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1.
BMC Nurs ; 20(1): 247, 2021 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-34879843

RESUMEN

BACKGROUND: The safe and standard handling of antineoplastic drugs can reduce the effects of occupational exposure and promote safe behaviors in nurses. Thus, the present study aimed to determine the effects ofstandard guidelines education on the safe handling of antineoplastic drugs among oncologynurses in Ardabil, Iran. METHODS: Thequasi-experimental study with a one-group pretest-posttest design was performed among 32 nursesworking in the oncology wards of two educational hospitals in Ardabil city, during 2020. Allthe nurses in the wards who met the inclusion criteria participated in the study. The data were collectedby usinga demographic information form and nurses'knowledge assessment questionnaire regardingthe standard guidelines for working with antineoplastic drugs, and a standard checklist for examiningtheir performance in this regard. Subsequently, they were analyzed by descriptive (mean and standard deviation) and inferential statistics (t-test)and Pearson's correlation coefficient) in SPSS 22. RESULTS: The mean and standard deviation of the knowledge and performance scores of the oncology nurses was59.56±6.41and 18.96±2.54 respectively, which changed to 66±4.82 and 32.03±2.45 respectively three months after training. The results of the t-test represented a statistically significant difference between the level of knowledge and performance before and after the intervention (P=0.001). CONCLUSIONS: Based on the results, the standard guidelines education improved the nurses' knowledge and performance on the safe handling of antineoplastic drugs in the chemotherapy wards. Therefore, it is advised to increase the awareness of the oncology nurses in this regard in the planning and policy-making ofhealthcare centers.

2.
Langmuir ; 33(51): 14728-14737, 2017 12 26.
Artículo en Inglés | MEDLINE | ID: mdl-29182875

RESUMEN

In this study, a novel technique was introduced for selective surface modification of amine-functionalized magnetic nanoparticles. The method was based on alignment of magnetic nanoparticles in an external magnetic field, which resulted in formation of chain-like assemblies in diluted suspensions. The aligned chains were then modified on the surface via reaction of isocyanate species with the particle functionalities. Finally, after removal from the reactor medium, particles with segmented distribution of surface functionalities were achieved. We named these partially blocked amine-functionalized magnetic nanoparticles as "Saturn" nanoparticles. Application of the particles in fabrication of magnetic assemblies was successfully demonstrated. Using methylene diphenyl diisocyanate (MDI) as the bridging agent, structures in different forms such as chains and filaments were produced by the Saturn particles and compared with cross-linked structures of the unmodified amine-functionalized particles. It is expected that this novel nanoparticle with its unique structure will have great potential in assembly fabrication with a variety of applications in biomedical fields.

3.
J Clin Pharm Ther ; 42(6): 704-709, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28597926

RESUMEN

WHAT IS KNOWN AND OBJECTIVE: Albumin has been frequently used as a therapeutic agent based on previous recommendations that are mostly controversial. Considering limited evidence-based indications, common inappropriate albumin use in many hospitals necessitates prompt educational and regulatory interventions. We performed this study to assess the effect of a hospital-wide programme to optimize albumin use in a tertiary referral university-affiliated hospital. METHODS: This study was conducted in three 45-day phases, separated by two sequential interventions: guideline implementation and albumin order-sheet consideration. We evaluated albumin use and assessed its appropriateness in each phase at baseline, after guideline implementation and after order-sheet consideration. RESULTS: We recorded 100, 93 and 71 albumin orders for 100, 84 and 66 patients during the first, second and third phases, respectively. The adjusted number of albumin orders (used albumin vials) was 94.9 (1481.7 vials), 80.8 (1037.6 vials) and 66 (1219 vials) in the first, second and third phases of the study, respectively. Albumin orders with appropriate indication increased significantly over the three phases of the study (OR=1.5, P=.008). The frequency of inappropriate orders reduced significantly from the first phase to the third phase (58%-27%, P=.007). WHAT IS NEW AND CONCLUSION: The pattern and amount of albumin use changed following guideline implementation and order-sheet consideration, and inappropriate albumin use was reduced in our hospital. There was still room for improvement, particularly for indications that were not included in the guideline. Hence, a more comprehensive guideline, frequent audit, feedback and interactive educational approaches might be necessary to achieve results that are of a greater magnitude.


Asunto(s)
Albúminas/uso terapéutico , Revisión de la Utilización de Medicamentos/métodos , Femenino , Hospitales Universitarios , Humanos , Masculino , Persona de Mediana Edad , Centros de Atención Terciaria
4.
East Mediterr Health J ; 22(12): 860-864, 2017 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-28181660

RESUMEN

We examined the role of Helicobacter pylori infection as a cause of recurrent abdominal pain (RAP) among Iranian children in a population-based case-control study to determine the association between H. pylori infection and RAP among schoolchildren. A total of 1558 children aged 6-13 years were examined. Children with RAP confirmed by the Apley and Naish criteria were selected; 145 cases were selected for inclusion and were compared with 145 healthy children recruited from the same area. Both groups underwent stool antigen testing. The prevalence of RAP in the children tested was 9.3%. Children with RAP had a higher H. pylori infection rate than the control group (58.6% vs 44.8%) (OR = 1.744; 95% CI: 1.095-2.776). There was no significant difference between the RAP symptoms in children with positive stool test, i.e. infected with H. pylori, and those whose tests were negative. We identified H. pylori infection in more than 55% of the case group. Therefore, H. pylori infection can be considered an important factor for RAP in children.


Asunto(s)
Dolor Abdominal/epidemiología , Infecciones por Helicobacter/epidemiología , Helicobacter pylori/aislamiento & purificación , Adolescente , Estudios de Casos y Controles , Niño , Femenino , Humanos , Irán/epidemiología , Masculino , Prevalencia
5.
East. Mediterr. health j ; 22(12): 860-864, 2016-12.
Artículo en Inglés | WHO IRIS | ID: who-260286

RESUMEN

We examined the role of Helicobacter pylori infection as a cause of recurrent abdominal pain [RAP] among Iranian children in a population-based case-control study to determine the association between H. pylori infection and RAP among schoolchildren. A total of 1558 children aged 6-13 years were examined. Children with RAP confirmed by the Apley and Naish criteria were selected; 145 cases were selected for inclusion and were compared with 145 healthy children recruited from the same area. Both groups underwent stool antigen testing. The prevalence of RAP in the children tested was 9.3%. Children with RAP had a higher H. pylori infection rate than the control group [58.6% vs 44.8%] [OR = 1.744; 95% CI: 1.095-2.776]. There was no significant difference between the RAP symptoms in children with positive stool test, i.e. infected with H. pylori, and those whose tests were negative. We identified H. pylori infection in more than 55% of the case group. Therefore, H. pylori infection can be considered an important factor for RAP in children


Nous avons examiné le rôle de l'infection par Helicobacter pylori en tant que cause de douleur abdominale récurrente parmi des enfants iraniens au cours d'une étude cas-témoin populationnelle afin de déterminer l'association entre cette infection et la douleur abdominale récurrente chez les enfants scolarisés. Au total, 1558 enfants âgés de 6 à 13 ans ont été examinés. Des enfants souffrant d'une douleur abdominale récurrente confirmée selon les critères définis par Apley et Naish ont été sélectionnés: 145 cas répondant au critère d'inclusion ont été comparés avec 145 enfants en bonne santé de la même région. Les deux groupes ont été soumis à un test de recherche d'antigènes dans les selles. L'incidence de la douleur abdominale récurrente testée était de 9,3%. Les enfants ayant une douleur abdominale récurrente présentaient un taux d'infection par H. pylori plus élevé que le groupe témoin [58,6% contre 44,8% ; OR = 1,744 et IC à 95%: 1,095-2,776]. Il n'y avait pas de différence significative entre les symptômes de douleur abdominale récurrente chez les enfants ayant des coprocultures positives, donc une infection par H. pylori, et ceux dont les tests étaient négatifs. Nous avons identifié une infection par H. pylori chez plus de 55% d'enfants du groupe témoin. Par conséquent, l'infection par H. pylori peut être considérée comme un facteur important de douleur abdominale chez l'enfant


Asunto(s)
Infecciones por Helicobacter , Helicobacter pylori , Dolor Abdominal , Niño , Heces , Estudios de Casos y Controles
6.
Ann Nucl Med ; 29(10): 877-82, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26286635

RESUMEN

OBJECTIVE: Molecular imaging with positron emission tomography (PET) provides a powerful means of identifying and characterizing cancerous processes, as well as providing a quantitative framework within which response to therapy can be ascertained. Unfortunately, the most commonly used PET radiotracer, ¹8F-fluorodeoxyglucose (FDG), has not demonstrated a definitive role in determining response to therapy in metastatic renal cell carcinoma (RCC). As a result, new radiotracers able to reliably image RCC could be of tremendous value for this purpose. METHODS: Five patients with known metastatic RCC were imaged with the low-molecular weight radiotracer ¹8F-DCFPyL, an inhibitor of the prostate-specific membrane antigen at 60 min post injection. ¹8F-DCFPyL PET/CT and conventional images (either contrast-enhanced computed tomography or magnetic resonance imaging) were centrally reviewed for suspected sites of disease. RESULTS: In all five patients imaged, sites of putative metastatic disease were readily identifiable by abnormal ¹8F-DCFPyL uptake, with overall more lesions detected than on conventional imaging. These PET-detected sites included lymph nodes, pancreatic parenchymal lesions, lung parenchymal lesions, a brain parenchymal lesion, and other soft tissue sites. ¹8F-DCFPyL uptake ranged from subtle to intense with maximum standardized uptake values (SUVmax) for the identified lesions of 1.6-19.3. Based upon this small patient series, limited pathology and imaging follow-up of these patients suggests a higher sensitivity for ¹8F-DCFPyL compared to conventional imaging in the detection of metastatic RCC (94.7 versus 78.9%). CONCLUSIONS: PSMA expression in the tumor neovasculature of RCC has been previously established and is believed to provide the basis for the imaging findings presented here. PSMA-based PET/CT with radiotracers such as ¹8F-DCFPyL may allow more accurate staging of patients with RCC and conceivably the ability to predict and follow therapy in patients treated with agents targeting the neovasculature.


Asunto(s)
Antígenos de Superficie/metabolismo , Carcinoma de Células Renales/diagnóstico , Glutamato Carboxipeptidasa II/metabolismo , Neoplasias Renales/diagnóstico , Lisina/análogos & derivados , Imagen Multimodal , Tomografía de Emisión de Positrones , Tomografía Computarizada por Rayos X , Urea/análogos & derivados , Anciano , Carcinoma de Células Renales/diagnóstico por imagen , Carcinoma de Células Renales/patología , Humanos , Neoplasias Renales/diagnóstico por imagen , Neoplasias Renales/patología , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia
7.
Phys Chem Chem Phys ; 17(5): 3490-6, 2015 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-25533590

RESUMEN

A clearer understanding of calcite interactions with organic molecules would contribute to a range of fields including harnessing the secrets of biomineralisation where organisms produce hard parts, increasing oil production from spent reservoirs, remediating contaminated soils and drinking water aquifers and improving manufacturing methods for industrial products such as pigments, soft abrasives, building materials and optical devices. Biomineralisation by some species of blue green algae produces beautifully elaborate platelets of calcite where the individual crystals are of nanometer scale. Controlling their growth requires complex polysaccharides. Polysaccharide activity depends on the functionality of OH groups, so to simplify the system in order to get closer to a molecular level understanding, we investigated the interaction of OH from a suite of alcohols with clean, freshly cleaved calcite surfaces. X-ray photoelectron spectroscopy (XPS) provided binding energies and revealed the extent of surface coverage. Molecular dynamics (MD) simulations supplemented with information about molecule ordering, orientation and packing density. The results show that all alcohols studied bond with the calcite surface through the OH group, with their carbon chains sticking away in a standing-up orientation. Alcohol molecules are closely packed and form a well-ordered monolayer on the surface.


Asunto(s)
Alcoholes/química , Carbonato de Calcio/química , Adsorción , Etano/química , Etanol/química , Interacciones Hidrofóbicas e Hidrofílicas , Simulación de Dinámica Molecular , Espectroscopía de Fotoelectrones , Polisacáridos/química , Propiedades de Superficie , Agua/química
8.
Bone Marrow Transplant ; 49(6): 818-23, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24614837

RESUMEN

Oral mucositis (OM) is a complication of high-dose chemotherapy (HDC) which is frequently observed in hematopoietic SCT settings. Antioxidant agents have been proposed to prevent OM and therefore N-acetyl cysteine (NAC) could have an important role. In the present study, we conducted a double-blind, randomized, placebo-controlled study to evaluate the NAC effect on OM incidence and severity, and also glutathione peroxidase-1 activity. Leukemia patients undergoing allogeneic hematopoietic SCT preceded by HDC were recruited into the study and received either NAC (100 mg/kg/day) (n=38) or placebo (n=42) from the starting day of HDC until day +15 after transplantation. OM was evaluated daily for 21 days after transplantation according to World Health Organization oral toxicity scale. The incidence of severe OM (grades 3-4) was significantly lower in the NAC group (23.7% vs 45.3%, P=0.04). Moreover, the mean duration of OM was significantly shorter in the intervention group (6.24(2.96) vs 8.12(3.97) days, P=0.02). The glutathione peroxidase-1 activity was also significantly higher in the NAC group seven days after transplantation (3.38(2.19) vs 2.41(1.70) ng/mL, P=0.003). It is concluded that parenteral NAC is effective in reducing the incidence of severe cases and the total duration of OM.


Asunto(s)
Acetilcisteína/uso terapéutico , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Estomatitis/prevención & control , Acetilcisteína/efectos adversos , Adulto , Aloinjertos , Antioxidantes/efectos adversos , Antioxidantes/uso terapéutico , Método Doble Ciego , Femenino , Glutatión Peroxidasa/sangre , Neoplasias Hematológicas/terapia , Humanos , Masculino , Persona de Mediana Edad , Estomatitis/etiología , Adulto Joven , Glutatión Peroxidasa GPX1
9.
Eur Rev Med Pharmacol Sci ; 17(7): 964-70, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23640445

RESUMEN

BACKGROUND: Nitric oxide (NO) and its toxic product peroxynitrite contribute to oxidative stress and neurodegeneration in Parkinson's disease (PD). The relationship of serum levels of these oxidants with the severity of the disease [evaluated by the Unified Parkinson's Disease Rating Scale (UPDRS)] is not established. AIM: This study was designed to evaluate whether patients with PD had higher NO and peroxynitrite serum level or not. PATIENTS AND METHODS: Fifty eight patients with PD and 15 healthy volunteers entered this study. The concentrations of serum NO and peroxynitrite were assayed and their correlation with the UPDRS score was assessed. RESULTS: Mean serum NO levels in patient group was 29.8 ± 21.631 versus 7.49 ± 2.573 in control group, which was significantly higher in patients (p ≤ 0.0001). Peroxynitrite levels in patient and control groups were 7.37±3.501 µmol/L and 3.94 ±1.389 µmol/L respectively. Patients had a significantly higher peroxynitrite level (p = 0.0004). CONCLUSIONS: Higher levels of NO and peroxynitrite leads to higher UPDRS scores. It seems since current PD treatments do not affect the pathology of the disease, using drugs that exert neuroprotective properties should be considered for the treatment of PD in order to prevent further neuronal cell loss.  


Asunto(s)
Óxido Nítrico/sangre , Estrés Oxidativo , Enfermedad de Parkinson/sangre , Ácido Peroxinitroso/sangre , Anciano , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedad de Parkinson/metabolismo , Índice de Severidad de la Enfermedad
10.
Eur Rev Med Pharmacol Sci ; 17(4): 447-50, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23467941

RESUMEN

BACKGROUND: Non-depolarizing neuromuscular blocking agents (NMB) differ in pharmacokinetic and pharmacodynamic parameters. An anesthesiologist according to these similarities and differences is able to choose the least costly one if the same safety profile and same clinical benefit achieved with the different alternatives. AIM: The main objective of this study is to evaluate the economic and adverse drug reactions prevalence and differences between cisatracurium and atracurium the two non-depolarizing NMB drugs, which are widely used in adult patients undergoing surgery with general anesthesia in a teaching Hospital in Iran. MATERIALS AND METHODS: A cost analysis and adverse drug reactions (ADR) monitoring were performed. Only direct costs were considered and data were collected through a prospective randomized study. Regardless of the type of surgery, 100 patients were randomly divided into two equal groups to receive either cisatracurium or atracurium by anesthesiologists. ADRs prevalence and cost differences between patients receiving one of the two non-depolarizing NMB agents were evaluated by independent sample t-test and Chi-square test respectively. RESULTS: No significant difference was observed between the two groups of patients in demographic data. There was no statistical difference in the ADR prevalence in both groups. The numbers of ADR within atracurium group was higher than cisatracurium group, but this distinction was not statistically significant (p > 0.05). It was significant difference in cost between the two neuromuscular blocking drugs (p < 0.05). CONCLUSIONS: According to our study it seems that atracurium and cisatracurium had similar safety profile and atracurium had a cost benefit relative to cisatracurium in initial loading doses. In patients with instability in hemodynamic parameters the cisatracurium was the appropriate choice.  


Asunto(s)
Anestesia General/métodos , Atracurio/análogos & derivados , Costos de los Medicamentos , Fármacos Neuromusculares no Despolarizantes , Adulto , Atracurio/efectos adversos , Atracurio/economía , Atracurio/uso terapéutico , Costos y Análisis de Costo , Femenino , Hospitales de Enseñanza , Humanos , Irán , Masculino , Persona de Mediana Edad , Fármacos Neuromusculares no Despolarizantes/efectos adversos , Fármacos Neuromusculares no Despolarizantes/economía , Fármacos Neuromusculares no Despolarizantes/uso terapéutico , Estudios Prospectivos
11.
ISRN Neurol ; 2012: 786526, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22928117

RESUMEN

Background. Multiple sclerosis (MS) is an autoimmune inflammatory disease of central nervous system (CNS). MS affects quality of Life (QOL) due to physical disability and other associated problems. Disease-modifying agents like interferon beta (IFNB) have been widely utilized in this patient population; however, their frequency, route of administration, side effects, high cost, and also the question of whether they are truly beneficial for longer-term outcomes and QOL need to be further investigated. Objectives. To assess QOL in patients with multiple sclerosis receiving interferon beta-1a (Avonex or CinnoVex) and in order to compare QOL in groups receiving Avonex and CinnoVex, respectively, also, to evaluate whether the more cost-effective biosimilar form of IFNB (CinnoVex) has the same effect on QOL and can be substituted for Avonex. Methods. We conducted a 30-month, nonrandomized longitudinal study and recruited a total of 92 patients diagnosed with relapsing-remitting MS. The patients were distributed in Avonex and CinnoVex groups with 46 patients in each group. Quality of life was assessed by means of MSQOL-54 questionnaire, four times a year, at baseline and at months 4, 8, and 12 of the study. Results. Mean age ± SD was 30.5 ± 8.9 and 32.3 ± 9.0 years in Avonex and CinnoVex groups, respectively, and P value of gender was different (P value : 0.036). The physical health composite scores were 61.8 and 59.8 (P values 0.677 and 0.884) for Avonex and CinnoVex groups, in that order. The results of the study revealed no significant difference between the two groups with regard to physical health, health perception, energy, and role limitations due to physical problems, pain, sexual and social function, and physical health distress scores. Further, interferon therapy did not significantly impact patients' QOL after a year of treatment with either Avonex or CinnoVex. Conclusions. According to the present study, treatment with IFNB (Avonex or CinnoVex) did not affect QOL during a year of therapy. Further studies with longer follow-up periods are required to assess the value of interferons on long-term outcomes and patient's QOL.

12.
Curr Med Chem ; 19(5): 763-9, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22214446

RESUMEN

Phencyclidine (I) and its derivatives show such pharmacological behaviors as analgesic, anticonsulvant, anti-anxiety and antidepressant, while interacting with central nervous system. In this study, new methyl and hydroxyl derivatives of PCP were synthesized and their antinociceptive behaviors in animals were examined by measuring the number of writhing in a writhing test of visceral pain and the pain scores in Formalin test. Compared to control and PCP groups, findings in experimental groups indicated the new synthesized analogues (compounds II, III and V, 10 mg/kg) of PCP were able to produce more analgesic effects in formalin and writhing tests, especially for compound V. It was concluded that the new synthesized derivatives of PCP could substantially and respectively diminish acute and chronic pains.


Asunto(s)
Analgésicos/síntesis química , Fenciclidina/farmacología , Dolor Visceral/tratamiento farmacológico , Analgésicos/química , Animales , Dimensión del Dolor , Fenciclidina/análogos & derivados , Fenciclidina/síntesis química , Relación Estructura-Actividad
13.
Br J Ophthalmol ; 94(11): 1464-7, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20576763

RESUMEN

BACKGROUNDS: To evaluate the efficacy of 2% topical ciclosporin A in treating and preventing graft rejection episodes after penetrating keratoplasty (PKP) in patients with a history of graft rejection episodes. METHODS: In this prospective, randomised, double-blind clinical trial, a group of PKP patients were randomly given 2% topical ciclosporin A (group 1) or a placebo (group 2) in addition to a corticosteroid regimen upon an episode of subepithelial or endothelial graft rejection. The topical ciclosporin and placebo were continued for 6 months. The duration of corticosteroid application and the time to resolution of the rejection episode for which ciclosporin or placebo was started, the number of concurrent and subsequent rejection episodes, and the rate of rejection-free survival were compared between the two groups. RESULTS: 22 eyes of 22 patients (12 men) were in group 1 and 21 eyes of 21 patients (10 men) were in group 2. Mean patient age was 32.48 (11.9 years and 35.48 (11.7 years in groups 1 and 2, respectively (p = 0.42). Mean follow-up period was 16.6 (6.1 months and 16.0 (6.3 months (p = 0.75) and the episode for which 2% topical ciclosporin or placebo was started completely resolved after 25.6 (21.0 days and 33.2 (16.7 days in groups 1 and 2, respectively (p = 0.22). The rejection-free graft survival rate was 34.8% in group 1 and 31.7% in group 2 at month 20 (p = 0.89). Conclusion 2% topical ciclosporin A did not add any advantage to conventional corticosteroid treatment in terms of treating and preventing graft rejection in PKP patients with previous history of rejection episodes.


Asunto(s)
Ciclosporina/administración & dosificación , Rechazo de Injerto/prevención & control , Inmunosupresores/administración & dosificación , Queratoplastia Penetrante/métodos , Administración Tópica , Adolescente , Adulto , Distrofias Hereditarias de la Córnea/cirugía , Femenino , Rechazo de Injerto/tratamiento farmacológico , Supervivencia de Injerto , Humanos , Estimación de Kaplan-Meier , Queratocono/cirugía , Masculino , Persona de Mediana Edad , Prevención Secundaria , Resultado del Tratamiento , Adulto Joven
14.
J Phys Chem A ; 113(25): 7011-20, 2009 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-19462959

RESUMEN

Smog chamber/FTIR techniques were used to determine rate constants of k(Cl+n-butanol) = (2.21 +/- 0.38) x 10(-10) and k(OH+n-butanol) = (8.86 +/- 0.85) x 10(-12) cm(3) molecule(-1) s(-1) in 700 Torr of N(2)/O(2) diluent at 296 +/- 2K. The sole primary product identified from the Cl atom initiated oxidation of n-butanol in the absence of NO was butyraldehyde (38 +/- 2%, molar yield). The primary products of the Cl atom initiated oxidation of n-butanol in the presence of NO were (molar yield) butyraldehyde (38 +/- 2%), propionaldehyde (23 +/- 3%), acetaldehyde (12 +/- 4%), and formaldehyde (33 +/- 3%). The substantially lower yields of propionaldehyde, acetaldehyde, and formaldehyde as primary products in experiments conducted in the absence of NO suggests that chemical activation is important in the atmospheric chemistry of CH(3)CH(2)CH(O)CH(2)OH and CH(3)CH(O)CH(2)CH(2)OH alkoxy radicals. The primary products of the OH radical initiated oxidation of n-butanol in the presence of NO were (molar yields) butyraldehyde (44 +/- 4%), propionaldehyde (19 +/- 2%), and acetaldehyde (12 +/- 3%). In all cases, the product yields were independent of oxygen concentration over the partial pressure range of 10-600 Torr. The yields of propionaldehyde, acetaldehyde, and formaldehyde quoted above were not corrected for secondary formation via oxidation of higher aldehydes and should be treated as upper limits. The reactions of Cl atoms and OH radicals with n-butanol proceed 38 +/- 2 and 44 +/- 4%, respectively, via attack on the alpha-position to give an alpha-hydroxy alkyl radical which reacts with O(2) to give butyraldehyde. The results are discussed with respect to the atmospheric chemistry of n-butanol.


Asunto(s)
1-Butanol/química , Atmósfera/química , Cloro/química , Radical Hidroxilo/química , Óxido Nítrico/química , Cinética , Oxidación-Reducción , Espectroscopía Infrarroja por Transformada de Fourier
15.
J Phys Chem A ; 112(35): 8053-60, 2008 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-18693707

RESUMEN

Smog chamber/FTIR techniques were used to study the atmospheric chemistry of 3-pentanol and determine rate constants of k(Cl+3-pentanol) = (2.03 +/- 0.23) x 10 (-10) and k(OH+3-pentanol) = (1.32 +/- 0.15) x 10 (-11) cm (3) molecule (-1) s (-1) in 700 Torr of N 2/O 2 diluent at 296 +/- 2 K. The primary products of the Cl atom initiated oxidation of 3-pentanol in the absence of NO were (with molar yields) 3-pentanone (26 +/- 2%), propionaldehyde (12 +/- 2%), acetaldehyde (13 +/- 2%) and formaldehyde (2 +/- 1%). The primary products of the Cl atom initiated oxidation of 3-pentanol in the presence of NO were (with molar yields) 3-pentanone (51 +/- 4%), propionaldehyde (39 +/- 2%), acetaldehyde (44 +/- 4%) and formaldehyde (4 +/- 1%). The primary products of the OH radical initiated oxidation of 3-pentanol in the presence of NO were (with molar yields) 3-pentanone (58 +/- 3%), propionaldehyde (28 +/- 2%), and acetaldehyde (37 +/- 2%). In all cases the product yields were independent of oxygen concentration over the partial pressure range 10-700 Torr. The reactions of Cl atoms and OH radicals with 3-pentanol proceed 26 +/- 2 and 58 +/- 3%, respectively, via attack on the 3-position to give an alpha-hydroxyalkyl radical, which reacts with O 2 to give 3-pentanone. The results are discussed with respect to the literature data and atmospheric chemistry of 3-pentanol.


Asunto(s)
Atmósfera/química , Cloro/química , Radical Hidroxilo/química , Óxido Nítrico/química , Pentanoles/química , Contaminantes Atmosféricos/química , Cinética , Oxidación-Reducción , Espectroscopía Infrarroja por Transformada de Fourier
16.
J Anim Physiol Anim Nutr (Berl) ; 92(1): 99-104, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18184385

RESUMEN

The effect of a diet containing trans fatty acids (TFA) on the fatty acid composition and fat accumulation was investigated in broiler chickens. Female broilers were fed a control or a TFA-containing diet. The difference between the diets was that a part of cis 18:1 in the control diet was replaced by the TFA. Body composition, energy balance and the fatty acid composition were examined. Over the time-period studied (15 days), the body fat content and the protein content did not differ significantly between the TFA-fed group and the control. In energy balance studies, total energy intake, energy loss in excreta, energy expenditure and energy storage did not differ between the treatments. Compared to the control diet, the TFA diet resulted in significantly higher amounts of 14:0 and 18:1n-7 and lower amounts of 18:1n-9 and 20:4n-6 in the body. In conclusion, the data suggest that feeding TFA for 15 days to female broilers had no effect on energy retention, energy expenditure and energy loss in excreta or in body composition in terms of fat and protein. Only the fatty acid composition in the body was affected by the treatment with TFA. In addition, 50% of ingested TFA was incorporated into the body fat. This may have a negative effect on the dietetic value of chicken meat.


Asunto(s)
Tejido Adiposo/química , Composición Corporal/efectos de los fármacos , Pollos/metabolismo , Metabolismo Energético/efectos de los fármacos , Ácidos Grasos trans/administración & dosificación , Alimentación Animal , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Composición Corporal/fisiología , Metabolismo Energético/fisiología , Femenino , Isomerismo , Distribución Aleatoria , Ácidos Grasos trans/química , Ácidos Grasos trans/metabolismo
17.
Environ Sci Technol ; 41(21): 7389-95, 2007 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-18044516

RESUMEN

Smog chamber/FTIR techniques were used to study the atmospheric chemistry of the title compound which we refer to as RfOC2H5. Rate constants of k(Cl + RfOC2H5) = (2.70 +/- 0.36) x 10(-12), k(OH + RfOC2H5) = (5.93 +/- 0.85) x 10(-14), and k(Cl + RfOCHO) = (1.34 +/- 0.20) x 10(-14) cm3 molecule(-1') s(-1) were measured in 700 Torr of N2, or air, diluent at 294 +/- 1 K. From the value of k(OH + RfOC2H5) the atmospheric lifetime of RfOC2H5 was estimated to be 1 year. Two competing loss mechanisms for RfOCH(O*)CH3 radicals were identified in 700 Torr of N2/O2 diluent at 294 +/- 1 K; decomposition via C-C bond scission giving a formate (RfOCHO), or reaction with 02 giving an acetate (RfOC(O)CH3). In 700 Torr of N2/O2 diluent at 294 +/- 1 K the rate constant ratio k(O2)/k(diss) = (1.26 +/- 0.74) x 10(-19) cm3 molecule(-1). The OH radical initiated atmospheric oxidation of RfOC2H5 gives Rf0CHO and RfOC(O)CH3 as major products. RfOC2H5 has a global warming potential of approximately 55 for a 100 year horizon. The results are discussed with respect to the atmospheric chemistry and environmental impact of RfOC2H5.


Asunto(s)
Cloro/química , Furanos/química , Hidrocarburos Fluorados/química , Radical Hidroxilo/química , Contaminantes Atmosféricos/química , Ambiente , Cinética , Oxidación-Reducción
18.
J Anim Physiol Anim Nutr (Berl) ; 91(11-12): 492-7, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17988353

RESUMEN

Feeding mice conjugated linoleic acid (CLA) reduces body fat. Soluble fibre decreases apparent lipid digestibility. The objective of the present study was to examine whether a combination of dietary CLA and soluble fibre would further decrease the proportion of body fat than a diet with CLA alone. Therefore, we fed mice diets with CLA and different amounts of Nutrim, containing 10% soluble fibre. CLA was added to the control diet at the expense of high oleic acid sunflower oil (HOSF) component and Nutrim was added at the expense of an isoenergetic combination of starch, dextrose and cellulose. The diets were fed for 28 days. Weight gain after 28 days was less in CLA-fed animals than in HOSF-fed animals. Both CLA and Nutrim increased the body water content. CLA reduced total body fat and epidydymal fat but Nutrim did not. No interaction of CLA and fibre was detected. We, therefore, must conclude that under the present experimental conditions dietary CLA and fibre do not interact to reduce body fat deposition.


Asunto(s)
Tejido Adiposo/efectos de los fármacos , Composición Corporal/efectos de los fármacos , Fibras de la Dieta/administración & dosificación , Ácidos Linoleicos Conjugados/administración & dosificación , Aumento de Peso , Tejido Adiposo/crecimiento & desarrollo , Tejido Adiposo/metabolismo , Animales , Grasas Insaturadas en la Dieta/administración & dosificación , Digestión , Relación Dosis-Respuesta a Droga , Masculino , Ratones , Ratones Endogámicos BALB C , Tamaño de los Órganos/efectos de los fármacos , Distribución Aleatoria , Solubilidad
19.
Eur J Ophthalmol ; 17(1): 20-8, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17294379

RESUMEN

PURPOSE: To determine characteristics and final visual and surgical outcomes of patients who experienced early onset postoperative inflammation after cataract surgery and their early and late complications. METHODS: This is a prospective case series of 126 patients out of 1500 cases who underwent cataract surgery and experienced early onset postoperative inflammation during the first 2 weeks after cataract surgery. All the patients received complete ocular examinations at onset of signs and symptoms of inflammation. A total of 110 patients with follow-up examinations between 3 and 30 months after recovery of early onset postoperative inflammation (mean follow-up 11.6 months) were enrolled in the next part of the study to evaluate the final visual and surgical outcomes. Background systemic and ocular diseases, type of surgery, type of intraocular lenses and viscoelastic agent, early and late complications, and final best-corrected visual acuity were studied. RESULTS: Among 1500 patients, 126 cases (8.4%) had early onset postoperative inflammation, 64 cases (50.7%) were male, and 62 cases (49.3%) were female. Early complications were posterior synechia in 9 cases (7.1%), pupillary block in 2 cases (1.5%), and acute rise of intraocular pressure in 6 cases (4.7%). Late complications consisted of posterior capsular opacity in 38 cases (34.5%) and cystoid macular edema in 4 cases (3.2%). Peak of signs and symptoms of inflammation was during 2 weeks after surgery and all patients responded well to topical steroids. Final best-corrected visual acuity (BCVA) was 20/30 and better in 76 cases (69%), between 20/40 and 20/80 in 24 cases (22%), and less than 20/80 in 10 cases (9%). All cases with BCVA less than 20/80 had ocular diseases like choroidal neovascularization scar or age-related macular degeneration, advanced glaucoma, or corneal opacity. CONCLUSIONS: Early onset postoperative inflammation causes pain, decreased vision, and patient anxiety in the acute phase but neither decreases final visual acuity nor has any significant or permanent ocular sequels.


Asunto(s)
Cámara Anterior/fisiopatología , Extracción de Catarata , Complicaciones Posoperatorias , Uveítis Anterior/fisiopatología , Agudeza Visual/fisiología , Enfermedad Aguda , Administración Tópica , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Trastornos de Ansiedad/etiología , Trastornos de Ansiedad/fisiopatología , Betametasona/uso terapéutico , Femenino , Estudios de Seguimiento , Glucocorticoides/uso terapéutico , Humanos , Masculino , Persona de Mediana Edad , Midriáticos/uso terapéutico , Dolor Postoperatorio/etiología , Dolor Postoperatorio/fisiopatología , Estudios Prospectivos , Resultado del Tratamiento , Uveítis Anterior/tratamiento farmacológico , Uveítis Anterior/etiología , Trastornos de la Visión/etiología , Trastornos de la Visión/fisiopatología
20.
J Anim Physiol Anim Nutr (Berl) ; 91(1-2): 11-8, 2007 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17217386

RESUMEN

We have recently suggested that feeding the C18 polyunsaturated fatty acid, alpha-linolenic acid (ALA), instead of linoleic acid (LA) reduced body fat in mice. However, the difference in body fat did not reach statistical significance, which prompted us to carry out this study using more animals and diets with higher contents of ALA and LA so that the contrast would be greater. The diets contained either 12% (w/w) LA and 3% ALA or 12% ALA and 4% LA. A low-fat diet was used as control. The diets were fed for 35 days. The proportion of body fat was not influenced by the type of dietary fatty acid. Plasma total cholesterol and phospholipids were significantly lower in ALA-fed mice than in mice fed LA. Activities of enzymes in the fatty acid oxidation pathway were significantly raised by these two diets when compared with the control diet. alpha-Linolenic acid vs. LA did not affect fatty acid oxidation enzymes. In mice fed the diet with LA activities of enzymes of de novo fatty acid synthesis were significantly decreased when compared with mice fed the control diet. alpha-Linolenic acid vs. LA feeding did not influence lipogenic enzymes. It is concluded that feeding mice for 35 days with diets either rich in LA or ALA did not significantly influence body composition.


Asunto(s)
Composición Corporal/efectos de los fármacos , Ácido Linoleico/administración & dosificación , Hígado/enzimología , Ácido alfa-Linolénico/administración & dosificación , Animales , Colesterol/sangre , Relación Dosis-Respuesta a Droga , Ácido Linoleico/metabolismo , Lípidos/biosíntesis , Lipogénesis , Hígado/metabolismo , Masculino , Ratones , Ratones Endogámicos BALB C , Oxidación-Reducción , Fosfolípidos/sangre , Distribución Aleatoria , Destete , Ácido alfa-Linolénico/metabolismo
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