator yield was 81.3±0.2% for 2011, 76.7±0.4% for 2012 and 75.0±0.3% for 2013. Ga-68 DOTATATE yields for 2011, 2012, and 2013 were 81.8±0.4%, 82.2±0.4% and 87.9±0.4%, respectively. These exceed the manufacturer's expected value of approximately 70%. Germanium breakthrough averaged 8.6×10(-6)% of total activity which is well below the recommended level of 0.001%. The average ITLC-measured radiochemical purity was above 98.5% and the average HPLC-measured radiochemical purity was above 99.5%. Although there were some system failures during synthesis, there were only eight occasions where the patient scans needed to be rescheduled. CONCLUSION: In our experience the automated synthesis system performs reliably with a relatively low incident of failures. Our system had a consistent and reliable Ga-68 DOTATATE output with high labelling efficiency and purity. There is minimal operator intervention and radiation exposure. The system is GMP-compliant and has low maintenance and acceptable running costs. This system together with the recommended (68)Ge/(68)Ga generator is well suited for use in a hospital-based radiopharmacy.

14.
ANZ J Surg ; 82(3): 173-8, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22510129

RESUMO

BACKGROUND: The Whipple's procedure (WP) is a major operation that adds a further demand on the body's nutritional reserves and therefore body composition after the effect of pancreatic cancer. The aim was to document changes in body composition changes that occur during the first six months after a WP for a pancreatic cancer malignancy. METHODS: Twenty-seven (14 males, 13 females) consecutive WP patients had body composition measured at baseline and then at 2, 5, 14 and 26 weeks after surgery. These included; anthropometric measure (weight, skin folds and arm muscle area (AMA)), total body measures of protein (TBP), potassium (TBK), water (TBW) and fat mass (FM). Changes were compared using repeated measures analysis of variance. RESULTS: Hospital nutritional care maintained TBP and TBK but at 2 weeks there was a loss of FM (P= 0.037). The nadir of weight loss (P < 0.001) occurred at 5 weeks because of losses of protein (P= 0.007), fat (P < 0.001) and potassium (P= 0.045) but not water. Although weight and FM were still significantly less than baseline measures at 26 weeks weight, TBP, TBK and AMA were not significantly different to preoperative values. CONCLUSIONS: Although at 6 months, important measures of the metabolically functioning tissue, TBP and TBK, have returned to preoperative values significant losses occurred during the first 3 weeks after discharge from hospital and FM did not return to preoperative values. These results suggest the need to improve post-discharge nutritional care.


Assuntos
Composição Corporal , Neoplasias Pancreáticas/cirurgia , Pancreaticoduodenectomia , Redução de Peso , Adiposidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Biomarcadores/metabolismo , Estudos de Coortes , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Potássio/metabolismo , Proteínas/metabolismo , Resultado do Tratamento
15.
HPB (Oxford) ; 12(5): 325-33, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20590908

RESUMO

OBJECTIVES: Cachexia is common in pancreatic cancer and may have an influence on longterm survival but few studies have investigated this in patients with operable tumours. Therefore, this study was carried out to document body composition status in patients with pancreatic adenocarcinoma (PCa) presenting for a Whipple's procedure (WP) and to relate the findings to histopathology and longterm survival. METHODS: Body composition was measured 1 day before a WP for ductal PCa in 36 patients (15 men, 21 women) aged 41-81 years. Results for total body nitrogen (TBN), nitrogen index (NI), total body water (TBW), fat mass (FM) and total body potassium (TBK) were compared with results in 73 age- and sex-matched controls. Patients' survival and details from histopathology synoptic reports were documented. RESULTS: Patients undergoing WPs had low TBK values (P < 0.001) and females had lower body fat (P = 0.007) compared with controls. Five of 36 presented with significant protein deficiency, but this was not associated with a prolonged length of stay or reduced survival. The 12 patients who had involved surgical margins had larger tumours and reduced weight (P = 0.015), FM (P = 0.001), TBN (P = 0.045), TBK (P = 0.014) and survival (P = 0.036). However, multivariate Cox's regression analysis only included FM along with vascular invasion and margin status as independent predictors of survival. CONCLUSIONS: PCa patients undergoing a WP have reduced body fat and TBK compared with community controls while those with stage III tumours had greater deficits of fat, TBK and protein stores. However, preoperative body composition was a poor predictor of postoperative survival after pathological data were considered.


Assuntos
Composição Corporal , Caquexia/etiologia , Carcinoma Ductal Pancreático/cirurgia , Procedimentos Cirúrgicos do Sistema Digestório , Estado Nutricional , Neoplasias Pancreáticas/cirurgia , Adiposidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Água Corporal/metabolismo , Caquexia/mortalidade , Caquexia/fisiopatologia , Carcinoma Ductal Pancreático/complicações , Carcinoma Ductal Pancreático/mortalidade , Carcinoma Ductal Pancreático/patologia , Carcinoma Ductal Pancreático/fisiopatologia , Estudos de Casos e Controles , Procedimentos Cirúrgicos do Sistema Digestório/efeitos adversos , Procedimentos Cirúrgicos do Sistema Digestório/mortalidade , Feminino , Humanos , Estimativa de Kaplan-Meier , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Estadiamento de Neoplasias , New South Wales , Nitrogênio/análise , Neoplasias Pancreáticas/complicações , Neoplasias Pancreáticas/mortalidade , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/fisiopatologia , Potássio/análise , Modelos de Riscos Proporcionais , Medição de Risco , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
16.
Dalton Trans ; (38): 5173-7, 2008 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-18813371

RESUMO

A reversible crystal-to-crystal transformation of a 3D lead(II) coordination polymer with the ligand 4-pyridinecarboxylic acid (4-Hpyc), from [Pb(4-pyc)(2)(H(2)O)](n) (1) to [Pb(4-pyc)(2)](n) (2) by de- and re-hydration, has been observed and the structures of 1 and 2 were determined by single-crystal X-ray diffraction. The thermal stabilities of compounds 1 and 2 were studied by thermal, gravimetric and differential thermal analyses. Powder X-ray diffraction experiments showed that the phase transitions observed for the single crystals also occur in the batch powder samples and lead to mono phasic products.

17.
Chem Commun (Camb) ; (29): 3402-4, 2008 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-18633503

RESUMO

Single-crystal to single-crystal transformation of a new lead(II) coordination polymer with ligands 8-hydroxyquinoline (8-Quin) and nitrate, [Pb2(8-Quin)2(NO3)2(MeOH)] () to [Pb(8-Quin)(NO3)] (1beta), is reported and the structures of and determined by X-ray crystallography.

18.
Clin Nutr ; 24(6): 943-55, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16083996

RESUMO

BACKGROUND & AIMS: Growth hormone (GH) has a strong anabolic effect and is thought to be useful in improving the efficacy of parenteral nutrition (PN) to preserve muscle mass (MM) in the postoperative setting. Unfortunately, the negative clinical outcome of GH treatment in intensive care patients limits its use in this setting, but demands answers to the mechanism behind the action of this therapy. METHOD: In a double-blind randomised controlled study consecutive patients after major abdominal surgery were divided into four groups of either 1/2-PN (0.13 g N/kg/day and 52% of calories as lipid) or full-strength PN (Full-PN) (0.3 g N/kg/day and 65% of calories as lipid) receiving daily injections of either GH (8-16 IU) or placebo for a period of 14 days postoperative. Outcome measures included MM derived from measures of total body potassium (40K counting) and total body nitrogen (TBN) (in vivo neutron capture technique); Fat mass from skin folds; serum insulin like growth factor-I (IGF-I) and its binding proteins (IGFBP). RESULTS: From 43 major upper GI surgical patients randomised 35 completed the study (one patient died from sepsis in the half-strength PN (1/2-PN)+GH group). 1/2-PN (n=11) lost TBN (P=0.001), MM (P=0.005) but not fat. Full-PN (n=9) maintained TBN, MM (P=0.056) and fat. 1/2-PN+GH (n=8) maintained TBN and fat but lost MM (P=0.038). Full-PN+GH (n=7) maintained TBN and MM but lost fat (P=0.018). Two-way ANOVA indicated that PN input (P=0.031) and not GH had a significant effect on MM. GH caused a significant rise in IGF-I levels (290+/-67 and 454+/-71 microg/l for 1/2-PN+GH and Full-PN+GH, respectively) and restored serum IGFBP3 and the acid labile subunit to normal, by the postoperative day 9. CONCLUSION: After major gastrointestinal surgery, GH causes a marked hepatic IGF-I response and nitrogen retention but its effect on body composition was more significant with a high PN input. Further, Full-PN alone was sufficient to prevent nitrogen loss and preserved MM and addition of GH does not provide further metabolic advantage.


Assuntos
Composição Corporal/efeitos dos fármacos , Hormônio do Crescimento/farmacologia , Músculo Esquelético/efeitos dos fármacos , Nitrogênio/metabolismo , Nutrição Parenteral , Abdome/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Terapia Combinada , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Humanos , Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina/sangue , Fator de Crescimento Insulin-Like I/análise , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/metabolismo , Período Pós-Operatório , Radioisótopos de Potássio , Estudos Prospectivos , Resultado do Tratamento
19.
Ophthalmic Plast Reconstr Surg ; 21(4): 264-6, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16052137

RESUMO

PURPOSE: Orbital cyst formation after enucleation is a rare but serious complication. Complete excision may be difficult, and the final cosmetic result may be poor. In contrast, in this study, intralesional trichloroacetic acid injection proved successful in resolving the problematic cyst without surgical intervention. METHODS: A 20% trichloroacetic acid solution was injected to treat four cases of orbital conjuctival cyst in anophthalmic socket. RESULTS: All four patients were treated successfully. No recurrence or other complications developed. The average follow-up interval was 16 months (range, 8 to 33 months). CONCLUSIONS: Intralesional trichloroacetic acid injection proved successful in resolving the problematic cyst without surgical intervention in anophthalmic orbit. It is a safe procedure and is recommended for treatment of anteriorly located orbital conjuctival cysts.


Assuntos
Cáusticos/uso terapêutico , Doenças da Túnica Conjuntiva/tratamento farmacológico , Cistos/tratamento farmacológico , Enucleação Ocular , Doenças Orbitárias/tratamento farmacológico , Complicações Pós-Operatórias , Ácido Tricloroacético/uso terapêutico , Adulto , Doenças da Túnica Conjuntiva/etiologia , Cistos/etiologia , Humanos , Injeções Intralesionais , Pessoa de Meia-Idade , Doenças Orbitárias/etiologia
20.
Perit Dial Int ; 23(3): 291-5, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12938832

RESUMO

OBJECTIVE: To determine the effect of renal function at the commencement of dialysis on nutritional state. DESIGN: Retrospective cohort study. SETTING: University tertiary referral hospital. PATIENTS: Patients with end-stage renal disease commencing renal replacement therapy over 8.5 years. MAIN OUTCOME MEASURES: Total body nitrogen assessment using in vivo neutron activation analysis, expressed as nitrogen index (NI = observed total body nitrogen/predicted total body nitrogen); serum albumin measurement and creatinine clearance estimation, using the Cockcroft-Gault equation, at the start of dialysis. "Early" start group = creatinine clearance > 10 mL/minute (n = 26). "Late" start group = creatinine clearance < or = 10 mL/min (n = 108). RESULTS: Mean NI was significantly lower [95% confidence interval (CI) 6%-30%, p < 0.0001] in the late start group (NI = 88%) compared to the early start group (NI = 106%). The late start group also had a significantly lower (95% CI 0.06-0.47 g/dL, p = 0.02) mean serum albumin level (3.66 g/dL) compared to that of the early start group (3.93 g/dL). A positive independent correlation existed between renal function and total body nitrogen (r2 = 0.21, p < 0.0001). No other clinical or demographic variable at the start of dialysis was found to predict nutritional state. CONCLUSIONS: Patients that start dialysis with low levels of renal function are likely to be significantly malnourished. Whether this translates into a survival advantage requires prospective study.


Assuntos
Falência Renal Crônica/complicações , Falência Renal Crônica/terapia , Rim/fisiopatologia , Desnutrição/complicações , Estado Nutricional , Diálise Renal , Adulto , Idoso , Estudos de Coortes , Feminino , Humanos , Falência Renal Crônica/fisiopatologia , Testes de Função Renal , Masculino , Desnutrição/fisiopatologia , Pessoa de Meia-Idade , Estudos Retrospectivos , Índice de Gravidade de Doença , Fatores de Tempo
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