Visible-light photoelectrodegradation of diuron on WO3 nanostructures.

The degradation of pesticide diuron has been explored by photoelectrocatalysis (PEC) under visible light illumination using two different WO3 nanostructures, obtained by anodization of tungsten. The highest degradation efficiency (73%) was obtained for WO3 nanosheets synthesized in the presence of small amounts of hydrogen peroxide (0.05 M). For that nanostructure, the kinetic coefficient for diuron degradation was 133% higher than that for the other nanostructure (anodized in the presence of fluoride anions). These results have been explained by taking into account the different architecture and dimensions of the two WO3 nanostructures under study.

[Quadrature coils for magnetic resonance spectroscopy in the detection of prostate cancer: single voxel acquisition does not improve the diagnostic accuracy of multivoxel images]. / Complementariedad de la espectroscopía univóxel y la imágen de espectroscopía multivóxel obtenidas mediante bobina de cuadratura para la detección del carcinoma de próstata.

OBJECTIVE: To determine the viability of quadrature coils for detecting prostate cancer using single voxel and multivoxel spectroscopy images. MATERIAL AND METHODS: We used a quadrature coil on a 1.5T MR scanner to evaluate 23 patients with suspected prostate cancer and prostate specific antigen levels greater than 4ng/ml (mean 12±8ng/ml), independently of findings at digital rectal examination. We acquired T2-weighted images and MR spectroscopy images. We also acquired single voxel studies in areas in which the T2-weighted images or the multivoxel images were altered. We used a citrate solution to verify the spectroscopic calibration. RESULTS: Using spectroscopy images and a (Co+Cr)/Cit cutoff of 1.40 in single voxel spectroscopy, we achieved a sensitivity of 92%, specificity of 55%, a negative predictive value of 86%, and a positive predictive value of 69%. Using a cutoff of 0.75 decreased specificity slightly (45%). The (Co+Cr)/Cit ratio calculated for the single volume obtained from the most abnormal area in the T2-weighted images and in the multivoxel spectroscopy slices was not significantly different between cancerous and non-cancerous tissues (ANOVA, p=0.1), although there was a clear trend toward increased coefficients with hyperplasia and neoplastic degeneration. CONCLUSION: The quadrature coil enables multivoxel and single voxel spectroscopic images of clinically and technically acceptable quality to be obtained. Using single voxel spectroscopy does not improve the diagnostic performance of multivoxel spectroscopy and T2-weighted images.

Photoelectrocatalyzed degradation of a pesticides mixture solution (chlorfenvinphos and bromacil) by WO3 nanosheets.

A photoelectrocatalyst consisting of WO3 nanosheets or nanorods has been synthesized by electrochemical anodization under hydrodynamic conditions, and has been used for the degradation of two toxic pesticides: chlorfenvinphos and bromacil. Nanostructures have been characterized by FESEM and Raman spectroscopy. Photoelectrochemical degradation tests have been carried out both for individual pesticide solutions and for a mixture solution, and the concentration evolution with time has been followed by UV-Vis spectrophotometry. For individual pesticides, pseudo-first order kinetic coefficients of 0.402h-1 and 0.324h-1 have been obtained for chlorfenvinphos and bromacil, respectively, while for the mixture solution, these kinetic coefficients have been 0.162h-1 and 0.408h-1. The change in behavior towards pesticide degradation depending on whether individual or mixture solutions were used might be indicative of a competitive process between the two pesticide molecules when interacting with the WO3 nanostructures surface or when approaching the semiconductor/electrolyte interface.

[Total brain T2-hyperintense lesion-volume and the axonal damage in the normal-appearing white matter of brainstem in early lapsing-remitting multiple sclerosis]. / Relación entre el volumen lesional cerebral total en resonancia magnética secuencia T2 y el daño neuroaxonal en la sustancia blanca aparentemente normal del tronco del encéfalo en la esclerosis múltiple remitente-recurrente.

AIM: To evaluate the relationship between the total brain T2-hyperintense lesion volume (TBT2LV) and the axonal damage in the normal-appearing white matter of brainstem measured by 1H-MRS in a group of early relapsing-remitting multiple sclerosis patients. SUBJECTS AND METHODS: 40 relapsing-remitting multiple sclerosis patients and ten sex- and age-matched healthy subjects were prospectively studied for two years. T2-weighted MR and 1H-MRS imaging were acquired at time of recruitment and at year two. The TBT2LV was calculated with a semiautomatic program; N-acetylaspartate (NAA), creatine (Cr) and choline (Cho) resonances areas were integrated with jMRUI program and the ratios were calculated for four volume elements that represented the brainstem. RESULTS: At basal study we obtained an axonal loss (as a decrement of NAA/ Cho ratio) in the group of patients compared with controls (p = 0.017); this axonal loss increased at the second year of the follow-up for patients (NAA/Cho decrease, p = 0.004, and NAA/Cr decrease, p = 0.002) meanwhile control subjects had no significant metabolic changes. Higher lesion load was correlated with a poor clinical outcome, being the correlation between the basal TBT2LV and the Expanded Disability Status Scale at second year (r = 0.299; p = 0.05). Besides, axonal loss was not homogeneous for all multiple sclerosis patients, being stronger in the subgroup of patients with high basal TBT2LV (p = 0.043; ANOVA). CONCLUSION: Our data suggest that axonal damage is early in multiple sclerosis and higher in patients high basal TBT2LV, suggesting a possible relationship between these two phenomena.

MRS as endogenous molecular imaging for brain and prostate tumors: FP6 project "eTUMOR".

Molecular imaging has become during the last years in an important tool for supporting cancer diagnosis and prognosis. PET and SPECT are the most common molecular imaging techniques, although very promising and specific biological molecular agent contrast for CT and MRI are being recently developed. However, the above imaging techniques require exogenous contrast agents and usually a sole molecular image can be obtained at once. On the contrary, in vivo magnetic resonance spectroscopy (MRS), in particular 1H MRS can simultaneously provide several molecular images using endogenous metabolites. In addition to biochemical spatial information from molecular imaging spectroscopy, MRS can also provide average metabolite profile of the selected affected tissue region. Initially MRS, especially 1H MRS, was extensively applied to complete and improve the diagnosis and prognosis of central nervous system (CNS) pathologies, in particular brain tumors. However, during the last years the MRS applications have been extent to the diagnosis of different very common cancer types such as breast, prostate, colon carcinoma, and ovarian, among others. Likewise, MRS has been also used for lymph node assessment. In this contribution, the added value of MRS for the diagnosis, prognosis, and treatment selection of two different, important types of cancer: (1) brain tumors and (2) prostate, will be presented and discussed. Brain tumors are the leading cause of death in children under 15, and although in adults, brain cancers are proportionately less common than other cancers, it is a devastating disease with high mortality. There is a great need to increase our understanding of brain tumor biology to improve diagnosis and to develop new treatments. 1H MRS is currently the only noninvasive method that can be used to investigate molecular profile of brain tumors and also provide molecular images, more than six in one acquisition, of the distribution of chemicals in a tumor, which are also generally heterogeneous. A summary of the applications of 1H MRS to the in vivo diagnosis and prognosis of brain tumors will be presented. In addition, examples of metabolite limits, infiltration and high cellularity location for neurosurgery applications by MRS molecular images will be shown. Likewise, new ex vivo methods of studying the detailed biochemistry of tumor biopsies as metabolomic (high resolution magic angle spinning [HR-MAS]) and transcriptomic (DNA microarrays) will be discussed as complementary to in vivo MRS (FP6 European project eTUMOR). A preliminary comparison between molecular images from PET and 1H MRS will be also presented. Finally, the application of 1H MRS to the improvement of prostate diagnosis and prognosis, the second leading cause of cancer death, will also discussed, with particular attention to the location cancer contribution from MRS molecular images.

Parotid gland tissue is able partially to assume pituitary functions under the influence of hypothalamic factors: in vivo and in vitro studies.

To test whether salivary tissue can secrete pituitary hormones, female Sprague-Dawley rats were hypophysectomized (hypox) and the following were transplanted to the sella turcica: parotid gland (group 3, n=33), adrenal gland (group 4, n=30), muscle (group 5, n=24). Group 2 (n=21) had the sella turcica filled with dentist's cement. In addition a group of rats (group 1, n=22) remained intact as controls. All groups were followed for 8 months. Daily vaginal smears showed normal cyclicity in controls and constant dioestrus in all hypox groups. Blood samples, taken once every 30 days before and after LHRH stimulation, showed significantly lower (P<0.001) plasma LH values in all hypox groups compared with controls. In group 3, a gradual and significant increase (P<0.05) was observed in the LH response to LHRH in parallel with a partial recovery of oestrous smears. No LH modification was observed in the other hypox groups. Plasma prolactin (PRL) levels were also very low in all hypox groups and were unaltered throughout the study. At the end of the experiments, half the animals were killed by decapitation and the hypothalamic-pituitary areas carefully dissected, homogenized and analysed for LH and PRL content. The remaining animals were perfused with 4% paraformaldehyde to obtain fixing of the whole body tissues. Hypothalamic and transplant areas were carefully dissected, frozen, cut and submitted to immunochemical procedures. LH content in the graft of group 3 animals was markedly (P<0.001) lower than in the control pituitary, but significantly higher (P<0.05) than in the other hypox groups. Immunochemistry showed LH and PRL positive cells in the graft of group 3 animals, whereas neither positive cells, nor LH content were observed in the parotid gland in situ. Experiments were completed with in vitro cultures of parotid glands in the presence or absence (controls) of synthetic hypothalamic hormones or rat hypothalamic extracts. After 1.5 weeks of culture, a significantly higher LH concentration (P<0.05) was observed in the wells treated with synthetic hypothalamic hormones (216+/-46 pg/ml vs 41+/-6 pg/ml in controls). When hypothalamic extracts were used, the LH levels increased more markedly (1834+/-190 pg/ml vs 36+/-6 pg/ml in controls) and those values were maintained during 3 weeks of culture. Immunostaining of these cultures showed a positive LH reaction in the epithelial cells found in the hypothalamic extract-treated wells. Both in vivo and in vitro studies confirm the transdifferentiation of parotid gland tissue to pituitary hormone-producing cells under hypothalamic influence.

Salivary gland is capable of GH synthesis under GHRH stimulation.

Twelve female rats weighing approximately 150 g received in the submaxillary gland a pellet capable of releasing 3.5 microg GHRH/h for 60 days. Another eight sex- and weight-matched animals received placebo pellets in the same place. After two months the animals were killed, heart blood was collected and pituitary and submaxillary glands were carefully dissected. Pituitary GH content in both placebo- and GHRH-treated animals showed similar values, but plasma GH and IGF-I levels were significantly lower in the animals carrying GHRH pellets (P<0.03); these animals also had a significantly higher GH content in the submaxillary gland (19.2+/-8 ng/mg protein) compared with the placebo-treated group (1.1+/-0.3 ng/mg protein). GH mRNA was present only in the submaxillary gland of GHRH-treated rats as determined by PCR-Southern blot and by in situ hybridization methods. It is concluded that high local GHRH levels are capable of inducing transdifferentiation in submaxillary gland cells to synthesize GH.

Growth hormone response to long-term GH-RH administration in lambs.

The pattern of long-term GHRH administration capable of stimulating GH release without depleting pituitary GH content has been investigated using two experimental approaches. In experiment 1, recently weaned male lambs were treated for 3 weeks as follows: Group A) control; B) subcutaneous (sc) continuous infusion of GHRH (1200 mg/day) using a slow release pellet; C) the same as B plus 1 daily sc injection of long acting somatostatin (SS) (octreotide, 20 mg) ; D) 3 daily sc GHRH (250 mg) injections ; E) 2 daily sc injections of GHRH (250 mg) and 2 of natural SS (250 mg). In experiment 2, recently weaned male lambs were continuously GHRH-treated using sc osmotic minipumps (900 mg/day) alone or combined with a daily sc injection of octreotide (20 mg) for 4 weeks. Basal plasma GH levels were increased after chronic pulsatile GHRH treatment but not after any kind of continuous GHRH administration. This increment was maintained during the 3 weeks of experimentation and appeared accompanied by a pituitary GH content similar to controls. A marked GH response to the iv GHRH challenge was observed in controls and in lambs receiving both types of continuous sc GHRH infusions, whereas pulsatile sc GHRH-treated animals did not respond to the iv GHRH challenge in the first and second weeks of the study but did so in the third week of treatment. These data demonstrate that long-term pulsatile GHRH administration is capable of stimulating GH release in growing male lambs, without producing pituitary desensitization.

Adherence of mouse peritoneal macrophages following exposure to lead.

Lead is a toxin widely used in industry. Recently, medical investigation into lead exposure has turned to testing organ systems, such as the immune system, that historically were not associated with lead poisoning. We evaluated the effects of doses of 13, 130 or 1,300 ppm of lead on the adherence of mouse peritoneal cells, and particularly on macrophages. Cellular adherence was measured according to the De la Fuente technique. Adherence of macrophages showed significant changes in the 1,300 ppm group, revealing a reduction to 55% of the control group. The macrophage adherence index showed 91% sensitivity and 96% specificity. These results indicate a considerable reduction in the adherence of peritoneal macrophages following exposure to certain levels of lead.

Circadian rhythms in airline pilots submitted to long-haul transmeridian flights.

BACKGROUND: Circadian rhythms shift out of phase after transmeridian flights. Desynchronization between body rhythms and the environment is linked to jet lag, which depends on age, flight direction, and number of time zones crossed. METHODS: To investigate this problem in airline pilots, we performed a multivariate analysis of their circadian systems during Madrid-Mexico-Madrid flights (-7 time zones, n = 12) and Madrid-Tokyo-Madrid flights (+8 time zones, n = 21). Telemetry was used to record pilots' activity, skin temperature, and heart rate, obtaining 6 d of continuous data, including 2 d before the flight, the flights themselves, 2 d at the stopover, and 1 d after the return flight. Time series were analyzed by cosinor, and the resulting parameters of the rhythms were compared by ANOVA and Tukey contrasts in every category formed by the age groups (under and over 50 yr old) and flight direction groups. Subjective time estimation of short, intermediate, and long intervals was recorded. Other psychological variables were measured, including anxiety, tiredness, and performance. RESULTS AND CONCLUSIONS: Activity/rest and heart rate rhythms appeared to be linked to a "weak oscillator." Temperature rhythms manifested a rigid response after the phase shifts of the light/dark cycle, closely related to the biological clock. Subjective time appreciation tended to be overestimated without exhibiting a clear circadian component, but attributable to fatigue and stress. Psychometric evaluation showed that desynchronization affected all the pilots. Some results showed an age-related variability with a more marked influence in younger pilots. No consistent effects regarding flight direction were found.

Study of the inferior colliculus in patients with schizophrenia by magnetic resonance spectroscopy.

INTRODUCTION. Previous studies have suggested morphometric and functional abnormalities in the inferior colliculus in patients with schizophrenia. Auditory hallucinations are one of the central symptoms in schizophrenia. In this complex and multidimensional event both attention and emotion are thought to play a key role. AIM. To study metabolic changes in the inferior colliculus, a nucleus integrated in the auditory pathway, in patients with schizophrenia and the possible relationship with auditory hallucinations. SUBJECTS AND METHODS. Magnetic resonance spectroscopic imaging studies were performed in 30 right-handed patients with chronic schizophrenia (19 of them with auditory hallucinations) and 28 controls. A magnetic resonance spectroscopic imaging 2D slice was acquired and the voxels representative of both inferior colliculi were selected. N-acetylaspartate (NAA), creatine (Cr) and choline (Cho) peak areas were measured. RESULTS. The patients with schizophrenia showed a NAA/Cr significant reduction in the right inferior colliculus compared to the control subjects. The metabolic data in the right inferior colliculus were correlated with emotional auditory hallucinations items. CONCLUSIONS. The contribution of the inferior colliculus on neural underpinnings of auditory hallucinations is particularly relevant for the right inferior colliculus and is centered on attention-emotional component of this symptom.

TITLE: Estudio del coliculo inferior de pacientes con esquizofrenia mediante espectroscopia de resonancia magnetica.Introduccion. Algunos estudios anteriores en pacientes con esquizofrenia han sugerido alteraciones morfometricas y funcionales en el coliculo inferior. Las alucinaciones auditivas son uno de los sintomas centrales en la esquizofrenia. Se piensa que en este evento complejo y multidisciplinar, tanto la atencion como la emocion desempeñan un papel clave. Objetivo. Estudiar los cambios metabolicos en el coliculo inferior, un nucleo integrado en la via auditiva, en pacientes con esquizofrenia y su posible relacion con las alucinaciones auditivas. Sujetos y metodos. Se llevaron a cabo estudios de espectroscopia de resonancia magnetica en 30 pacientes diestros con esquizofrenia cronica (19 de ellos con alucinaciones auditivas) y 28 controles. Se adquirio una secuencia 2D de espectroscopia de resonancia magnetica y se seleccionaron los voxeles representativos de ambos coliculos inferiores. Se calculo el area de los picos de N-acetilaspartato (NAA), creatina (Cr) y colina (Co). Resultados. Los pacientes con esquizofrenia mostraron una reduccion significativa de NAA/Cr en el coliculo inferior derecho comparados con los sujetos control. Los datos metabolicos en el coliculo inferior derecho se correlacionaron con los items emocionales de las alucinaciones auditivas. Conclusiones. La contribucion del coliculo inferior a las bases neuronales de las alucinaciones auditivas es particularmente relevante para el coliculo inferior derecho y se centra en el componente atencional-emocional de este sintoma.

Spectroscopic metabolomic abnormalities in the thalamus related to auditory hallucinations in patients with schizophrenia.

OBJECTIVE: Previous studies have found neurochemical abnormalities in thalamic nuclei in patients with schizophrenia. These abnormalities have been associated with information processing deficiencies and symptom formation. There are no metabolic spectroscopy studies in patients with schizophrenia attending to auditory hallucinations. The aim of the present study is to explore metabolic Magnetic Resonance Spectroscopy (MRS) ratio differences in the thalamus between schizophrenic patients with and without auditory hallucinations and control subjects. METHODS: MRS studies (MRI 1.5 T unit) were performed in 49 patients with schizophrenia (30 with auditory hallucinations and 19 without auditory hallucinations) and 37 controls. (1)H MRS imaging was used to acquire 2 transverse slices (TR/TE 2700/272 ms, region of interest 110 x 100 x 23 mm). In the quantitative analysis four elements of volume (9.2 x 9.2 x 23 x 4 mm), added into one spectrum representative of each thalamus, were chosen in the slice passing through the main body of the thalamus. The areas of metabolites were integrated with the jMRUI program. RESULTS: The patients with schizophrenia had significantly lower bilateral NAA/Cho ratios when compared with healthy subjects. There was also a lower NAA/Cho ratio in the right thalamus in patients with auditory hallucinations compared to patients without auditory hallucinations and control subjects. Significant correlations were found between metabolic ratios and BPRS, PANSS and PSYRATS scores, age of onset of auditory hallucinations, and age of subjects. CONCLUSIONS: Choline and NAA ratio abnormalities determined by thalamic spectroscopy may be related to the pathogenesis of auditory hallucinations in patients with schizophrenia.

[Dementias: diagnostic contribution of imaging and proton magnetic resonance spectroscopy]. / Demencias: contribución diagnóstica de la imagen y de la espectroscopia de resonancia magnética de protón.

INTRODUCTION: The objective is analyze the complementarity between 1H magnetic resonance spectroscopy (MRS) and magnetic resonance (MR) imaging in the global diagnosis of Alzheimer's disease (AD) or vascular dementia (VD). METHODS: We studied 168 patients with cognitive impairment from AD, VD, mild cognitive impairment (MCI) and major depression. All patients were evaluated by brain MR imaging and MRS using two sample volumes localized at right medial temporal gyrus and posterior parietal gyrus. Metabolites analyzed were N-acetylaspartate (NAA), myo-Inositol (mI), Choline (Cho) and creatine (Cr), as standard references for obtaining the Co/Cr, mI/Cr and NAA/Cr ratios. Imaging and spectroscopy alterations were graded from 0 to 4 and the average of both was used to draw ROC and SROC curves. Area under ROC curve (Az) was used as a measure of discriminative ability. RESULTS: Combination of MR imaging and MRS significantly improved AD diagnosis (Global Az: 0.722 vs. MR imaging Az: 0.624; p: 0.003). However, the combination of MR imaging and MRS did not improve VD diagnosis. SROC curve obtained for the diagnosis of global dementia was Az: 0.6658 with 0.67 sensitivity and 0.65 specificity. CONCLUSIONS: Combination of both MR techniques significantly improved AD diagnosis versus MR imaging alone. More studies are needed to enhance VD classification. Metabolic data found by MRS can be useful to differentiate cognitive impairment

Axonal loss is progressive and partly dissociated from lesion load in early multiple sclerosis.

OBJECTIVE: To assess the relationship between the spectroscopically measured axonal damage in the normal-appearing white matter of the brainstem, the total brain T2-hyperintense lesion volume (T2LV), and disability in patients with early relapsing-remitting multiple sclerosis (RRMS). METHODS: Forty-three RRMS patients and 10 sex- and age-matched healthy controls were prospectively studied for 2 years. T2-weighted magnetic resonance (MR) images and proton MR spectroscopy were acquired at the time of recruitment and at year 2. Brainstem was considered, where large tracts join together, as a suitable region to detect early axonal damage. The T2LV was calculated with a semiautomatic program; N-acetylaspartate (NAA), creatine (Cr), and choline (Cho) resonances areas were integrated with the jMRUI program, and the ratios were calculated for the sum of the volume elements represented at brainstem. RESULTS: The basal NAA/Cho ratio was significantly decreased in patients compared with controls. After 2-year follow-up, there was a decrease in the NAA/Cho (-9%; p = 0.002) and NAA/Cr (-13%; p = 0.001) ratios, and an increase in the T2LV (19%; p = 0.043) in multiple sclerosis patients, whereas control subjects had no significant metabolic changes. Significant NAA/Cr ratio decreases were observed in both patients, with and without relapses, whereas T2LV only increased in patients with relapses. The final Expanded Disability Status Scale (EDSS) score correlated with T2LV at baseline, but no significant correlations were found between metabolic values, T2LV change, or EDSS score over the study period. CONCLUSIONS: Our data reveal an early and progressive axonal damage in relapsing-remitting multiple sclerosis. Axonal loss and T2 lesion volume seem to be at least partly dissociated processes in early stages of the disease.

[Cognitive impairment: classification by proton magnetic resonance spectroscopy and the contributions of conventional magnetic resonance imaging]. / Deterioro cognitivo: clasificación mediante espectroscopia de resonancia magnética de protón y contribución de la imagen convencional.

OBJECTIVE: To analyze the diagnostic accuracy of proton magnetic resonance spectroscopy (1H MRS) in patients with cognitive impairment and to establish the usefulness of complementary information provided by conventional magnetic resonance imaging (MRI). MATERIAL AND METHODS: 64 patients with cognitive impairment, including Alzheimer's disease (AD) (n=31), vascular dementia (n=6), mild cognitive impairment (MCI) (n=9), and major depression (n=18), were studied. All patients underwent cerebral MRI and single-volume 1H MRS using two echo times (TE, 31 and 136 ms) in the posterior cingulate gyrus and right temporal lobe. The metabolites analyzed were N-acetylaspartate (NAA), myo-Inositol (mI), choline (Ch), and creatine (Cr), and the ratios of Ch/Cr, mI/Cr, NAA/mI and NAA/Cr were calculated. In order to differentiate among the different types of cognitive impairment, the alterations in imaging and spectroscopy findings were graded from 0 to 4, as was the mean combination of the two, and then ROC curves were obtained. RESULTS: Statistically significant differences were found between the spectra of patients with dementia (AD and vascular dementia) and those without dementia (MCI and depression) in the posterior cingulate gyrus. The NAA/mI ratio yielded the best area under the ROC curve, with the best sensitivity (82.5%) and specificity (72.7%) in the diagnosis of AD. The NAA/mI and mI/Cr quotients differentiated between the four degenerative pathologies causing the cognitive impairment. The combination of MRI and 1H MRS significantly improved the accuracy of the diagnosis of AD. CONCLUSIONS: The metabolic differences found among patients with cognitive impairment using 1H MRS can be useful for differentiating AD, vascular dementia, MCI, and depression. The combination of spectroscopy and MRI findings is useful in the diagnosis of AD.

Circadian urinary 6-sulphatoxymelatonin, cortisol excretion and locomotor activity in airline pilots during transmeridian flights.

Airline pilots divided into two groups of age (over and under 50 years) were studied before, during and after westbound (Madrid-Mexico City-Madrid, n = 12) and eastbound (Madrid-Tokyo-Madrid, n = 21) flights. A group of 10 age-matched people staying in Madrid were submitted to the same tests and served as a control group. Changes in urinary 6-sulphatoxymelatonin (6-aMTs) and free cortisol excretion (determined in 6-hr intervals) were measured by radioimmunoassay. Using wrist actigraphy, the circadian locomotor activity rhythm (LAR) was also monitored. Maximal baseline excretion of 6-aMTs occurred between 00:00 and 12:00 hr and maximal excretion of cortisol took place between 6:00 and 12:00 hr in the control group. Analysed globally, older pilots exhibited significantly lower values of 6-aMTs than younger ones. In both flight directions, pilots maintained the pattern of excretion of 6-aMTs, corresponding to baseline. The return flight to Madrid from Mexico and Tokyo coincided with a maximum in 6-aMTs excretion. Pilots kept the cortisol pattern found in the control group, with those over 50 years of age exhibiting significantly lower cortisol values than the younger ones. A 7-hr delay in acrophase of LAR after 2 days in Mexico City was found after cosinor analysis, and similar pre-flight values were found after returning to Madrid. An 8-9-hr acrophase advance of LAR was observed after arriving in Tokyo, with acrophase on the post-return flight day still being advanced 3 4 hr as compared to pre-flight values. Decreases in the amplitude of LAR in older pilots were found at Mexico City, as well as at Tokyo stopover and on post-flight day. Data confirm the occurrence of internal desynchronization in airline crewmembers after transmeridian flights.

Effects of bromocriptine administration during the follicular phase of the oestrous cycle on prolactin and gonadotrophin secretion and follicular dynamics in merino monovular ewes.

Two experiments using Spanish Merino ewes were conducted to investigate whether the secretion of prolactin during the follicular phase of the sheep oestrous cycle was involved in the patterns of growth and regression of follicle populations. In both experiments, oestrus was synchronized with two cloprostenol injections which were administered 10 days apart. Concurrent with the second injection (time 0), ewes (n = 6 per group) received one of the following treatments every 12 h from time 0 to 72 h: group 1: vehicle injection (control); group 2: 0.6 mg bromocriptine (0.03 mg per kg per day); and group 3: 1.2 mg bromocriptine (0.06 mg per kg per day). In Expt 1, blood samples were collected every 3 h from 0 to 72 h, and also every 20 min from 38 to 54 h to measure prolactin, LH and FSH concentrations. In Expt 2, transrectal ultrasonography was carried out every 12 h from time 0 until oestrus, and blood samples were collected every 4 h to measure prolactin, LH and FSH concentrations. Ovulation rates were determined by laparoscopy on day 4 after oestrus. Bromocriptine markedly decreased prolactin secretion, but did not affect FSH concentrations, the mean time of the LH preovulatory surge or LH concentrations in the preovulatory surge. Both doses of bromocriptine caused a similar decrease in LH pulse frequency before the preovulatory surge. The highest bromocriptine dose led to a reduction (P < 0.01) in the number of 2-3 mm follicles detected in the ovaries at each time point. However, bromocriptine did not modify the total number or the number of newly detected 4-5 mm follicles at each time point, the number of follicles > 5 mm or the ovulation rate. In conclusion, the effects of bromocriptine on gonadotrophin and prolactin secretion and on the follicular dynamics during the follicular phase of the sheep oestrous cycle indicate that prolactin may influence the viability of gonadotrophin-responsive follicles shortly after luteolysis.

Complementariedad de la espectroscopía univóxel y la imágen de espectroscopía multivóxel obtenidas mediante bobina de cuadratura para la detección del carcinoma de próstata / Quadrature coils for magnetic resonance spectroscopy in the detection of prostate cancer: Single voxel acquisition does not improve the diagnostic accuracy of multivoxel images

Objetivo. Demostrar la viabilidad de la bobina de cuadratura para la detección del cáncer de próstata mediante espectroscopía univóxel e imágen multivóxel. Material y métodos. Se evaluaron 23 pacientes con sospecha de carcinoma de próstata, con niveles del antígeno especifico de próstata superior a 4ng/ml, (media 12±8ng/ml), independientemente del tacto rectal, estudiados en un equipo de RM de 1,5T con la bobina de cuadratura. Se adquirieron imágenes potenciadas en T2 e imágenes de espectroscopía. También se adquirieron estudios univóxel en aquellas zonas donde la imágen T2 o la imágen multivóxel estaban alteradas. Se realizó un control metodológico de espectroscopía con una disolución patrón de citrato. Resultados. Con la imágen espectroscópica y un punto de corte [(Co+Cr)/Cit] de 1,40 en el vóxel único se alcanzan unos valores de sensibilidad del 92%, especificidad del 55%, predictivo negativo del 86% y predictivo positivo del 69%. Con un punto de corte de 0,75, la especificidad disminuye discretamente (45%). La relación [(Co+Cr)/Cit] calculada para el volumen único obtenido del área más anormal en el T2 y en los cortes de espectroscopía multivóxel no mostró diferencias significativas entre tejidos no tumorales y carcinomas (ANOVA, p=0,1), aunque se observó una clara tendencia a aumentar el cociente con la hiperplasia y la degeneración neoplásica. Conclusión. La bobina de cuadratura permite obtener imágen multivóxel y espectros univóxel con una calidad técnica y clínicamente aceptables. El empleo de la espectroscopía univóxel no mejora la rentabilidad diagnóstica de la espectroscopía multivóxel y la imágen T2(AU)

Objective. To determine the viability of quadrature coils for detecting prostate cancer using single voxel and multivoxel spectroscopy images. Material and methods. We used a quadrature coil on a 1.5T MR scanner to evaluate 23 patients with suspected prostate cancer and prostate specific antigen levels greater than 4ng/ml (mean 12±8ng/ml), independently of findings at digital rectal examination. We acquired T2-weighted images and MR spectroscopy images. We also acquired single voxel studies in areas in which the T2-weighted images or the multivoxel images were altered. We used a citrate solution to verify the spectroscopic calibration. Results. Using spectroscopy images and a (Co+Cr)/Cit cutoff of 1.40 in single voxel spectroscopy, we achieved a sensitivity of 92%, specificity of 55%, a negative predictive value of 86%, and a positive predictive value of 69%. Using a cutoff of 0.75 decreased specificity slightly (45%). The (Co+Cr)/Cit ratio calculated for the single volume obtained from the most abnormal area in the T2-weighted images and in the multivoxel spectroscopy slices was not significantly different between cancerous and non-cancerous tissues (ANOVA, p=0.1), although there was a clear trend toward increased coefficients with hyperplasia and neoplastic degeneration. Conclusion. The quadrature coil enables multivoxel and single voxel spectroscopic images of clinically and technically acceptable quality to be obtained. Using single voxel spectroscopy does not improve the diagnostic performance of multivoxel spectroscopy and T2-weighted images(AU)

Test para la Evaluación de la Calidad de Vida en Adictos a Sustancias Psicoactivas (TECVASP): estudios de fiabilidad y validez / Assessment of the quality of life in psychoactive substance addicts test: reliability and validity studies

Objetivo. Estudiar la fiabilidad y aportar evidencias de validez del Test para la Evaluación de la Calidad de Vida en Adictos a Sustancias Psicoactivas (TECVASP). Método. En la investigación participaron 359 pacientes de cinco comunidades terapéuticas gestionadas por la Fundación Andaluza para la Atención a las Drogodependencias. Además del TECVASP, se aplicó la sección de «uso de sustancias» de la versión española del Maudsley Addiction Profile (MAP) y se recogió información sociodemográfica de los pacientes. Resultados. La estimación de fiabilidad, calculada con el coeficiente alfa de Cronbach, fue adecuada, con un valor de 0,861. En los tres estudios de validación se muestran evidencias a favor del uso de las puntuaciones del test para el objetivo previsto, ya que se detectan diferencias en la calidad de vida relacionada con la salud (CVRS) en pacientes: 1) incluidos en programa de desintoxicación con la de otros que están en deshabituación, 2) consumidores de «rebujo» (mezcla de heroína y cocaína base) que están en programa de tratamiento con metadona con la de otros que no están en tratamiento con metadona, y 3) al ingreso en comunidad terapéutica y al finalizar el tratamiento. Conclusiones. Las propiedades métricas obtenidas señalan la pertinencia del TECVASP para medir la CVRS de personas drogodependientes, recomendando su uso cuando se quiera estimar la CVRS de pacientes que se encuentran en distintas fases del tratamiento de la dependencia

Objective. In this work, different studies of the metric properties —estimate of reliability and evidences of validity— of Test for the Evaluation of the Quality of Life in Addicts to Psychoactive Substances (TEQLAPS) is carried out. Method. In the investigation 359 patients of five therapeutic communities participated egotiated by the Andalusian Foundation for Attention to Drugs Addictions. Besides the TEQLASP, the section of «use of substances» of the Spanish version of the Maudsley Addiction Profile (MAP) were delivered, and the patients’ sociodemographics information was picked up. Results. The estimate of reliability, calculated with Cronbach alpha coefficient, it was adequate, with a value of 0,861. In the three studies of validation evidences are shown in favour of test use for foreseen objective, since: 1) differences in the Health Related Quality of Live (HRQL) between patients in detoxification and dishabituation program are detected; 2) differences in the HRQL between heroin with base cocaine abusers that are in treatment program with methadone and not in treatment with methadone are detected; and, 3) differences in the HRQL from the patients to the entrance in the therapeutic communities and when concluding the treatment are detected. Conclusions. The obtained metric properties point out the relevancy of the TEQLASP to measure the HRQL of drug addict people, recommending their use when the HRQL of patients that are in different phases of the treatment of the dependence to differ

Demencias: contribución diagnóstica de la imagen y de la espectroscopia de resonancia magnética de protón / Dementias: diagnostic contribution of imaging and proton magnetic resonance spectroscopy

Introducción. El objetivo es establecer la complementariedad de imagen y espectroscopia de resonancia magnética de protón (1HERM) en el diagnóstico global de demencia Alzheimer (DA) o demencia vascular (DV). Métodos. Se estudiaron 168 pacientes con deterioro cognitivo comprendiendo DA, DV, deterioro cognitivo leve (DCL) y depresión mayor. Todos se exploraron con resonancia magnética (RM) cerebral y 1HERM, adquiriendo espectros del cíngulo posterior y circonvolución temporal media derecha. Los metabolitos analizados fueron N-acetilaspartato (NAA), mio-inositol (Mi) y colina (Co) con la creatina (Cr) como metabolito de referencia para las relaciones Co/Cr, Mi/Cr y NAA/Cr. Las alteraciones en imagen y espectroscopia fueron graduadas de 0 a 4, así como la combinación promedio de las mismas, obteniéndose curvas ROC y SROC, con el criterio de área bajo la curva como capacidad discriminativa (Az). Resultados. La combinación de imagen de RM y 1HERM mejoró significativamente el diagnóstico de DA (Az global: 0,722, frente a RM Az: 0,624; p= 0,003). Sin embargo, la combinación de RM y 1HERM no mejoró el diagnóstico de DV. La curva SROC para el diagnóstico global de demencia mostró una Az de 0,6658, con sensibilidad y especificidad de 0,67 y 0,65, respectivamente. Conclusiones. La combinación de las dos técnicas de RM (imagen y espectroscopia) mejoró el diagnóstico de DA frente a la imagen aislada, mejorando el diagnóstico de forma estadísticamente significativa. Se necesitan mayores estudios para la mejora de la clasificación de la DV. Las diferencias metabólicas encontradas mediante ERM entre pacientes pueden ser útiles para diferenciar el deterioro cognitivo

Introduction. The objetive is analyze the complementarity between 1H magnetic resonance spectroscopy (MRS) and magnetic resonance (MR) imaging in the global diagnosis of Alzheimer's disease (AD) or vascular dementia (VD). Methods. We studied 168 patients with cognitive impairment from AD, VD, mild cognitive impairment (MCI) and major depression. All patients were evaluated by brain MR imaging and MRS using two sample volumes localized at right medial temporal gyrus and posterior parietal gyrus. Metabolites analyzed were N-acetylaspartate (NAA), myo-Inositol (mI), Choline (Cho) and creatine (Cr), as standard references for obtaining the Co/Cr, mI/Cr and NAA/Cr ratios. Imaging and spectroscopy alterations were graded from 0 to 4 and the average of both was used to draw ROC and SROC curves. Area under ROC curve (Az) was used as a measure of discriminative ability. Results. Combination of MR imaging and MRS significantly improved AD diagnosis (Global Az: 0.722 vs. MR imaging Az: 0.624; p: 0.003). However, the combination of MR imaging and MRS did not improve VD diagnosis. SROC curve obtained for the diagnosis of global dementia was Az: 0.6658 with 0.67 sensitivity and 0.65 specificity. Conclusions. Combination of both MR techniques significantly improved AD diagnosis versus MR imaging alone. More studies are needed to enhance VD classification. Metabolic data found by MRS can be useful to differentiate cognitive impairment