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1.
Rev Clin Esp (Barc) ; 224(1): 24-33, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38142975

RESUMEN

INTRODUCTION: In heart failure, cardiac rehabilitation has been recommended as an intervention strategy that improves functional capacity, health-related quality of life and survival. However, adherence to these programs is low. The objective was to determine the factors related to non-adherence to cardiac rehabilitation in patients with heart failure in Colombia. METHOD: Observational and retrospective study. Patients with heart failure were linked in a clinic in Colombia, adherence to cardiac rehabilitation was measured with ≥80% of scheduled sessions. Sociodemographic and clinical variables, functional aerobic capacity (Sit to Stand and 6-minute walk test), Duke Activity Status Index (DASI), quality of life Minnesota Living with Heart Failure Questionnaire (MLFHQ) and depression Patient health questionnaire 9 (PHQ-9) were taken into account. RESULTS: 300 patients were linked with heart failure with age 63.16 ± 12.87 men 194 (64.7%). adherence to cardiac rehabilitation was 66.67%, there were statistically significant differences between the groups in arterial hypertension, LVEF, cholesterol, LDL, Triglycerides, SBP, DBP, distance traveled, VO2e, METs, DASI and PHQ-9 p-value =<0.05. The logistic regression model adjusted for sex and age showed OR for non-adherence to CR arterial hypertension 2.23[1.22-4.07], LDL outside of goals 2.15[1.20-3.88], triglycerides outside goals 2.34[1.35-4.07], DASI<4METs 2.38 [1.04-5.45] and PHQ-9 1.06[1.00-1.12]. CONCLUSION: High blood pressure, LDL, triglycerides, DASI and depression with the PHQ-9 questionnaire are related factors for not having adherence to cardiac rehabilitation in patients with heart failure.


Asunto(s)
Rehabilitación Cardiaca , Insuficiencia Cardíaca , Hipertensión , Masculino , Humanos , Persona de Mediana Edad , Anciano , Calidad de Vida , Estudios Retrospectivos , Triglicéridos
3.
Eur J Obstet Gynecol Reprod Biol ; 274: 5-12, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35561567

RESUMEN

OBJECTIVES: Previous evidence seems to support the more common presence of certain pigmentation types in women with endometriosis. The aim of this study was to assess the association of certain somatic phenotypes with specific localizations of the disease. The genetic makeup of those somatic traits may will help in better define the disease pathogenesis. STUDY DESIGN: Multicentric, retrospective study of women aged 18 to 45 with histologically confirmed endometriosis. 575 patients were recruited at eleven different Italian endometriosis clinics from March 2015 to January 2021. Data regarding clinical and surgical features were recorded following the self-administered endometriosis patient questionnaire and the surgical standard of reports approved by the World Endometriosis Research Foundation (WERF). Pigmentation types/somatic phenotypes frequencies among endometriosis localizations were reported. A logistic regression analysis was performed to determine somatic types independently associated with disease' localizations. RESULTS: Having green eyes increased by ∼4 folds (OR 3.7; 95% CI: 1.42-9.61; p = 0.007) the risk of having a ureteral nodule, whereas brown/black eyes decreased this risk (OR 0.34; 95% CI: 0.13-0.87; p = 0.025). Consistently, the combination of green eyes and blonde/light brown hairs increased the odds of ureteral endometriosis by more than 5 folds (OR 5.40; 95%CI: 2.02-14.49; p = 0.001), even after correction for anthropometric confounders (aOR 5.85; 95% CI: 2.13-16.09; p < 0.001). CONCLUSIONS: The association between endometriosis and pigmentary traits has been herein confirmed, with the novel finding of the possible predisposition of ureteral endometriosis in patients with green eyes and blonde/light brown hairs. Further investigation on the genetic makeup of somatic traits may provide new inroads also into the molecular aspects of endometriosis leading to a better understanding of this complex disease.


Asunto(s)
Endometriosis , Endometriosis/complicaciones , Endometriosis/epidemiología , Endometriosis/genética , Color del Ojo , Femenino , Humanos , Fenotipo , Prevalencia , Estudios Retrospectivos
4.
Arch Gynecol Obstet ; 305(1): 149-157, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34623489

RESUMEN

PURPOSE: To evaluate obstetric outcome in women with endometriosis who conceive naturally and receive standard obstetric care in Italy. METHODS: Cases were consecutive women with endometriosis managed in eleven Italian referral centers. Controls were women in whom endometriosis was excluded. All women filled in a questionnaire addressing previous natural pregnancies. Marginal logistic regression models were fitted to evaluate the impact of endometriosis on obstetric outcome. A post hoc analysis was performed within the endometriosis group comparing women with severe adenomyosis versus women with absent or mild adenomyosis. RESULTS: Three hundred and fifty-five pregnancies in endometriosis group and 741 pregnancies in control group were included. Women with endometriosis had a higher risk of preterm delivery < 34 weeks (6.4% vs 2.8%, OR 2.42, 95% CI 1.22-4.82), preterm delivery < 37 weeks (17.8% vs 9.7%, OR 1.98, 95% CI 1.23-3.19), and neonatal admission to Intensive Care Unit (14.1% vs 7.0%, OR 2.04, 95% CI 1.23-3.36). At post hoc analysis, women with endometriosis and severe adenomyosis had an increased risk of placenta previa (23.1% vs 1.8%, OR 16.68, 95% CI 3.49-79.71), cesarean delivery (84.6% vs 38.9%, OR 8.03, 95% CI 1.69-38.25) and preterm delivery < 34 weeks (23.1% vs 5.7%, OR 5.52, 95% CI 1.38-22.09). CONCLUSION: Women with endometriosis who conceive naturally have increased risk of preterm delivery and neonatal admission to intensive care unit. When severe adenomyosis is coexistent with endometriosis, women may be at increased risk of placenta previa and cesarean delivery. TRIAL REGISTRATION: Clinical trial registration number: NCT03354793.


Asunto(s)
Adenomiosis , Endometriosis , Placenta Previa , Nacimiento Prematuro , Adenomiosis/complicaciones , Endometriosis/complicaciones , Endometriosis/epidemiología , Femenino , Humanos , Recién Nacido , Placenta Previa/epidemiología , Embarazo , Resultado del Embarazo/epidemiología , Nacimiento Prematuro/epidemiología , Nacimiento Prematuro/etiología , Estudios Retrospectivos
6.
J Electromyogr Kinesiol ; 56: 102485, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33186835

RESUMEN

Facial nerve paralysis (FNP) has a significant effect on a person's quality of life. In individuals with FNP undergoing facial rehabilitation, methods to analyze the loss of function are useful in diagnosis, treatment and follow up. To propose a protocol with kinematic analysis coupled with sEMG to evaluate the outcomes of FNP, quantifying the excursion degrees of the facial muscles and symmetry of voluntary movements. 10 patients (Group A) were followed by diagnosis until the end of the rehabilitation program. Kinematic analysis of 20 healthy adults (group B) was performed as a starting point to have a normality range and to test intra-subject and inter- intra rater reliability. An optoelectronic system and sEMG wireless electrodes were used. In Group A, a significant improvement in the movement of frontalis muscle (P = 0.0118) after 4-week treatment from the beginning (T0) 9.8 ± 4.5 mm to the end of rehabilitation (T1) 16.3 ± 5.8 mm and orbicularis oris (P = 0.0143) from T0 14.8 ± 5.5 mm to T1 20.3 ± 3.3 mm and, a reduction of % of maximum voluntary contractions (MVC) at T1 for frontalis and orbicularis compared to T0. This protocol provides meaningful data in a simple, reliable and objective way for the functional assessment of patients with PNF.


Asunto(s)
Fenómenos Biomecánicos/fisiología , Electromiografía/métodos , Músculos Faciales/fisiopatología , Parálisis Facial/fisiopatología , Movimiento/fisiología , Adulto , Nervio Facial/fisiopatología , Parálisis Facial/diagnóstico , Parálisis Facial/rehabilitación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Modalidades de Fisioterapia/tendencias , Calidad de Vida , Reproducibilidad de los Resultados , Adulto Joven
7.
J Int Med Res ; 48(8): 300060520948382, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32840156

RESUMEN

Rehabilitation is important for patients with coronavirus disease 2019 (COVID-19) infection. Given the lack of guidelines in English on the rehabilitation of these patients, we conducted a review of the most recent reports. We performed this literature review using the principal research databases and included randomized trials, recommendations, quasi-randomized or prospective controlled clinical trials, reports, guidelines, field updates, and letters to the editor. We identified 107 studies in the database search, among which 85 were excluded after screening the full text or abstract. In total, 22 studies were finally included. The complexity of the clinical setting and the speed of spread of the severe acute respiratory syndrome coronavirus 2, which leads to rapid occupation of beds in the intensive care unit, make it necessary to discharge patients with COVID-19 who have mild symptoms as soon as possible. For these reasons, it is necessary to formulate rehabilitation programs for these patients, to help them restore physical and respiratory function and to reduce anxiety and depression, particularly patients with comorbidities and those who live alone or in rural settings, to restore a good quality of life.


Asunto(s)
Infecciones por Coronavirus/psicología , Infecciones por Coronavirus/rehabilitación , Resumen del Alta del Paciente , Neumonía Viral/psicología , Neumonía Viral/rehabilitación , Ansiedad/psicología , Betacoronavirus , COVID-19 , Depresión/psicología , Humanos , Pandemias , Alta del Paciente , Calidad de Vida , SARS-CoV-2
8.
Climacteric ; 22(4): 329-338, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-30628469

RESUMEN

The incidence of endometriosis in middle-aged women is not minimal compared to that in the reproductive age group. The treatment of affected women after childbearing age to the natural transition toward menopause has received considerably poor attention. Disease management is problematic for these women due to increased contraindications regarding hormonal treatment and the possibility for malignant transformation, considering the increased cancer risk in patients with a long-standing history of the disease. This state-of-the-art review aims for the first time to assess the benefits of the available therapies to help guide treatment decisions for the care of endometriosis in women approaching menopause. Progestins are proven effective in reducing pain and should be preferred in these women. According to the international guidelines that lack precise recommendations, hysterectomy with bilateral salpingo-oophorectomy should be the definitive therapy in women who have completed their reproductive arc, if medical therapy has failed. Strict surveillance or surgery with removal of affected gonads should be considered in cases of long-standing or recurrent endometriomas, especially in the presence of modifications of ultrasonographic cyst patterns. Although rare, malignant transformation of various tissues in endometriosis patients has been described, and management is herein discussed.


Asunto(s)
Endometriosis/terapia , Menopausia , Toma de Decisiones Clínicas , Femenino , Humanos , Histerectomía , Ovariectomía , Salpingectomía
9.
Artículo en Inglés, Español | MEDLINE | ID: mdl-29784500

RESUMEN

OBJECTIVE: To evaluate whether postoperative continuous wound infiltration of levobupivacaine through two submuscular catheters connected to two elastomeric pumps after lumbar instrumented arthrodesis is more effective than intravenous patient-controlled analgesia. MATERIAL AND METHODS: An observational, prospective cohorts study was carried out. The visual analogue scale, the need for additional rescue analgesia and the onset of adverse effects were recorded. RESULTS: Pain records measured with visual analogue scale scale were significantly lower in the 48hours postoperative record at rest (p=.032). The other records of visual analogue scale showed a clear tendency to lower levels of pain in the group treated with the catheters. No statistically significant differences were found in the rescue analgesia demands of the patients. The adverse effects were lower in the catheter group (6 cases versus 11 cases) but without statistical differences. CONCLUSIONS: A trend to lower pain records was found in the group treated with catheters, although differences were not statistically significant.


Asunto(s)
Anestésicos Locales/administración & dosificación , Cateterismo/instrumentación , Catéteres , Levobupivacaína/administración & dosificación , Vértebras Lumbares/cirugía , Dolor Postoperatorio/tratamiento farmacológico , Fusión Vertebral , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Analgesia Controlada por el Paciente , Anestésicos Locales/uso terapéutico , Cateterismo/métodos , Femenino , Estudios de Seguimiento , Humanos , Infusiones Intralesiones , Levobupivacaína/uso terapéutico , Masculino , Persona de Mediana Edad , Dolor Postoperatorio/diagnóstico , Estudios Prospectivos , Adulto Joven
10.
Int J Tuberc Lung Dis ; 17(12): 1545-51, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24200266

RESUMEN

SETTING: Twenty hospitals in Spain. OBJECTIVE: To describe the incidence of active tuberculosis (TB) and factors related to TB development after treatment for latent tuberculous infection (TLTBI) in human immunodeficiency virus-1 (HIV-1) infected patients in the highly active antiretroviral therapy era. DESIGN: In a multicentre cohort of HIV-1-infected patients, we calculated TB incidence by tuberculin skin test (TST) results and TLTBI, and factors associated with a positive TST and the development of TB after TLTBI. RESULTS: Of 7902 patients, 6.5% had a history of TB at enrolment: 168 patients developed TB during 10,889 person-years (py) of follow-up, corresponding to an incidence rate of 1.54 cases per 100 py (95%CI 1.33-1.80). TB incidence in TST-positive patients who did not receive TLTBI was three times higher (6 cases/100 py) than in those who did (1.75 cases/100 py). In patients who received TLTBI, risk of development of TB was higher among cases aged <35 years (HR 6.14, 95%CI 1.12-33.73) and in those with a nadir CD4(+) cell count of <200 cells/µl (HR 5.64, 95%CI 1.34-23.70). CONCLUSIONS: TLTBI is effective in preventing the development of TB in HIV-infected patients, particularly in those who were TST-positive.


Asunto(s)
Antituberculosos/uso terapéutico , Coinfección , Infecciones por VIH/epidemiología , Tuberculosis Latente/tratamiento farmacológico , Tuberculosis Latente/epidemiología , Adulto , Recuento de Linfocito CD4 , Femenino , Infecciones por VIH/diagnóstico , Infecciones por VIH/virología , VIH-1/aislamiento & purificación , Humanos , Incidencia , Tuberculosis Latente/diagnóstico , Masculino , Valor Predictivo de las Pruebas , Estudios Prospectivos , España/epidemiología , Factores de Tiempo , Resultado del Tratamiento , Prueba de Tuberculina
11.
Exp Clin Endocrinol Diabetes ; 119(6): 348-52, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21264807

RESUMEN

OBJECTIVE: To evaluate the predictive value of disease free status of basal thyroglobulin (Tg) in differentiated thyroid carcinoma (DTC). DESIGN: Basal and recombinant human TSH (rhTSH) stimulated Tg measured with a commercial immunoassay (Liaison DiaSorin, Italial), neck ultrasonography (US) and fine needle aspiration cytology if required were performed in DTC patients followed prospectively for 6.8 years in a university hospital. 92 consecutive DTC patients were included. 74 patients with basal and stimulated Tg <1.0 ng/ml and Tg antibodies and US negative were considered as disease-free and persistent/recurrent disease was detected in 18 patients. In 25/74 disease-free patients rhTSH test was repeated within one year. RESULTS: 63/92 patients had undetectable basal Tg (<0.5 ng/ml), with rhTSH-Tg <0.5 ng/ml in 52, in 6 rhTSH-Tg between 0.5 and 1 ng/ml, in 2 between 1-2 ng/ml (disease-free after 3 years of follow-up) and >2.0 ng/ml (mean 4.1±2.4 ng/ml) in another 3, with US lymphatic metastasis confirmed histologically. Disease-free state was predicted with a sensitivity (S) of 66.7% and specificity (Sp) of 75.7% for basal Tg-0.5 ng/ml, and S 100% and Sp 85.1% for stimulated Tg-0.92. rhTSH test and US were repeated within one year in 25 disease-free patients with Tg<1.0 ng/ml. No further elevation below 1 ng/ml was observed. CONCLUSIONS: Low risk patients with undetectable basal Tg measured with current commercially available immunoassays should be followed with at least one rhTSH stimulated Tg and neck US because of the insufficient predictive value for recurrence/persistent disease of basal Tg.


Asunto(s)
Carcinoma/diagnóstico , Técnicas de Diagnóstico Endocrino/estadística & datos numéricos , Tiroglobulina/sangre , Neoplasias de la Tiroides/diagnóstico , Tirotropina , Adulto , Anciano , Carcinoma/sangre , Técnicas de Diagnóstico Endocrino/normas , Femenino , Estudios de Seguimiento , Humanos , Inmunoensayo/métodos , Inmunoensayo/normas , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Proteínas Recombinantes/análisis , Valores de Referencia , Sensibilidad y Especificidad , Tiroglobulina/análisis , Neoplasias de la Tiroides/sangre , Tirotropina/análisis , Tirotropina/sangre
12.
J Chem Phys ; 133(18): 184304, 2010 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-21073220

RESUMEN

Transition states and reaction paths for a hydrogen molecule dissociating on small aluminum clusters have been calculated using density functional theory. The two lowest spin states have been taken into account for all the Al(n) clusters considered, with n=2-6. The aluminum dimer, which shows a (3)Π(u) electronic ground state, has also been studied at the coupled cluster and configuration interaction level for comparison and to check the accuracy of single determinant calculations in this special case, where two degenerate configurations should be taken into account. The calculated reaction barriers give an explanation of the experimentally observed reactivity of hydrogen on Al clusters of different size [Cox et al., J. Chem. Phys. 84, 4651 (1986)] and reproduce the high observed reactivity of the Al(6) cluster. The electronic structure of the Al(n)-H(2) systems was also systematically investigated in order to determine the role played by interactions of specific molecular orbitals for different nuclear arrangements. Singlet Al(n) clusters (with n even) exhibit the lowest barriers to H(2) dissociation because their highest doubly occupied molecular orbitals allow for a more favorable interaction with the antibonding σ(u) molecular orbital of H(2).


Asunto(s)
Aluminio/química , Hidrógeno/química , Dimerización , Teoría Cuántica
14.
Rev Chilena Infectol ; 24(2): 137-41, 2007 Apr.
Artículo en Español | MEDLINE | ID: mdl-17453072

RESUMEN

The resistance of Acinetobacter baumannii to ss-lactam antibiotics is mainly due to the synthesis of ss-lactamases. From a clinical point of view, this bacteria and others, grouped under the acronym SPACE (S: Serratia, P: Pseudomonas, A: Acinetobacter, C: Citrobacter, E: Enterobacter) are essentially Amp-C ss-lactamases producers. There is no local information about ESBL presence in Acinetobacter. We studied ESBL production using the Ho and col. technique modified by adding cloxacillin as chromosomal ss-lactamases inhibitor. From 69 isolates, with resistance to at least one third generation cephalosporin, only 7 showed positive synergy test. Four of these amplified for TEM family gene, and one of these amplified also for the OXA family. Our study found a low ESBL production percentage, which agrees with the premise of Amp-C as the main mechanism of resistance to ss-lactam antibiotics in A. baumannii. However, the ESBL description in these bacteria emphasizes the capacity of expressing multiple resistance mechanisms.


Asunto(s)
Acinetobacter baumannii/enzimología , Antibacterianos/farmacología , Proteínas Bacterianas/biosíntesis , Resistencia betalactámica , beta-Lactamasas/biosíntesis , Acinetobacter baumannii/efectos de los fármacos , Acinetobacter baumannii/aislamiento & purificación , Chile , Farmacorresistencia Bacteriana , Humanos , Focalización Isoeléctrica , Pruebas de Sensibilidad Microbiana
15.
Rev. chil. infectol ; Rev. chil. infectol;24(2): 137-141, abr. 2007. tab
Artículo en Español | LILACS | ID: lil-471964

RESUMEN

The resistance of Acinetobacter baumannii to ß-lactam antibiotics is mainly due to the synthesis of ß-lactamases. From a clinical point of view, this bacteria and others, grouped under the acronym SPACE (S: Serratia, P: Pseudomonas, A: Acinetobacter, C: Citrobacter, E: Enterobacter) are essentially Amp-C ß-lactamases producers. There is no local information about ESBL presence in Acinetobacter. We studied ESBL production using the Ho and col. technique modified by adding cloxacillin as chromosomal ß-lactamases inhibitor. From 69 isolates, with resistance to at least one third generation cephalosporin, only 7 showed positive synergy test. Four of these amplified for TEM family gene, and one of these amplified also for the OXA family. Our study found a low ESBL production percentage, which agrees with the premise of Amp-C as the main mechanism of resistance to ß-lactam antibiotics in A. baumannii. However, the ESBL description in these bacteria emphasizes the capacity of expressing multiple resistance mechanisms.


La resistencia de Acinetobacter baumannii a antimicrobianos ß-lactámicos se debe fundamentalmente a la síntesis de ß-lactamasas. Del punto de vista clínico se considera que esta bacteria, y otras agrupadas en el acrónimo SPACE (Serratia, Pseudomonas, Acinetobacter, Citrobacter, Enterobacter), son predominantemente productoras de ß-lactamasas tipo AmpC. No hay información en nuestro país sobre presencia de ß-lactamasas de espectro extendido (BLEE) en Acinetobacter. Se estudió la producción de BLEE en cepas de Acinetobacter, mediante una modificación de la técnica de Ho y col adicionando cloxacilina como inhibidor de ß-lactamasas cromosomales. De 69 cepas con resistencia al menos a una cefalosporina de tercera generación, sólo siete presentaron sinergia positiva. Cuatro cepas amplificaron por RPC un fragmento intragénico de genes de familia TEM y una de ellas amplificó, además, para el gen de la familia OXA. Se evidenció un bajo porcentaje de producción de BLEE, lo que confirma que la producción de Amp-C es el principal mecanismo de resistencia de A. baumannii a ß-lactámicos. Sin embargo, la descripción de BLEE en esta bacteria, enfatiza su capacidad de albergar múltiples mecanismos de resistencia.


Asunto(s)
Humanos , Acinetobacter baumannii/enzimología , Antibacterianos/farmacología , Resistencia betalactámica , Proteínas Bacterianas/biosíntesis , beta-Lactamasas/biosíntesis , Acinetobacter baumannii/efectos de los fármacos , Acinetobacter baumannii/aislamiento & purificación , Chile , Farmacorresistencia Bacteriana , Focalización Isoeléctrica , Pruebas de Sensibilidad Microbiana
16.
J Phys Chem A ; 109(19): 4252-60, 2005 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-16833753

RESUMEN

The ab initio calculation of the interaction forces between the LiH+ molecular ion, at its equilibrium geometry, and several He atoms is carried out in order to isolate and assess the importance of many-body contributions in the search for realistic energy and geometry data. The full potential energy surface (PES) with a single helium partner is obtained first by using an aug-cc-pVQZ basis set for He and higher quality ones for Li and H. The calculations were performed at the CAS-SCF plus MRCI level for the lowest potential energy surface over a total of 480 grid points of the two intermolecular Jacobi coordinates, whereas the excited state surface has also been examined in order to exclude the presence of any significant nonadiabatic interaction between the two PESs. A numerical fit of the lower surface is presented and the general physical changes of the ionic interaction when going from the lower to the upper of the two potentials are described and discussed. The fairly limited importance of many-body effects for such systems is seen from further ab initio calculations including several He atoms: our results suggest that, at least in the present case, no strong charge migration occurs after He attachment, and therefore, one could realistically model larger clusters by implementing a sum-of-potentials approach via the presently computed PES.

17.
Appl Radiat Isot ; 60(5): 759-66, 2004 May.
Artículo en Inglés | MEDLINE | ID: mdl-15082056

RESUMEN

Intensification of agricultural production in south-central Chile since the 1970s has caused problems of increased soil erosion and associated soil degradation. These problems have prompted a shift from conventional tillage to no-till management practices. Faced with the need to establish the impact of this shift in soil management on rates of soil loss, the use of caesium-137 (137Cs) measurements has been explored. A novel procedure for using measurements of the 137Cs depth distribution to estimate rates of soil loss at a sampling point under the original conventional tillage and after the shift to no-till management has been developed. This procedure has been successfully applied to a study site at Buenos Aires farm near Carahue in the 9th region of Chile. The results obtained indicate that the shift from conventional tillage to no-till management has caused net rates of soil loss to decrease to about 40% of those existing under conventional tillage. This assessment of the impact of introducing no-till management at the study site must, however, be seen as provisional, since only a limited number of sampling points were used. A simplified procedure aimed at documenting the reduction in erosion rates at additional sampling points, based solely on measurements of the 137Cs inventory of bulk cores and the 137Cs activity in the upper part of the soil has been developed and successfully tested at the study site. Previous application of 137Cs measurements to estimate erosion rates has been limited to estimation of medium-term erosion rates during the period extending from the beginning of fallout receipt to the time of sampling. The procedures described in this paper, which permits estimation of the change in erosion rates associated with a shift in land management practices, must be seen as representing a novel application of 137Cs measurements in soil erosion investigations.


Asunto(s)
Agricultura/métodos , Radioisótopos de Cesio/análisis , Suelo/análisis , Conservación de los Recursos Naturales , Ceniza Radiactiva , Contaminantes Radiactivos del Suelo/análisis
18.
Lab Invest ; 81(12): 1627-38, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11742033

RESUMEN

Pulmonary neuroendocrine (NE) cells are found as clusters called neuroepithelial bodies (NEBs) or as single cells scattered in the respiratory epithelium. They express a variety of bioactive peptides, and they are thought to be the origin of NE lung tumors. Proadrenomedullin N-terminal 20 peptide (PAMP) is a peptide derived from the same precursor as adrenomedullin (AM). AM and PAMP are C-terminally amidated during their processing by a well-characterized amidating enzyme, peptidylglycine alpha-amidating monooxygenase (PAM). We explored AM, PAMP, and PAM expression as markers for NE hyperplasia in three rodent species (Fischer 344 rats, Syrian golden hamsters, and A/J mice) after a single intratracheal instillation of crystalline silica (quartz), which was previously found to induce different reactions in the three species. Rats developed a marked silicosis, with alveolar and bronchiolar hyperplasia and formation of peripheral lung epithelial tumors. Mice developed a moderate degree of silicosis, but not epithelial hyperplasia or tumors. Hamsters showed dust-storage lesions, but not silicosis or tumors. NE cells were immunolabeled for calcitonin gene-related peptide (CGRP), AM, PAMP, and PAM in serial sections of each lung. The numbers of positive NEBs per lung area and positive cells per NEB were quantified. A marked hyperplastic reaction in the NEBs of silica treated rats occurred only in alveolar NEBs, but not in bronchiolar NEBs. From Month 11 onwards, there were marked differences in the number of alveolar NEBs per section and in the number of cells per alveolar NEB immunoreactive for CGRP. No hyperplastic NE cell reaction was observed in silica-treated mice and hamsters. Significant PAMP and PAM expression was seen only in rat hyperplastic alveolar and in bronchiolar NEBs from Month 11 onwards. In E18, rat fetal lung NEBs were found to be strongly positive for PAMP and PAM.


Asunto(s)
Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Sistemas Neurosecretores/patología , Alveolos Pulmonares/patología , Adrenomedulina , Amidas/metabolismo , Animales , División Celular , Cricetinae , Enzimas/metabolismo , Femenino , Feto/metabolismo , Hiperplasia , Neoplasias Pulmonares/inducido químicamente , Mesocricetus , Ratones , Ratones Endogámicos , Sistemas Neurosecretores/embriología , Sistemas Neurosecretores/metabolismo , Fragmentos de Péptidos/metabolismo , Péptidos/metabolismo , Precursores de Proteínas/metabolismo , Proteínas/metabolismo , Alveolos Pulmonares/embriología , Ratas , Ratas Endogámicas F344 , Valores de Referencia , Dióxido de Silicio
19.
Rev. méd. Chile ; 128(8): 863-7, ago. 2000. tab
Artículo en Español | LILACS | ID: lil-270908

RESUMEN

Background: Acinetobacter baumannii is an important etiological agent causing nosocomial infections. High level of resistance for different kind of antimicrobials has been observed, including ß-lactam antibiotics. This feature, chromosomal or plasmid encoded, has been associated to integrons harbouring antibiotic resistance gene cassettes. Aims: To investigate the presence of integrons among clinical isolates resistant to third generation cephalosporins (3GC). Material and methods: One hundred A. baumannii strains isolated from several Chilean hospitals were included in this study. Minimal inhibitory concentrations (MIC) of 3GC by an agar dilution method were carried out. Integrons class 1, 2 and 3 were investigated by colony blot hybridisation and confirmed by PCR. Results: High level of resistance to all assayed 3GC was observed. On the other hand, integrón class 2 was the most prevalent (77 percent of isolates) followed by integron class 1 (52 percent). Forty six percent of isolates hybridised with probes for both of them. However, no positive hybridisation was detected for integron class 3. Conclusions: Nevertheless, most isolates harboured one or both class of integron; there was no direct relationship between the presence of these genetic structures and the resistance to this kind of ß-lactam antibiotics


Asunto(s)
Humanos , Acinetobacter/genética , Farmacorresistencia Microbiana/genética , Resistencia a las Cefalosporinas/genética , Técnicas In Vitro , Acinetobacter/aislamiento & purificación , Acinetobacter/efectos de los fármacos , Acinetobacter/patogenicidad , Elementos Transponibles de ADN/efectos de los fármacos , Infección Hospitalaria/microbiología , Oligonucleótidos
20.
Protein Sci ; 9(4): 820-6, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10794425

RESUMEN

We have used differential scanning calorimetry to determine the effect of low concentrations (C = 0-2 M) of the osmolyte sarcosine on the Gibbs energy changes (deltaG) for the unfolding of hen-egg-white lysozyme, ribonuclease A, and ubiquitin, under the same buffer and pH conditions. We have also computed this effect on the basis of the additivity assumption and using published values of the transfer Gibbs energies for the amino acid side chains and the peptide backbone unit. The values thus predicted for the slope delta deltaG/deltaC agree with the experimental ones, but only if the unfolded state is assumed to be compact (that is, if the accessibility to solvent of the unfolded state is modeled using segments excised from native structures). The additivity-based calculations predict similar delta deltaG/deltaC values for the three proteins studied. We point out that, to the extent that this approximate constancy of delta deltaG/deltaC holds, osmolyte-induced increases in denaturation temperature will be larger for proteins with low unfolding enthalpy (small proteins that bury a large proportion of apolar surface). The experimental results reported here are consistent with this hypothesis.


Asunto(s)
Proteínas/química , Sarcosina/química , Rastreo Diferencial de Calorimetría , Termodinámica
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