M(C6H16N3)2(VO3)4 as heterogeneous catalysts. Study of three new hybrid vanadates of cobalt(II), nickel(II) and copper(II) with 1-(2-aminoethyl)piperazonium.

Three new hybrid vanadates have been synthesized under hydrothermal conditions with the formula M(C(6)H(16)N(3))(2)(VO(3))(4), where M = Co(II), Ni(II) and Cu(II). The structural analyses show that the phases are isostructural and crystallize in the monoclinic space group P2(1)/c. These compounds show a two-dimensional crystal structure, with sheets composed of [VO(3)](n)(n-) chains and metal centres octahedrally coordinated, chelated by two 1-(2-aminoethyl)piperazonium ligands. The thermal study reveals that the copper containing phase is less stable than the cobalt and nickel containing ones. The IR spectra of the three phases are very similar, with little differences in the inorganic bond region of the copper containing phase. The UV-visible spectra show that the cobalt(II) and the nickel(II) are in slightly distorted octahedral environments. The catalytic tests show that the phases act as heterogeneous catalysts for the selective oxidation of alkyl aryl sulfides, with both H(2)O(2) and tert-butylhydroperoxide as oxidizing agents. The influence of the steric hindrance in the kinetic profile has been studied. The catalytic reactions induce the partial amorphization of the phases.

Prolonged interleukin-6 administration enhances glucose tolerance and increases skeletal muscle PPARalpha and UCP2 expression in rats.

Chronic elevations in interleukin (IL)-6 have been associated with insulin resistance, but acute IL-6 administration can enhance insulin sensitivity. Our aim was to exogenously administer IL-6 to rats to elicit either chronic or repeated acute elevations in systemic IL-6. We hypothesized that a continuous elevation of IL-6 would inhibit glucose tolerance and insulin sensitivity while acute intermittent elevations would improve it. Male Wistar rats were treated for 14d with recombinant human IL-6 (2.4 microy) or saline administered either by miniosmotic pump (continuous IL-6) or via twice-daily injection (intermittent IL-6). Glucose and insulin tolerance tests were performed following 14-d treatment and 24 h later rats were administered a bolus of insulin (150 mU/g) or saline intraperitoneally. Approximately, 10 min after insulin injection soleus, gastrocnemius and liver were excised and rapidly frozen in liquid nitrogen for subsequent metabolic measures. Irrespective of the mode of delivery, IL-6 treatment increased basal insulin sensitivity, as measured by the homeostatic model assessment of insulin resistance, and enhanced glucose clearance during an i.p. glucose tolerance test. IL-6 increased circulating fatty acids, but did not increase triglyceride accumulation in either skeletal muscle or liver, while it increased the protein expression of both PPARalpha and UCP2 in skeletal muscle, suggesting that IL-6 can enhance fat oxidation via mitochondrial uncoupling. These data demonstrate that, irrespective of the mode of delivery, IL-6 administration over 2 weeks enhances glucose tolerance. Our results do not support the notion that prolonged chronically elevated IL-6 impairs insulin action in vivo.

HSP72 protects against obesity-induced insulin resistance.

Patients with type 2 diabetes have reduced gene expression of heat shock protein (HSP) 72, which correlates with reduced insulin sensitivity. Heat therapy, which activates HSP72, improves clinical parameters in these patients. Activation of several inflammatory signaling proteins such as c-jun amino terminal kinase (JNK), inhibitor of kappaB kinase, and tumor necrosis factor-alpha, can induce insulin resistance, but HSP 72 can block the induction of these molecules in vitro. Accordingly, we examined whether activation of HSP72 can protect against the development of insulin resistance. First, we show that obese, insulin resistant humans have reduced HSP72 protein expression and increased JNK phosphorylation in skeletal muscle. We next used heat shock therapy, transgenic overexpression, and pharmacologic means to overexpress HSP72 either specifically in skeletal muscle or globally in mice. Herein, we show that regardless of the means used to achieve an elevation in HSP72 protein, protection against diet- or obesity-induced hyperglycemia, hyperinsulinemia, glucose intolerance, and insulin resistance was observed. This protection was tightly associated with the prevention of JNK phosphorylation. These findings identify an essential role for HSP72 in blocking inflammation and preventing insulin resistance in the context of genetic obesity or high-fat feeding.

Sistema de acceso subcutáneo vascular central permanente con reservorio en pacientes oncológicos. Complicaciones quirúrgicas / Permanent central venous subcutaneous access devices with reservoir in oncological patients. Surgical complications

Se realizó un estudio retrospectivo con el objetivo de determinar las complicaciones quirúrgicas en 60 pacientes consecutivos a los que se implantaron sistemas de accesos subcutáneos venosos centrales en nuestra institución (Port-a-Cath®), teniendo en cuenta edad, sexo, enfermedad oncológica y vasos abordados. Se registró 8,33 por ciento de complicaciones atribuibles a cirugía: hematomas posoperatorios, necrosis del bolsillo quirúrgico, mala posición del catéter en el vaso venoso y pérdida de derecho a domicilio del bolsillo quirúrgico. Nuestro estudio muestra que la mortalidad en el procedimiento quirúrgico para colocar sistemas de accesos subcutáneos vasculares centrales es nula y que las complicaciones quirúrgicas son pocas(AU)

A retrospective study was made to determine surgical complications in 60 consecutive patients in whom central subcutaneous venous access devices were implanted in our institution (Port­a-Carth®), taking age, sex, oncological disease and approached vessels into consideration. Surgery-attributable complications amounted to 8,33 per cent: postoperative hematomes, surgical pocket necrosis, wrong placement of catheter in the vein and loss of place of the surgical pocket. Our study showed that mortality in this surgical procedure for placing central venous access devices was nule and that surgical complications were few(AU)

[Lipid and metabolic profiles in adolescents are affected more by physical fitness than physical activity (AVENA study)]. / El perfil lipídico-metabólico en los adolescentes está más influido por la condición física que por la actividad física (estudio AVENA).

INTRODUCTION AND OBJECTIVES: To determine whether the level of physical activity or physical fitness (i.e., aerobic capacity and muscle strength) in Spanish adolescents influences lipid and metabolic profiles. METHODS: From a total of 2859 Spanish adolescents (age 13.0-18.5 years) taking part in the AVENA (Alimentación y Valoración del Estado Nutricional en Adolescentes) study, 460 (248 male, 212 female) were randomly selected for blood analysis. Their level of physical activity was determined by questionnaire. Aerobic capacity was assessed using the Course-Navette test. Muscle strength was evaluated using manual dynamometry, the long jump test, and the flexed arm hang test. A lipid-metabolic cardiovascular risk index was derived from the levels of triglycerides, low-density lipoprotein cholesterol (LDLC), high-density lipoprotein cholesterol (HDLC), and glucose. RESULTS: No relationship was found between the level of physical activity and lipid-metabolic index in either sex. In contrast, there was an inverse relationship between the lipid-metabolic index and aerobic capacity in males (P=.003) after adjustment for physical activity level and muscle strength. In females, a favorable lipid-metabolic index was associated with greater muscle strength (P=.048) after adjustment for aerobic capacity. CONCLUSIONS: These results indicate that, in adolescents, physical fitness, and not physical activity, is related to lipid and metabolic cardiovascular risk. Higher aerobic capacity in males and greater muscle strength in females were associated with lower lipid and metabolic risk factors for cardiovascular disease.

Structural, thermal, spectroscopic, specific-heat, and magnetic studies of (C5H18N3)[Fe3(HPO3)6].3H2O: a new organically templated iron(III) phosphite with a pillared structure formed by the interpenetration of two subnets.

A new open framework iron(III) phosphite with formula (C5H18N3)[Fe3(HPO3)6].3H2O has been prepared by hydrothermal synthesis with N-(2-aminoethyl)-1,3-propanediamine as a templating agent. The crystal structure was solved from single-crystal X-ray diffraction data in the trigonal space group R. The unit cell parameters are a= 8.803(1) A and c= 25.292(2) A with Z = 3. The complex pillared structure can be described as two interpenetrating subnets, one organic, [(C5H18N3).3H2O]3+, and one inorganic, [Fe3(HPO3)6]3-. In the inorganic subnet, the pillars are formed by FeO6 trimers linked by vertex sharing phosphite groups, while in the cationic subnet the organic molecules act like pillars. With increasing temperature, the flexibility of the structure allows contraction due to dehydration followed by thermal expansion before reaching the thermal stability limit. The Dq and Racah parameters calculated for (C5H18N3)[Fe3(HPO3)6].3H2O are Dq = 965, B = 1080, and C = 2472 cm(-1). Mössbauer spectroscopy confirms the trivalent oxidation state of iron cations and the crystallographic multiplicities of their sites. The ESR spectra show isotropic signals with a g-value of 2.00(1). Specific-heat measurements show a three-dimensional (lambda-type) peak at a critical temperature Tc = 32 K. The value of the entropy at saturation is 46 J/mol K, very near the expected value of 44.7 J/mol K for the iron(III) cations with S = 5/2. Magnetic measurements indicate a three-dimensional antiferromagnetic ordering below 32 K and a reorientation of spins below 15 K with an incomplete cancellation of spins due to triangular interactions inherent to the structure.

Parametrization of the magnetic behavior of the triangular spin ladder chains organically templated: (C2N2H10)[M(HPO3)F3] (M(III) = Fe, Cr, and V). Crystal structure and thermal and spectroscopic properties of the iron(III) phase.

A new iron(III) phosphite templated by ethylenediamine has been synthesized using solvothermal conditions under autogenous pressure. The (C2N2H10)[Fe(HPO3)F3] compound has been characterized by single-crystal X-ray diffraction data and spectroscopic and magnetic techniques. The crystal structure is formed by chains extended along the c axis and surrounded by ethylenediammonium cations. A study by diffuse-reflectance spectroscopy has been performed, and the calculated Dq, B, and C parameters for the Fe(III) cations are 1030, 720, and 3080 cm(-1), respectively. The Mössbauer spectrum at room temperature is characteristic of Fe(III) ions. The electron spin resonance (ESR) spectra carried out at different temperatures show isotropic signals with a g value of 2.00(1). The thermal evolution of the intensity of the ESR signals indicates the existence of antiferromagnetic interactions for the Fe(III) phase. The magnetic susceptibility data of the Cr(III) and V(III) compounds show antiferromagnetic couplings. The J-exchange parameters of the Fe(III) and Cr(III) compounds have been calculated by using a model for a triangular spin ladder chain. The values are J1 = -1.63(1) K and J2 = -0.87(2) K with g = 2.02 for the Fe(III) phase and J(1) = -0.56(2) K and J2 = -0.40(2) K with g = 1.99 for the Cr(III) compound. In the case of the V(III) phase, the fit has been performed considering a linear chain with the magnetic parameters D = 2.5 cm(-1) and J = -1.15(1) K.

Reduced plasma FFA availability increases net triacylglycerol degradation, but not GPAT or HSL activity, in human skeletal muscle.

Intramuscular triacylglycerols (IMTG) are proposed to be an important metabolic substrate for contracting muscle, although this remains controversial. To test the hypothesis that reduced plasma free fatty acid (FFA) availability would increase IMTG degradation during exercise, seven active men cycled for 180 min at 60% peak pulmonary O(2) uptake either without (CON) or with (NA) prior ingestion of nicotinic acid to suppress adipose tissue lipolysis. Skeletal muscle and adipose tissue biopsy samples were obtained before and at 90 and 180 min of exercise. NA ingestion decreased (P < 0.05) plasma FFA at rest and completely suppressed the exercise-induced increase in plasma FFA (180 min: CON, 1.42 +/- 0.07; NA, 0.10 +/- 0.01 mM). The decreased plasma FFA during NA was associated with decreased (P < 0.05) adipose tissue hormone-sensitive lipase (HSL) activity (CON: 13.9 +/- 2.5, NA: 9.1 +/- 3.0 nmol.min(-1).mg protein(-1)). NA ingestion resulted in decreased whole body fat oxidation and increased carbohydrate oxidation. Despite the decreased whole body fat oxidation, net IMTG degradation was greater in NA compared with CON (net change: CON, 2.3 +/- 0.8; NA, 6.3 +/- 1.2 mmol/kg dry mass). The increased IMTG degradation did not appear to be due to reduced fatty acid esterification, because glycerol 3-phosphate activity was not different between trials and was unaffected by exercise (rest: 0.21 +/- 0.07; 180 min: 0.17 +/- 0.04 nmol.min(-1).mg protein(-1)). HSL activity was not increased from resting rates during exercise in either trial despite elevated plasma epinephrine, decreased plasma insulin, and increased ERK1/2 phosphorylation. AMP-activated protein kinase (AMPK)alpha1 activity was not affected by exercise or NA, whereas AMPKalpha2 activity was increased (P < 0.05) from rest during exercise in NA and was greater (P < 0.05) than in CON at 180 min. These data suggest that plasma FFA availability is an important mediator of net IMTG degradation, and in the absence of plasma FFA, IMTG degradation cannot maintain total fat oxidation. These changes in IMTG degradation appear to disassociate, however, from the activity of the key enzymes responsible for synthesis and degradation of this substrate.

Fe(AsO4): a new iron(III) arsenate synthesized from thermal treatment of (NH4)[Fe(AsO4)F].

The new orthorhombic Fe(AsO4) phase has been synthesized by thermal treatment at 525 degrees C of a new (NH4)[Fe(AsO4)F] compound, with a [Fe(AsO4)F]- skeleton showing channels where the ammonium cations are located. The crystal structure of Fe(AsO4) has been solved from single-crystal data. The structure is formed by layers of edge-sharing dimeric octahedra, and interconnected by chains of alternating FeO6 octahedra and AsO4 tetrahedra.

Oral creatine supplementation and skeletal muscle metabolism in physical exercise.

Creatine is the object of growing interest in the scientific literature. This is because of the widespread use of creatine by athletes, on the one hand, and to some promising results regarding its therapeutic potential in neuromuscular disease on the other. In fact, since the late 1900s, many studies have examined the effects of creatine supplementation on exercise performance. This article reviews the literature on creatine supplementation as an ergogenic aid, including some basic aspects relating to its metabolism, pharmacokinetics and side effects. The use of creatine supplements to increase muscle creatine content above approximately 20 mmol/kg dry muscle mass leads to improvements in high-intensity, intermittent high-intensity and even endurance exercise (mainly in nonweightbearing endurance activities). An effective supplementation scheme is a dosage of 20 g/day for 4-6 days, and 5 g/day thereafter. Based on recent pharmacokinetic data, new regimens of creatine supplementation could be used. Although there are opinion statements suggesting that creatine supplementation may be implicated in carcinogenesis, data to prove this effect are lacking, and indeed, several studies showing anticarcinogenic effects of creatine and its analogues have been published. There is a shortage of scientific evidence concerning the adverse effects following creatine supplementation in healthy individuals even with long-term dosage. Therefore, creatine may be considered as a widespread, effective and safe ergogenic aid.

Hand size influences optimal grip span in women but not in men.

This study investigates which position (grip span) on the standard grip dynamometer results in maximum grip strength. Our null hypotheses included (1) no optimal grip span exists for measuring grip strength and (2) optimal grip span is unrelated to hand size. We also intended to derive a simple mathematical algorithm to adapt grip span to hand size. Seventy healthy subjects (40 women/30 men; mean age, 40 years; range; 20-80 years) free of upper-limb lesions were evaluated. Each hand was randomly tested on 10 occasions using 5 different grip spans. Our findings showed that (1) optimal grip span was identified for both genders and (2) hand size and optimal grip span correlated in women but not in men. When measuring handgrip strength in women, hand size must be taken into consideration. We provide a mathematical equation (y = x/5 + 1.5 cm) to adapt optimal grip span (y) to hand size (x) in women. In adult men, optimal grip span can be set at a fixed value (5.5 cm).

Técnica triangular rotatoria para la reconstrucción del párpado inferior / Rotating triangular technique for lower eyelid reconstruction

Cuando existen criterios para la exéresis del párpado inferior por invasión tumoral, el cirujano se da a la tarea de realizarla. Se realizó la selección de pacientes los cuales habían sido diagnosticados como portadores de carcinomas baso celulares en el párpado inferior, los cuales debían ser sometidos a intervenciones en las cuales requerían de una exéresis total del párpado inferior. Es una técnica para la reconstrucción del párpado inferior con aceptables resultados estéticos y funcionales.

Cirugía tiroidea: principios anatómicos y técnicos para reducir complicaciones / Thyroid surgery: anatomical and technical principles to reduce complications

La cirugía tiroidea se basa en los modernos conocimientos anatómicos y principios técnicos que permiten reducir sus complicaciones. Con el fin de ilustrar las ventajas de una estrategia quirúrgica específica, se muestran los resultados en 503 enfermos operados por nódulos tiroideos entre 1992 y 1996 (ambos incluidos) por un cirujano. En todos se empleó una técnica reglada y segura basada en las peculiaridades anatómicas de los nervios laríngeos, las glándulas paratiroides y los medios de fijación del tiroides. En 88 pacientes (17,5 porciento) había un cáncer tiroideo. Se hicieron 317 hemitiroidectomías (63 porciento), 133 tiroidectomías totales (26,4 porciento), 30 istmectomías (6,0 porciento), y 12 tiroidectomías casi totales (2,4 porciento); en otros 11 enfermos se realizó tiroidectomía total, más linfadenectomía cervical. En 13 pacientes se encontró alguna variante anatómica. Sólo ocurrió una lesión recurrencial y un hipoparatiroidismo permanente (0,2 porciento en cada caso)

Timomas: correlación clinicopatológica y terapéutica / Thymomas: clinicopathological and therapeutical correlation

En un estudio sobre los timomas, en el que se clasificaron éstos de acuerdo con el tipo histológico y la etapa clínica, se confirmó que el tratamiento de elección de estos casos es la cirugía, preferiblemente mediante una esternotomía media longitudinal y aplicación de radioterapia y poliquimioterapia en los timomas invasivos