TCNQ molecular semiconductor of the Cu(II)TAAB macrocycle: Optical and electrical properties.

The present study reports the doping of a semiconducting molecular material through the formation of hydrogen bonds between the macrocycle Cu(II)(TAAB) and the electronic acceptor TCNQ. According to density functional theory (DFT) calculations and electron paramagnetic resonance (EPR) analysis, the doped compound has the shape of a distorted square pyramid, with four nitrogen atoms in the equatorial position and the apical oxygen atom from the water ligands. These water molecules can generate strong hydrogen bonds with TCNQ and the TAAB metallic complex. Thin films of copper molecular material were obtained through high vacuum evaporation and were structurally characterized by IR spectroscopy, EPR and scanning electron microscopy (SEM). Additionally, the absorption coefficient (α) and photon energy (hν) were calculated from UV-vis spectroscopy and used to determine the optical activation energy in each film, from which its semiconducting behavior was established. An important aspect to consider is that the presence of hydrogen bonds is essential to establish the semiconducting nature of these species; this chemical behavior, as well as the resulting electronic mobility, have been studied by DFT theoretical calculations, which reinforce the experimental conclusion of a relationship between Cu(II)TAAB and TCNQ moieties generated by a weak bond. Finally, I-V characteristics have been obtained from a glass/ITO/doped molecular semiconductor/Ag device using Ag and ITO electrodes. Results for the copper-based device show that, at low voltages, the conduction process is of an ohmic nature while, at higher voltages, space-charge-limited current (SCLC) is found. It is highly probable that the doping effect in TCNQ favors electronic transport due to the formation of conduction channels caused by dopant-favored anisotropy.

Templated co-assembly into nanorods of polyanions and artificial virus capsid proteins.

Recombinant triblock polypeptides C-Sn-B, where C is a 400 amino acid long hydrophilic random coil block, Sn is a multimer of the silk-like octapeptide S = (GAGAGAGQ), and B = K12 is an oligolysine, have previously been shown to encapsulate double stranded DNA into rod-shaped, virus-like particles. In order to gain insight of the co-assembly process, and in order to be able to use these proteins for templating other types of nanorods, we here explore their co-assembly with a range of polyanionic templates: poly(acrylic acids) (PAA) of a wide range of lengths, poly(styrene sulphonate) (PSS) and the stiff anionic polysaccharide xanthan. The formation of the complexes was characterized using Dynamic Light Scattering (DLS), cryogenic Transmission Electronic Microscopy (Cryo-TEM) and Atomic Force Microscopy (AFM). Except at very high molar masses, we find that flexible anionic PAA and PSS lead to co-assembly of proteins with single polyanion chains into nanorods, with a packing factor as expected on the basis of charge stochiometry. Only for very long PAA templates (8 × 105 Da) we find evidence for heterogeneous complexes with thin and thick sections. For the very stiff xanthan chains, we find that its stiffness precludes co-assembly with the artificial viral capsid proteins into condensed and regular nanorods. Given the simple and robust formation of rod-like structures with a range of polyanionic templates, we anticipate that the artificial virus proteins will be useful for preparing high-aspect ratio nanoparticles and scaffolds of precise size and find applications in nanotechnology and materials science for which currently natural rod-like viruses are being explored.

Prognostic value of gasometric parameters of carbon dioxide in resuscitation of septic patients. A bibliography review.

The anaerobic metabolism is the cornerstone in physiopathology of septic shock. Nowadays we have both the central or mixed venous oxygen saturation and lactate levels to monitoring the metabolism in septic patients. Some studies have shown that normalization of systemic hemodynamic and oxygen metabolism variables not prevent progression to multiorgan damage and death. Recently has been proposed the venous-to-arterial carbon dioxide difference (ΔpvaCO2) as an alternative marker of tissue hypoperfusion, like Cardiac Index. High ΔpvaCO2 predicts adverse outcomes. Also has been proposed both, the ratio between the ΔpvaCO2 and arterial-to-venous oxygen content difference (ΔCavO2): ΔpvaCO2/ΔCavO2; and, the ratio between venous-to-arterial carbon dioxide difference (ΔCvaCO2) and ΔCavO2: ΔCvaCO2/ΔCavO2, as markers of anaerobic metabolism. Both of high ratios are related to high levels of lactate and worse prognosis. Therefore in patients with sepsis the combination of markers of resuscitation could be important to improve the outcomes.

In vitro evaluation of cell death induced by cadmium, lead and their binary mixtures on erythrocytes of Common buzzard (Buteo buteo).

Cadmium and lead are persistent and ubiquitous metals that can cause several deleterious effects in living beings. Apoptosis and necrosis are two types of cell death that can be found after in vivo and in vitro exposure to these metals. In this study, isolated red blood cells from living captive Common buzzard (Buteo buteo) were exposed in vitro to different concentrations of lead, cadmium, and the mixture lead-cadmium in a proportion of 1:10 (similar to that found in previous field studies). Data obtained from dose-response curves were used to evaluate the interactive effects of metal mixtures on cell viability. In general, except for the exposure to NOEC, additivity was the most frequently observed response. As described in human, after in vitro exposure, lead was highly accumulated in buzzard erythrocytes, while cadmium accumulation was scarce. Finally, the type of cell death (apoptosis or necrosis) induced by the exposure to different concentrations of these heavy metals and their mixtures was evaluated in the red blood cells. Apoptosis was found to be the main type of cell death observed after cadmium and/or lead exposure. However, this exposure caused an increase in lysis or necrosis, especially if red blood cells were exposed to high doses.

Phycobiliproteins or C-phycocyanin of Arthrospira (Spirulina) maxima protect against HgCl(2)-caused oxidative stress and renal damage.

Our objective was to determine if the phycobiliproteins of Arthrospira (Spirulina) maxima protect renal cells against mercury-caused oxidative stress and cellular damage in the kidney. We used 40 male mice that were assigned into eight groups: (1) a control group that received 100mM phosphate buffer (PB) ig and 0.9% saline ip, (2) PB+HgCl(2) (5mg/kg ip), (3) PB plus phycobiliproteins (100mg/kg ig), (4) PB plus C-phycocyanin (100mg/kg ig), and four groups receiving HgCl(2)+phycobiliproteins or C-phycocyanin (50, and 100mg/kg ig). The left kidneys were used to determine lipid peroxidation, quantification of reactive oxygen species, and reduced glutathione and oxidised content. The right kidneys were processed for histology. The HgCl(2) caused oxidative stress and cellular damage. All doses of phycobiliproteins or C-phycocyanin prevented enhancement of oxidative markers and they protected against HgCl(2)-caused cellular damage.

Palmitone prevents pentylenetetrazole-caused neuronal damage in the CA3 hippocampal region of prepubertal rats.

Palmitone is a secondary metabolite of polyketide origin extracted from leaves of Annona diversifolia Saff. (Annonaceae). We found that palmitone possesses anticonvulsant properties against penicillin-, 4-AP-, and pentylenetetrazole (PTZ)-caused seizure in adult animals. Some convulsants as PTZ cause neuronal damage in different brain regions such as the CA3 hippocampal region. Our objective was to evaluate if palmitone protects against PTZ-caused seizures and hippocampal neuronal damage in prepubertal rats. We used 32 prepubertal Wistar rats (30-35 days old) divided into four groups of 8 animals; group I was the control group, group II received a single PTZ dose of 50mg/kg ip, group III received a single palmitone dose of 50mg/kg ip, and group IV received a palmitone dose of 50mg/kg ip plus a PTZ dose of 50mg/kg ip. Ten days after administration, the animals were killed using pentobarbital anesthesia (35 mg/kg). The brains were removed and were embedded in paraffin. Coronal cuts of 7 microm were obtained from -2.8 to -3.3 from Bregma. Each section was stained with cresyl violet-eosin. We evaluated the number of normal and abnormal neurons in the CA3 hippocampal region in a 10,000 microm(2) section. It was observed that palmitone did not prevent the PTZ-caused seizure but palmitone prevents the PTZ-caused neuronal damage in the CA3 hippocampal region.

Cadmium- and lead-induced apoptosis in mallard erythrocytes (Anas platyrhynchos).

Cadmium, lead and cadmium-lead (1:10) induced apoptosis were studied using mallard blood cells. The allowable range in concentrations were: 0.01-0.5, 0.1-5.0, and 0.01:0.10-0.50:5.00 mM, for cadmium, lead and cadmium-lead, respectively. The lowest EC(50) achieved was for cadmium (0.22+/-0.04 mM). Two doses from each treatment group were chosen to study apoptosis and the presence of metals in cells. The percentage of apoptotic cells increased as the concentration of metals increased. The percentage of cells with intracellular metals was high for both exposure levels and the quantity of intracellular metal was greater for exposure to high concentrations. Morphological alterations for all types of exposure were related to the diverse range of effects that these metals have on membranes. We suggest that the decrease in the number of erythrocytes observed in specimens suffering from lead and cadmium poisoning is related to the induction of apoptosis.

Valoración de las alteraciones provocadas por diferentes agentes tóxicos sobre Daphnia magna a través de un ensayo “on line" / Real-time monitoring of alterations in daphnia magna induced by differents toxic agents

El presente estudio se realizó con el objetivo de determinar la capacidad de detección de compuestos tóxicos presentes en agua a través de un ensayo on line con el equipo “Daphnia-Toximeter". Se analizó la respuesta de las daphnias tras la exposición durante 7 horas a plomo, cadmio, mercurio, cobre, cianuro, cipermetrina, diazinon, clorpirifos, y a una combinación de i nse ctic idas (c lorpirifos + di clorvos + propoxur). L as concentraciones de xenobióticos ensayadas fueron las máximas permitidas por la legislación europea para aguas destinadas a consumo humano. Los parámetros a evaluar en la población de daphnias fueron los siguientes: velocidad media, clases de velocidad, índice de clases de velocidad, altitud media, dimensión fractal, número de individuos en movimiento, tamaño medio, distancia media, relación de reconocimiento, e índice de toxicidad como s umatorio de todos los parámetros anteriormente citados. Simultáneamente se analizó la respuesta tras la exposición estática a los mismos compuestos. En el caso del plomo, cadmio y mercurio no observamos alteraciones en la población de daphnias. Con el cobre se produjeron alteraciones en todos los parámetros. Con el resto de compuestos se produjeron alteraciones cuantificadas a través del índice de toxicidad. Los resultados de la exposición estática se cuantificaron en términos de muerte de las daphnias, ocurriendo ésta tras la exposición a cobre, cianuro y plaguicidas. El estudio demuestra la capacidad de respuesta on line de las daphnias ante la acción de diferentes compuestos disueltos en agua y en suspensión, aunque es completamente imprescindible la realización de nuevos experimentos para estandarizar las condiciones de ensayo y la valoración de respuesta ante otros compuestos (AU)

The present study was carried out with the aim of determining the capacity of a "Daphnia-Toximeter" equipment to detect toxic compounds in water in a real-time assay. The response of the daphnia was tested after a seven-hour exposure to lead, cadmium, mercury, copper, cyanide, cypermetrin, diazinon, chlorpyrifos and a combination of insecticides (chlorpyrifos + dichlorvos + propoxur). The xenobiotic concentrations assayed were the maximum permitted by current legislation for water destined for human consumption. The following parameters were evaluated in the daphnia population: average speed, division of speed, speed class-index, number of daphnia capable of moving, average altitude, medium size, fractal dimension, middle distance, recognition rate and toxicity index, representing the sum of all the previous parameters. At the same time, the response after static exposure to the same compounds was analysed using the conventional method with Daphnia magna. In the case of lead, cadmium and mercury, no alterations in the daphnia population were observed in the real-time assay, while copper produced alterations in all parameters. The other compounds produced substantial quantitative alterations in the toxicity index. The results of static exposure were quantified in terms of daphnia death after exposure to copper, cyanide and the pesticides. The study demonstrates the real-time response capacity of daphnia to the action of different toxic compounds dissolved and in suspension in the water, although new experiments are essential for standardising the assay conditions and for evaluating the response of other compounds (AU)

Aspectos clínicos y forenses del envenenamiento de aves silvestres: diferencias entre aldicarb y estricnina / Clinical and forensic aspects of the poisoning of wild birds: differences between aldicarb and strychnine

Aldicarb y estricnina son frecuentemente usados para envenenar fauna silvestre y doméstica. La estricnina se utilizó ampliamente hace algunos años hasta que fue prohibido su uso en 1994, siendo sustituida por otros plaguicidas carbamatos como el aldicarb o el carbofurano. En los últimos años se ha producido un aumento de envenenamientos por estricnina. Los síntomas de la intoxicación por estricnina y carbamatos están ampliamente descritos en mamíferos, pero no en aves. En la mayoría de los casos forenses la única información disponible es el análisis químico-toxicológico del cadáver o del cebo. Esta carencia de información es debida, en gran medida, a un inadecuado manejo y procesado de la escena del crimen, la inadecuada formación de los agentes para tomar y embalar las muestras, y/o la falta de formación toxicológica y/o forense de los veterinarios. La escena del crimen es solo uno de los componentes de la investigación pero necesita ser coordinada con los otros aspectos de la investigación. La escena del crimen debe ser estudiada hasta el más mínimo detalle para establecer un correcto diagnóstico. En este trabajo, utilizando como referencia el envenenamiento por aldicarb y estricnina, enfatizamos algunos aspectos clínicos y forenses que deben ser tenidos en cuenta en la investigación del envenenamiento de aves silvestres

Aldicarb and strychnine are frequently used to poison wild and domestic animals. Strychnine was widely used until it was banned in 1994, being substituted for carbamates such as aldicarb or carbofuran. Recently, an increase of deliberated poisonings using strychnine has been observed. Symptoms of aldicarb and strychnine poisonings have been widely described in mammals, however they have been poorly reported in birds. In most forensic cases the only available data is the chemical analysis realized on baits or tissues from dead animals. This scarcity of information is due usually to an inadequate management and processing of the crime scene, an unsuitable training of the first officer to collect and package the physical evidences, and/or unsuitable toxicological and forensic training of the veterinarians. Is should be recognized the crime scene is only one component of an investigation and needs to be coordinated with other aspects of the investigation. The crime scene should be investigated down to the last detail in order to establish an accurate diagnosis. In this work, using aldicarb and strychnine poisonings as references, we emphasize some clinical and forensic aspects which should be taken into account in the investigation of poisoning of wild birds

[Intestinal parasitosis in the asymptomatic Subsaharian immigrant population. Gran Canaria 2000]. / Parasitosis intestinales en población inmigrante subsahariana asintomática. Gran Canaria 2000.

CONTEXT: A prospective study has been conducted in order to known the prevalence and the type of intestinal parasitoses in a cohort of healthy Subsaharian immigrants that reached Gran Canaria along the year 2000. METHODS: 348 fecal samples of 121 immigrants have been studied. In each patient a minimum of two samples and a maximum of three samples was studied. Each sample was evaluated through two techniques: visualization of a direct preparation dyed with Lugol and through the technique of concentration of Kato. RESULTS: 23.1% of the patients presented pathogenic parasites in feces, being observed 2 parasites in 5 of the patients (17.8%). The geohelminths (Ancylostoma duodenale/Necator americanus, Ascaris lumbricoides, Trichuris trichiura and Strongyloides stercolaris) were the parasites more frequently found (87.9%). Specifically, the parasitosis found in the greatest number of participants was hookworm disease (44.8%). In this study the effectiveness of the evaluation of three feces samples is demonstrated in order to increase the percentage of diagnosed intestinal parasitoses. The visualization of a direct preparation dyed with Lugol permitted the diagnosis of 63.6% of the parasitoses, while the technique of Kato detected 56.6% of the helminth infections. CONCLUSIONS: The prevalence of geohelminths in the asymptomatic Subsaharian immigrant population is elevated. The complementary use of the microscopic study of a direct preparation dyed with Lugol and the technique of Kato increase the diagnostic performance.

Parasitosis intestinales en población inmigrante subsahariana asintomática. Gran Canaria 2000 / Intestinal parasitoses in the asymptomatic Subsaharian inmigrant population. Gran Canaria 2000

Fundamento. Realizamos un estudio prospectivo para conocer la prevalencia y el tipo de parasitosis intestinal en una cohorte de inmigrantes subsaharianos sanos llegados a Gran Canaria durante el año 2000.Métodos. Se han estudiado 348 muestras fecales de 121 inmigrantes. Se estudió un mínimo de dos y un máximo de tres muestras de cada paciente. Cada muestra fue estudiada mediante dos técnicas: visualización de una preparación directa teñida con lugol y mediante la técnica de concentración de Kato. Resultados. Un 23,1 por ciento de los pacientes presentaban parásitos patógenos en heces, observándose en 5 de ellos 2 parásitos (17,8 por ciento). Los geohelmintos (Ancylostoma duodenale/Necator americanus, Ascaris lumbricoides, Trichuris trichiura y Strongyloides stercoralis) fueron los parásitos más frecuentemente encontrados (87,9 por ciento). Específicamente la parasitosis encontrada en el mayor número de personas fue la uncinariasis (44,8 por ciento). En este estudio comprobamos la eficacia del empleo de tres muestras de heces para incrementar el porcentaje de parasitosis intestinales diagnosticadas. La visualización de una preparación directa teñida con lugol permitió el diagnóstico del 63,6 por ciento de las parasitosis, mientras que la técnica de Kato detectó el 56,6 por ciento de las helmintiasis. Conclusiones. La prevalencia de geohelmintos en la población inmigrante subsahariana asintomática es elevada. El uso complementario de la visión de una preparación directa teñida con lugol y la técnica de Kato incrementan el rendimiento diagnóstico (AU)

Mild thyroid hormones deficiency modifies benzodiazepine and mu-opioid receptor binding in rats.

The effects of a mild hypothyroidism condition on benzodiazepine (BDZ) and mu opioid receptor levels was investigated. Female Wistar rats were randomly divided into two groups: 1) hypothyroid rats (n=7), which received methimazole (60 mg/kg per day) in drinking water for four weeks, and 2) euthyroid rats (n=8), which drank only tap water. Animals were sacrificed and their brains were used for autoradiography experiments. When compared to the euthyroid group, the hypothyroid group presented reduced benzodiazepine receptor binding in medial amygdala (24%) and high mu-receptor levels in frontal (25%), sensorimotor (65%) and temporal (29%) cortices, basolateral amygdala (50%) and ventroposterior thalamic nucleus (49%). The present data suggest that alterations in BDZ and mu-receptor binding could be associated with the higher excitability observed in animals with triiodothyronine (T(3)) deficiency.

Evasion mechanisms to tumor necrosis factor alpha (TNF-alpha) of small cell lung carcinoma and non-small cell lung carcinoma cell lines: comparison with the erythroleukaemia K-562 cell line.

The tumour necrosis factor alpha (TNF-alpha) is produced by mononuclear phagocytes as a defence mechanism against malignant cells. However, these cells can evade destruction by TNF-alpha. The present study evaluates in three lung cancer cell lines (small cell carcinoma NCI-H69, adenocarcinoma A-427, squamous carcinoma SK-MES-1) and one erythroleukaemia (K-562) cell line the following evasion mechanisms: (1) inhibition of TNF-alpha production, in indirect and direct co-cultures with monocytes; (2) the expression of type I and type II receptors for TNF-alpha (TNFRI and TNFRII) by tumour cell lines, using indirect immunofluorescence and flow cytometry; (3) the sensitivity of tumour cell lines to the toxic action of recombinant human TNF-alpha (rhTNF-alpha). With the exception of cell line NCI-H69, the other tumour cell lines liberated soluble factors that inhibited TNF-alpha production in monocytes. This effect occurred even after membrane contact with the A-427 and SK-MES-1 cell lines. Erythroleukaemia K-562 cells expressed both types of receptors for TNF-alpha, whereas the NCI-H69 cells expressed only TNFRI, and the A-427 and SK-MES-1 cells expressed no receptors. Lines NCI-H69, A-427 and K-562 were insensitive to the cytotoxic action of rhTNF-alpha. In conclusion, different lung cancer cell lines may evade destruction by TNF-alpha by various mechanisms that range from blocking TNF-alpha production by monocytes to blocking the cytotoxic action of this molecule. For selecting the most effective immunotherapy, knowledge of the evasion mechanisms would be useful.

[In vitro sensitivity of Mycobacterium chelonae strains to various antimicrobial agents]. / Sensibilidad in vitro de cepas de Mycobacterium chelonae frente a diversos antimicrobianos.

The in vitro susceptibility of 32 Mycobacterium chelonae strains to 10 antimicrobial agents was determined. The sources of the different strains were: clinical samples from patients treated at the Hospital Universitario de Canarias and Hospital del Tórax (General and Chest facilities) and from environmental sources (water supply, sewage, swimming pools and the sea). The susceptibility tests were performed by a broth microdilution method (Mueller-Hinton Broth). The results showed amikacin as the most effective antimicrobial agent against M. chelonae isolates, then ofloxacin and cefoxitin. However no statistical difference was detected among them. The least effective was imipenem, followed by ciprofloxacin and norfloxacin.

[A microbiological and physicochemical analysis of the water in swimming pools on the island of Tenerife]. / Análisis microbiológico y fisicoquímico del agua de piscinas de la isla de Tenerife.

BACKGROUND: A microbiological and physiochemical analysis has been made from 60 samples of water from two swimming pools in Santa Cruz de Tenerife in order to know the hygienic condition and to establish the most adequate microbiological indicators. The water of the two swimming pools has a different origin: sea water (Swimming pool B) and public supply (Swimming pool A), and so, different processings are used. METHODS: The analytical methodology was based on the Spanish current day regulations for the control of drinkable waters for public use, as well as on the methods the American Public Health Association recommends. RESULTS: There have been found differences between one swimming pool and the other, depending basically on the water characteristics and the processings used to treat it; there exists a greater microbiological contamination in the samples from the swimming pool B. It has been proved that medium R2A is better than medium P.C.A. to recount total mesophilic aerobes in both swimming pools. CONCLUSIONS: The isolation of St. aureus species in samples from the swimming pool B makes of it a possible microbiological indicator for the hygienic control of swimming pool waters of marine origin. Likewise, the presence of mycobacterium species in samples of the swimming pool A confirms its resistance to concentrations of growth inhibitors of free chlorine.

[Health instruction in adult education as instrument for community participation. Analysis of an experiment in La Nora (Murcia)]. / La formación sanitaria en la educación de adultos como instrumento para la participación comunitaria. Análisis de una experiencia en La Nora (Murcia).

AIM: The main aim of this work is to demonstrate the possibility of establishing stable contacts between the PC study and citizens' groups, in order to promote Health Education. The experience of Adult Education in a Health Centre, initiated by its Consejo de Salud (Health Council), was analysed. DESIGN: The study's methodology is of Participatory Research based on an earlier descriptive analysis, which had followed the educational input. PLACE: It takes place in a PCC and is a Community-based activity. PARTICIPANTS: The PC study, Adult Education teachers, the Social Health Department of the Faculty of Medicine and 136 adult students from nine villages in the rural area of La Nora (Murcia), took part in the study. ACTIVITIES: Essentially to develop a programme of Health Instruction within Adult Education, in order to encourage Community Participation. RESULTS: They focus on checking the effect of the programme on all the groups concerned and analysing the characteristics of the adult student body. CONCLUSIONS: The most important have been the generally positive feelings about the experiment and thus the possibility of tackling new ones. It was important that the study had been the fruit of a programme of Community Participation, with the Health Centre as the point of reference.