Comparison of acute responses to isotonic or isokinetic eccentric muscle action: differential outcomes in skeletal muscle damage and implications for rehabilitation.

Both isotonic and isokinetic eccentric muscle contractions are commonly used in muscle research laboratories to induce muscle damage, yet, the muscle damage outcomes between these 2 modes of eccentric contraction have not been compared. The purpose of this study was to compare modes of contraction for differences in muscle damage. 16 men were placed in the isotonic (IT: 110% of maximal isometric torque) or the isokinetic (IK: 120°/s) group, with each group performing 200 eccentric muscle actions of the knee extensors. Isometric peak torque, perceived soreness and CK activity were measured immediately pre and post exercise, and 48-h post exercise. Mean total work (~1700 J) and peak torque per set (~265 Nm) decreased over the 200 repetitions (p<0.01), and was not different between groups. Damage markers changed 48-h post exercise (p<0.05): peak isometric torque (-13%), creatine kinase activity (+200%) and self-perceived muscular soreness (+4 unit change). Significant group×time interactions (p<0.01) indicated that peak isometric torque was 22% lower, and creatine kinase and self-perceived muscular soreness were 330% and 3 unit difference higher in the IT as compared to the IK groups, 48-h post exercise. When equating for total work, skeletal muscle damage markers are higher during IT vs. IK modes. This reflects differences inherent in contraction type and suggests that this should be taken into account during physical rehabilitation.

Bacteriemias en la población de mayores de 80 años / Bloodstream infection in the up to 80 year-old-patients

Introducción. El objetivo de nuestro estudio fue describir las características de las bacteriemias detectadas en pacientes de más de 79 años, e identificar posibles factores relacionados con la mortalidad. Material y métodos. Estudio de cohortes, retrospectivo, en el que se incluye a todos los pacientes de más de 17 años de edad con bacteriemia detectada entre los años 2004-2007. Se recogieron variables demográficas, comorbilidades, foco de la bacteriemia, agente causante, gravedad y mortalidad intrahospitalaria. Los pacientes fueron clasificados en 3 franjas de edad: de 18 a 64 años (G1), de 65 a 79 (G2) y ≥80 años (G3). Resultados. Se analizaron 1.594 episodios de bacteriemia (35% en G1, 35% en G2 y 29% en G3). En el G3, el 47% presentó insuficiencia renal, el 83% neoplasia sólida, el 2% inmunosupresión, el 5% desnutrición y el 38% úlceras por decúbito. Estas proporciones fueron del 27, 30, 5, y 2%, respectivamente en G2, y del 15, 16, 12 y 5%, en G1 (p<0,01). El foco urinario representó el 28, 43 y 44% en G1, G2 y G3, respectivamente (p<0,01) y el biliar, 6, 11 y 16% (p<0,01). E. coli representó el 32% en G1, el 44% en G2 y el 51% en G3. La mortalidad en cada grupo de edad fue del 9, 16 y 21%. En el análisis multivariado, la mortalidad en los ≥80 años se relacionó con la insuficiencia renal, la desnutrición, la presencia de úlceras y el shock. Conclusiones. Las bacteriemias en el anciano son sobretodo de origen urinario. La mortalidad en estos casos depende sobre todo del estado basal del paciente y no tanto de su edad(AU)

Introduction. The aim of our study was to describe the characteristics of bacteremia detected in patients over 79 years and to identify possible factors associated with the mortality. Methods. A retrospective cohort study, which included all patients over 17 years of age with bacteremia detected between 2004-7 was performed. Demographic variables, comorbidities, source of bacteremia, causing microorganism, severity and hospital mortality were recorded. Patients were classified into three age groups: 18 to 64 years (G1), 65 to 79 (G2) and ≥80 years (G3). Results. We analyzed 1594 episodes of bacteremia (35% in G1, 35% in G2 and 29% in G3). In G3, 47% had renal failure, 83% solid neoplasm, 2% immunosuppression 5% malnutrition and 38% decubitus ulcers. These proportions were 27, 30, 5 and 2%, respectively in G2, and 15, 16, 12 and 5% in G1 (P<.01). The urinary focus accounted for 28%, 43% and 44% in G1, G2 and G3, respectively (P<.01) and biliary focus 6, 11 and 16% (P<.01), in each group. E. coli accounted for 32% in G1, 44% in G2 and 51% in G3. Mortality in each age group was 9, 16 and 21%. In multivariate analysis, mortality in the ≥80 years was associated with renal failure, malnutrition, the presence of ulcers and shock. Conclusions. Bacteremia in the elderly are mainly of urinary origin. Mortality in these cases depends primarily on the patient's baseline status rather than their age(AU)

[Bloodstream infection in the up to 80 year-old-patients]. / Bacteriemias en la población de mayores de 80 años.

INTRODUCTION: The aim of our study was to describe the characteristics of bacteremia detected in patients over 79 years and to identify possible factors associated with the mortality. METHODS: A retrospective cohort study, which included all patients over 17 years of age with bacteremia detected between 2004-7 was performed. Demographic variables, comorbidities, source of bacteremia, causing microorganism, severity and hospital mortality were recorded. Patients were classified into three age groups: 18 to 64 years (G1), 65 to 79 (G2) and ≥80 years (G3). RESULTS: We analyzed 1594 episodes of bacteremia (35% in G1, 35% in G2 and 29% in G3). In G3, 47% had renal failure, 83% solid neoplasm, 2% immunosuppression 5% malnutrition and 38% decubitus ulcers. These proportions were 27, 30, 5 and 2%, respectively in G2, and 15, 16, 12 and 5% in G1 (P<.01). The urinary focus accounted for 28%, 43% and 44% in G1, G2 and G3, respectively (P<.01) and biliary focus 6, 11 and 16% (P<.01), in each group. E. coli accounted for 32% in G1, 44% in G2 and 51% in G3. Mortality in each age group was 9, 16 and 21%. In multivariate analysis, mortality in the ≥80 years was associated with renal failure, malnutrition, the presence of ulcers and shock. CONCLUSIONS: Bacteremia in the elderly are mainly of urinary origin. Mortality in these cases depends primarily on the patient's baseline status rather than their age.

Complete mitochondrial DNA replacement in a Lake Tanganyika cichlid fish.

We used nuclear and mitochondrial DNA (mtDNA) sequences from specimens collected throughout Lake Tanganyika to clarify the evolutionary relationship between Lamprologus callipterus and Neolamprologus fasciatus. The nuclear data support the reciprocal monophyly of these two shell-breeding lamprologine cichlids. However, mtDNA sequences show that (i) L. callipterus includes two divergent and geographically disjunct (North-South) mtDNA lineages; and that (ii) N. fasciatus individuals cluster in a lineage sister group to the northern lineage of L. callipterus. The two mtDNA lineages of L. callipterus diverged c. 684 kya to 1.2 Ma, coinciding with a major water level low stand in Lake Tanganyika, which divided the lake into isolated sub-lakes. This suggests that the two mtDNA lineages originated as the result of the separation of L. callipterus populations in different sub-basins. The incongruent phylogenetic position of N. fasciatus can best be explained by an ancient unidirectional introgression from L. callipterus into N. fasciatus. Remarkably, our data indicate that this event resulted in the complete mtDNA replacement in N. fasciatus. Our data suggest that hybridization occurred soon after the divergence of the two L. callipterus mtDNA lineages, probably still during the water level low stand, and that subsequently the invading mtDNA lineage spread throughout the lake.

Relationship between growth hormone in vivo bioactivity, the insulin-like growth factor-I system and bone mineral density in young, physically fit men and women.

CONTEXT: Bone mineral density (BMD) is influenced by growth factors, such as growth hormone (GH) and insulin-like growth factor-I (IGF-I). The in vivo bioassay for GH (bioGH) provides a more physiologically relevant measurement than an in vitro immunoassay, since bioGH is quantified on a biological outcome. OBJECTIVE: To determine if bioGH and components of the IGF-I system were associated with BMD in age-matched men (M; n=41, 19.1+/-0.2 year, 70+/-3 kg, 163+/-25 cm) and women (W; n=39, 18.6+/-0.3 year, 66+/-3 kg, 141+/-15 cm). DESIGN: Blood was analyzed for growth-related hormones [bioGH, immunoreactive growth hormone (iGH), IGF-I and associated binding proteins], and BMD was measured by pDXA, pQCT, and central DXA (spine, hip). For the bioGH assay, hypophysectomizied female Sprague-Dawley rats were injected with a s.c. bolus of either a GH standard or unknown (each subject's plasma) in four daily injections. The tibia was then examined for epiphyseal growth plate width from which bioGH concentrations were extrapolated. RESULTS: M had greater (P<0.05) calcaneal BMD when measured by pDXA (M: 1.27+/-0.02; W: 1.14+/-0.02 g/cm2), while pQCT-assessed BMD at the tibia was not different (M: 777+/-16; W: 799+/-16 g/cm2). bioGH was similar between M (5388+/-800 microg/L) and W (4282+/-643 microg/L) and was not correlated with BMD. The only BMD-related biomarkers in women were acid-labile subunit (ALS; r=0.40) and IGFBP-3 (r=0.42) with DXA-measured spine and femoral neck BMD, and ALS (r=0.47) with pQCT-assessed tibial BMD and cortical thickness, respectively. CONCLUSION: Although bioGH was not associated with BMD, IGF-I and associated binding proteins (IGFBP-3 and ALS) emerged as correlates in W only.

Effects of intensified military field training on jumping performance.

A sensitive, reliable, field-expedient test may be valuable for monitoring interventions during periods of anticipated physical performance decline. The purpose of this study was to determine the capabilities of unloaded jumping tests for detecting decrements in physical performance following eight days of military sustained operations. Twenty-nine U. S. Marines (24 +/- 1 y; 180 +/- 6 cm; 82.5 +/- 8.2 kg) performed 1, 5 and 30 repetition(s) of unloaded countermovement jumps (UJ) before and after eight days of sustained operations (SUSOPS). Jump performance data was collected simultaneously using a switch mat (SM) and a linear position transducer (LPT). Jump height (m) and power (W) were highest using 1 UJ and declined 4.9 and 8.9%, respectively after SUSOPS. Jump power (JP) declined progressively over 30 UJ (20%). Five UJ offered no advantages over 1 UJ and was inadequate to examine changes in muscle fatigability (pre: 1294 +/- 138 W; post: 1250 +/- 165 W). The SM and a LPT were in agreement and had a high correlation (r = 0.92). One UJ was a sensitive, easy to implement test for monitoring the collective impact of high physical, nutritional, cognitive, and environmental stress on an individuals' physical performance before and after 8 days of SUSOPS, suggesting decrements in physical performance associated with overreaching can be detected by simply administered field-expedient jumping tests.

Optimal maintenance of constructed wetlands using an environmental decision support system.

Constructed wetlands (CWs) are artificial wastewater treatment systems appropriate for small communities because of their affordability, operability and reliability. These qualities are true whenever CWs are designed and constructed properly, and as long as the necessary operation and maintenance procedures are carried out correctly. Experience shows that the operation and maintenance procedures, and the frequencies with which these procedures are carried out, differ from one CW to another. With this in mind, and along with a projected increase in CWs in Catalonia, the Catalan Water Agency (Agència Catalana de l'Aigua) has developed an Environmental Decision Support System (EDSS) which proposes guidelines for monitoring and maintenance, according to the characteristics of each CW. This EDSS was developed following a methodology based on five steps: (i) problem analysis; (ii) collecting data and knowledge acquisition; (iii) model selection; (iv) model implementation and (v) validation. This paper describes the methodology followed to build the decision support system and presents some examples of the information provided by this EDSS.

Evaluating the application of a decision support system in identifying adequate wastewater treatment for small communities. A case study: the Fluvia River Basin.

The identification of adequate wastewater treatment for small communities is a complex problem since it demands a combination of data from different sources, such as aspects of the community and landscape, the receiving environment and the available wastewater treatment technologies. The Catalan Water Agency (Agència Catalana de l'Aigua) considered using an EDSS (Environmental Decision Support System) as a tool to help water managers select the most adequate treatment for the urban wastewater of nearly 3,500 small communities in Catalonia (Spain). From that moment, EDSS was applied to all the river basins in Catalonia. In this paper the authors present the results obtained for the 76 small communities located in one of these river basins: the Fluvia River Basin. The characteristics of the community used in the reasoning process of the EDSS, the list of selected wastewater treatment alternatives, the technical environmental justification for the selected treatments and the reasons for discarding, favouring or disadvantaging them are presented. Finally, some results for the Fluvia River Basin are compared with those obtained in other Catalan river basins with different characteristics in order to evaluate which are the significant features in identifying adequate wastewater treatments.

Development of a knowledge-based decision support system for identifying adequate wastewater treatment for small communities.

The identification of adequate treatment for small communities is a complex problem since it makes it necessary to combine aspects of the community and landscape, the receiving environment, and the available wastewater treatment technologies. This paper presents the development and implementation of a Knowledge-Based Decision Support System (KB-DSS) to tackle this problem. Different knowledge sources have been consulted in order to make up a comprehensive and accurate knowledge base. The core of the KB-DSS embraces two objectives. The first one is to assist in the selection of the treatment level adequate to fulfil the target quality standards for the receiving environment. The second one is to select the specific type of treatment. The KB-DSS is being applied to each one of the 3,482 different small communities comprised in the Small Communities Wastewater Treatment Plan of Catalonia, grouped according to river catchments. This paper also summarizes the different steps involved in the operation of the knowledge-based DSS when solving a real case study.