Proposed validation stages for MPs extraction from edible mussels (Mytilus galloprovincialis).

The potential presence of microplastics (MPs) in seafood products presents significant health concerns, demanding the adoption of standardized and validated methodologies. In this study, we introduce a validated method and an innovative technique for extracting MPs from mussels using an oxidizing agent, Corolase enzyme, and a surfactant, thus eliminating the need for mechanical agitation. Evaluation of the extraction process focused on three critical parameters: recovery percentage, repeatability, and chemical integrity, along with color stability. To ensure precision and reliability, low-density infrared spectroscopy (LDIR) was employed to analyze the effect of spectrum quality (Q). Ultimately, this methodology was applied to identify MPs in commercial mussels, with results showcasing the viability of the proposed validation stages for MPs extraction, maintaining MPs integrity with high recovery percentages.

Obtention of biochar-Fe/Ce using Punica granatum with high adsorption of ampicillin capacity.

This research presents the obtaining of a biochar (CB) from the use of pomegranate peel (Punica granatum) conditioned with iron and cerium nanoparticles (C-Fe/Ce), as well as its characterization by SEM (Scanning Electronic Microscopy), FTIR (Fourier Transform Infrared Spectrometry), TGA (Thermogravimetric analysis), EDS (Energy Dispersive Spectroscopy), XPS (X-Ray Photoelectron Spectroscopy) and evaluation of the adsorption capacity of ampicillin (AMP) in aqueous phase at 20, 30 and 40 °C. The maximum adsorption capacity for CB was 18.97 mg g-1 and for C-Fe/Ce, 27.61 mg g-1 at pH of 7, observing that with increasing temperature, the sorption capacity decreases in both materials, the experimental data was fitted to various mathematical models and the best fit was the pseudo-second order model for the kinetics, whilst for the adsorption isotherms the best fit was with the Langmuir model, indicating that the adsorption process is carried out in a monolayer on a homogeneous surface, through a chemisorption process. According to the thermodynamic parameters this process is carried out through an exothermic reaction. The results obtained indicate that both materials are suitable for the removal of AMP in the aqueous phase and that they can be reused up to 5 times.

Obtention of biochar-Ca nanoparticles using Citrus tangerina׃ A morphological, surface and study remotion of Aflatoxin AFB1.

This work presents the formation of biochar with calcium nanoparticles (NPsCa) in function of pyrolysis time (C10, C30, C60, C120 and C180 min) using the Citrus tangerina peel and their evaluation in the remotion of Aflatoxin B1 (AFB1) in aqueous phase. Firstly, the Citrus tangerina was studied by Thermogravimetric analysis to determine the optimal temperature (TGA), obtaining a result of 600 °C. The biochar (NPsCa) were characterized by Scanning Electronic Microscopy (SEM) and Energy Dispersive Spectroscopy (EDS), as well as surface properties including the identification of functional groups by Fourier Transform Infrared Spectrometry (FTIR), and energetic states through the X-Ray Photoelectron Spectroscopy (XPS). The adsorption studies were carried out on the different materials and later, the experimental data was adjusted to different mathematical models, obtaining the best fit of the kinetic data to the Ho-McKay model, whilst the adsorption isotherms were adjusted to the model of Langmuir, which indicates that the Aflatoxin B1 adsorption process is carried out through a monolayer chemisorption process with maximum sorption capacities (qm) ranging between 15.72 and 63.22 µg g-1 with the 180th minute being the adequate time to obtain the carbon with the best surface properties and the best adsorption capacity. Additionally, it was observed that each material can be reused up to five times in accordance with the results from the reuse cycles.

Tromboprofilaxis en pacientes médicos y quirúrgicos: resultados de un estudio multicéntrico realizado en hospitales de la Ciudad de México / Thromboprophylaxis in medical and surgical patients: results of a multicenter study in hospitals of Mexico City

Resumen: ANTECEDENTES: la enfermedad tromboembólica venosa es una complicación que puede manifestarse durante o después de la hospitalización. Existen pocos antecedentes en nuestro país que evalúan el comportamiento médico en este tema. OBJETIVO: conocer la prescripción relacionada con el tipo, duración y posibles causas de la omisión de tromboprofilaxis en pacientes hospitalizados. MATERIAL Y MÉTODO: estudio descriptivo, transversal y no probabilístico en el que de septiembre a noviembre de 2016 se evaluaron médicos de Medicina Interna, Cirugía General, Terapia Intensiva y Urgencias. Se recolectaron datos por cuestionario y presentación de resultados a través de estadística descriptiva. También se evaluó la duración de la prescripción y la dosis administrada. RESULTADOS: se encuestaron 556 médicos adscritos, 14 jefes de servicio y 234 residentes total: 804 de siete hospitales de la Ciudad de México pertenecientes al sistema de salud. El 30% refirió que su hospital cuenta con un programa de tromboprofilaxis; 97.7% la considera segura y 1.2%, riesgosa. El 96% respondió que prescribe tromboprofilaxis en sus pacientes; 592 74% utilizan alguna escala de previsión clínica de enfermedad tromboembólica venosa. El 71% recomienda heparina de bajo peso molecular para tromboprofilaxis y 0.74% administra anticoagulantes orales de nueva generación. CONCLUSIONES: la enfermedad tromboembólica venosa es potencialmente prevenible; sin embargo, la prescripción muestra oportunidades de mejoría en aspectos de farmacología.

Abstract: BACKGROUND: Venous thromboembolic disease VTE is a complication that may occur during or after hospitalization. There are few antecedents in our country that evaluate the medical behavior in this subject. OBJECTIVE: To know the prescription related to type, duration and possible causes for omission of thromboprophylaxis in hospitalized patients. MATERIAL AND METHOD: A descriptive, transversal and non-probabilistic study was done, in which from September to November 2016 physicians of Internal Medicine, General Surgery, Intensive Care and Urgency were evaluated through a data collection by questionnaire and presentation of results through descriptive statistics. We also evaluated duration of prescription and dose administered. RESULTS: A total of 556 seconded physicians, 14 service heads, and 234 residents 804 in total were surveyed in seven hospitals in Mexico City belonging to the health system. Thirty percent reported that their hospital has a thromboprophylaxis program; 97.7% consider it safe and 1.2% risky; 96% responded that they prescribe thromboprophylaxis in their patients; 592 73.6% used some clinical prediction scale for VTE; 71% recommended low molecular weight heparin for thrombo prophylaxis and 0.74% administered new generation oral anticoagulants. CONCLUSIONS: Venous thromboembolic disease is potentially preventable; however, prescription shows opportunities for improvement in aspects of pharmacology.

Effects of melatonin and gonadal androgens on cell proliferation in the pituitary of viscachas (Lagostomus maximus maximus).

OBJECTIVES: Melatonin and androgens are involved in the regulation of cell proliferation. However, effects of these hormones on pituitary pars distalis (PD) of male viscachas is not fully understood. In the present study, we analysed melatonin and gonadal androgens' effects on proliferating cell nuclear antigen (PCNA) expression. MATERIALS AND METHODS: Pituitary glands from foetuses, immature individuals, prepubertal individuals and adult viscachas during their reproductive cycle, after melatonin administration and after castration, were used. PCNA-ir cells were detected by immunocytochemistry and morphometrically quantified using image analysis. RESULTS: Total percentage of PCNA-ir cells varied seasonally in the adult pituitary, with maximum values during the reproductive period and minima during gonadal regression periods. Percentages of PCNA-ir cells increased after melatonin administration, whereas it decreased after castration. Caudal end and ventral regions were the PD zones which were most affected by seasonal variations and castration. PCNA expression was highest in foetal pituitary from midpregnancy. Numbers of PCNA-ir cells decreased during sexual maturity. CONCLUSIONS: Our results demonstrate the effect of gonadal androgens on cell proliferation during the reproductive period and sexual maturity of these animals. Exogenous melatonin increased PD cell proliferation in adults. Thus, these hormones seem to be involved in different mechanisms that regulate cell renewal of PD in this seasonally breeding rodent.

Características Antropométricas por Posición de Juego en Mujeres Futbolistas Chilenas de la Región de Valparaíso, Chile / Anthropometric Attributes by Playing Position in Chilean Female Football Players From the Valparaiso Region, Chile

Participaron del estudio 76 mujeres futbolistas de la región de Valparaíso, las edades fluctuaron entre los 18 y 30 años. Fueron evaluados los equipos femeninos profesionales de los clubes Everton, Santiago Wanderers y San Luis de Quillota, las selecciones de la universidades de Valparaíso, Técnica Federico Santa María y Universidad Viña del Mar. Las posiciones de juego fueron distribuidas en arqueras (n= 8), defensas (n= 25), volantes (n= 24) y delanteras (n= 18). Para la evaluación de la composición corporal se utilizó el protocolo establecido por la International Society for the Advancement of Kinanthropometry. Para determinar el somatotipo de las futbolistas fue utilizado el modelo de Heath & Carter. Se fraccionó el peso corporal total a través del método pentacompartimental diseñado por Kerr. Los resultados demuestran un somatotipo promedio mesomorfo endomorfo, la distribución por equipos evidencia diferencias significativas en el mesomorfismo entre los equipos Everton y Universidad Viña del Mar (p<0,014). Entre las posiciones arquera y delantera existieron diferencias significativas en las variables peso (p<0,030) y endomorfia (p<0,050). No existieron diferencias en el porcentaje de tejido adiposo, tejido muscular, sumatoria de pliegues y estatura por posición de juego. En lo que respecta a la distribución por posición de juego, se evidencia un somatotipo meso endomorfo en las posiciones arquera y defensa, en las posiciones volantes y delanteras se aprecia un somatotipo mesomorfo endomorfo, esto demuestra una diferenciación del somatotipo entre posiciones de juego defensivas y ofensivas encontrando un mayor predominio de la endomorfia en las posiciones defensivas en comparación con las de ataque. Según el método SANOVA se concluye que las futbolistas evaluadas en este estudio presentaron características antropométricas similares, no habiendo diferencias significativas entre equipos universitarios y profesionales, ni por posición de juego.

Seventy-six female football players from the Valparaiso Region. Players´ age fluctuated between 18 and 30 years participated in this research. Female professional teams from Everton, Santiago Wanderers and San Luis de Quillota clubs, as well as the teams from Federico Santa María Technical University and Viña del Mar University were evaluated. Playing positions were: goalkeepers (n= 8), defenders (n= 25), attacking midfielders (n= 24) and strikers (n= 18). To measure body composition the protocol established by the International Society for the Advancement of Kinanthropometry was used, according to the restricted profile described by Drinkwater and Norton & Olds. The Heath and Carter method was used to determine the somatotype of the female football players. Total body mass was divided using Kerr´s Five-Way Fractionation method. Results show an average somatotype of mesomorph and endomorph. In the distribution by teams, the results showed significant differences of mesomorph between the Everton Club and the Viña del Mar University (p<0.014). Between the goalkeepers and the strikers there were significant differences regarding weight (p<0.030) and endomorph (p<0.050). No differences in the percentage of adipose tissue, muscle tissue, the sum of folds and height in relation to playing position were found. Regarding the distribution by playing position, the results showed a meso-endomorph somatotype for the goalkeepers and defenders, and a mesomorph endomorph somatotype for the attacking midfielders and strikers. This reveals a differentiation of somatotypes between offensive and defensive playing positions, finding a higher prevalence of the endomorph somatotype in defensive playing positions compared to the attack positions. Using the SANOVA method, the study concludes that the anthropometric attributes of the female football players evaluated are similar, with no significant differences between university teams and professional teams or by playing position.

Perfil antropométrico por posición de juego en handbolistas chilenos / Anthropometric profile in Chilean handball players according to playing position

El objetivo fundamental de la presente investigación fue determinar el perfil antropométrico y su relación con la capacidad de salto en jugadores de balonmano varones de la región de Valparaíso y de la Selección Chilena, esto en relación a su posición en el campo de juego. Se valoraron 74 jugadores de la categoría cadetes, cuyas edades fluctuaron entre los 14 y los 16 años, pertenecientes a los equipos: Club Italiano Villa Alemana, Club Italiano Quillota, Club Luterano, Club Viña del Mar, Club San José y Selección Chilena. Los resultados arrojaron que en cuanto a las variables antropométricas, la Selección Chilena y el Club Italiano Villa Alemana, son los que poseen los parámetros que más se asemejan a los requeridos a nivel competitivo dentro de esta categoría. Al hacer referencia a las variables antropométricas se estimó que, en todos los grupos estudiados, la masa adiposa se relacionó negativamente con la altura de salto alcanzada. Mientras que la masa muscular presentó una alta correlación con el rendimiento en salto en la mayoría de los equipos. Los índices de correlación evidenciaron que un menor porcentaje de masa grasa y mayor porcentaje de masa muscular favorecen la altura de salto alcanzada en todas las posiciones de juego. Queda de manifiesto que la relación masa adiposa y masa muscular es un indicador importante a la hora de determinar el rendimiento en la capacidad de salto en deportistas con características similares a las de este estudio.

The primary purpose of this research was to determine the relationship between the anthropometric profile and jump capacity of male handball players from the Fifth Region of Chile and the National Handball Team and their specific position in the playing field. In the evaluation 74 handball players participated from the following teams: Club Italiano Villa Alemana, Club Italiano Quillota, Club Luterano, Club Viña del Mar, Club San José and the National Handball Team. Participants were in the cadet category aged 14 ­ 16. The results showed that within anthropometric variables, players from the Chilean Handball Team and the Club Italiano Villa Alemana are the closest to fulfilling all the criteria required to reach high competitive levels in this category. In reference to anthropometric variables, fat mass proved to be negatively related to jump height reached in all groups tested, while muscle mass presented significant correlation with the jump capacity in most of the teams. Regarding the somatotype, results obtained agree with the theoretical referents. These establish that handball player's somatotype is more likely to be mesomorph. The correlation indexes demonstrate that a lower fat mass percentage and a higher muscle mass percentage enhance the jump capacity in all playing positions. It is clear now that fat mass and muscle mass are important indicators when determining the jump capacity performance in players with similar characteristics of the ones in this study. This research is important in setting comparative parameters in the selection process and sport specialization regarding anthropometric characteristics and jump capacity according to specific position of handball players in the cadet category.

Value of superficial cultures for prediction of catheter-related bloodstream infection in long-term catheters: a prospective study.

Cultures taken from the skin and from the hubs of short-term central venous catheters can help us to predict catheter-related bloodstream infections (C-RBSIs). The value of these cultures for such predictions has not been assessed in long-term catheters. Our objective was to assess the value of superficial cultures for the prediction of C-RBSI among patients with long-term catheters. Over a 2-year period, we prospectively obtained cultures from the skin overlying reservoir ports (group A) and from the skin insertion site and hubs of all tunneled catheters (group B). This routine was performed by vascular and interventional radiologists immediately before catheter removal (irrespective of the reason for withdrawal). Swabs were processed semiquantitatively. Catheter tips from both groups were cultured using Maki's semiquantitative technique and sonication. We also performed cultures of the reservoir ports at different sites. C-RBSI was defined as the isolation of the same species of microorganism(s) both in the colonized catheter and in at least 1 peripheral blood culture. We included 372 catheters (group A, 223; group B, 149) during the study period. The catheter colonization rate was 23.4% (87/372), and 28 patients had C-RBSI. Validity index values for the capacity of surface cultures to predict C-RBSI in groups A and B were, respectively, as follows: sensitivity, 23.5% and 45.5%; specificity, 59.7% and 63.0%; positive predictive value, 4.6% and 8.9%; and negative predictive value, 90.4% and 93.5%. Superficial cultures of patients with long-term catheters could help us to rule out the catheter as the portal of entry of bloodstream infections. Superficial cultures (from skin and hubs) proved to be a useful conservative diagnostic tool for ruling out C-RBSI among patients with long-term tunneled catheters and totally implantable venous access ports.

Use of universal 16S rRNA gene PCR as a diagnostic tool for venous access port-related bloodstream infections.

Amplification of the universal 16S rRNA gene using PCR has improved the diagnostic yield of microbiological samples. However, no data have been reported on the reliability of this technique with venous access ports (VAPs). We assessed the utility of 16S rRNA PCR for the prediction of VAP-related bloodstream infection (VAP-RBSI). During a 2-year period, we prospectively received all VAPs removed by interventional radiologists. PCR and conventional cultures were performed using samples from the different VAP sites. We compared the results of PCR with those of conventional culture for patients with confirmed VAP-RBSI. We collected 219 VAPs from 219 patients. Conventional VAP culture revealed 15 episodes of VAP-RBSI. PCR revealed a further 4 episodes in patients undergoing antibiotic therapy which would have gone undetected using conventional culture. Moreover, it had a negative predictive value of 97.8% for the prediction of VAP-RBSI when it was performed using biofilm from the internal surface of the port. In conclusion, universal 16S rRNA PCR performed with samples from the inside of VAPs proved to be a useful tool for the diagnosis of VAP-RBSI. It increased detection of VAP-RBSI episodes by 21.1% in patients undergoing antibiotic therapy whose episodes would have gone undetected using conventional culture. Therefore, we propose a new application of 16S rRNA PCR as a useful tool for the diagnosis of VAP-RBSI in patients receiving antibiotic therapy.

Synthesis, characterization and adsorptive properties of carbon with iron nanoparticles and iron carbide for the removal of As(V) from water.

This manuscript presents the synthesis of carbon modified with iron nanoparticles (CFe) and iron carbide (CarFe) from the pyrolyzed crown leaves of pineapple (Ananas comosus) treated with iron salts. The materials that were obtained were used for the removal of As(V) from aqueous media. The carbonaceous materials were characterized by Scanning Electron Microscopy (SEM), Transmission electron microscopy (TEM), X-ray diffraction (XRD), X-Ray Photoelectron Spectroscopy (XPS) and Mossbauer Spectroscopy. The specific area (BET), number site density and point of zero charge (pH(pzc)) were also determined. The kinetic parameters were obtained by fitting the experimental data to the pseudo-first-order and pseudo-second-order models. Different isotherm models were applied to describe the As(V) adsorption behavior. The kinetics of As(V) sorption by CFe and CarFe was well defined for the pseudo-second-order model (R(2) = 0.9994 and 0.999, respectively). The maximum As(V) uptake was 1.8 mg g(-1) for CFe and 1.4 mg g(-1) for CarFe. The results obtained indicated that both materials are equally useful for As(V) sorption. The As(V) experimental isotherm data were described by the Freundlich model for CFe and CarFe.

Tratamiento de la infección recalcitrante de cadera mediante colgajo de músculo vasto lateral / Treatment of a recalcitrant hip infection with a vastus lateralis muscle flap

Introducción. La infección recalcitrante de cadera tras artroplastia es una complicación de difícil tratamiento para el cirujano ortopédico. El objetivo de este estudio es evaluar los resultados de estas infecciones de cadera recalcitrantes que hemos tenido en nuestro Servicio tratadas con el colgajo de vasto externo. Material y métodos. Estudio descriptivo retrospectivo de 5 pacientes con infecciones profundas de cadera mediante trasposición de colgajo del músculo vasto lateral. Edad media: 70,5 años. Tiempo medio de seguimiento: 30 meses (rango, 25-34 meses). Previamente todos los pacientes habían sido sometidos a distintos procedimientos quirúrgicos mayores (media de 3,7 procedimientos previos). Todos presentaban infecciones polimicrobianas previas a la cirugía. Se estudió los agentes patógenos involucrados mediante cultivo de la fístula, la evolución de la herida, así como controles analíticos, incluidos la proteína C-reactiva (PCR). Resultados. Se consiguió la curación de la herida en los 5 pacientes intervenidos, sin necesidad de realizar ningún otro procedimiento posterior ni aparición de fístula ni otros signos flogóticos de infección. La PCR se normalizó al mes de la intervención y no hubo morbi-mortalidad relacionada con la técnica quirúrgica. Conclusión. En nuestra experiencia, el colgajo de músculo vasto lateral como tratamiento para la infección profunda recalcitrante tras artroplastia de cadera ha presentado buenos resultados, siempre enmarcado dentro de un adecuado tratamiento antibiótico y desbridamiento quirúrgico, consiguiendo la curación de la herida y normalización de la PCR (AU)

Background. Recalcitrant hip infection after arthroplasty presents a reconstructive challenge to orthopedic surgeons. The aim of this study is to evaluate the results with a vastus lateralis muscle flap used to treat these recalcitrant hip infections in our Department. Material and methods. A retrospective descriptive study was conducted on five patients with deep hip infections by transposition of the vastus lateralis muscle flap. Average age: 70.5 years. Mean follow-up: 30 months (range, 25-34 months). All patients had previously undergone other major surgical procedures (mean of 3.7 previous procedures). All had multiple microbial infections before surgery. The pathogens involved using cultures of the fistula, the outcome of the wound and laboratory results, including C-reactive protein (CRP), were analysed. Results. Healing was achieved in the five patients who underwent surgery without requiring any further procedures or inflammatory signs of infection. CRP returned to normal one month after surgery, and there was no morbidity or mortality related to surgical technique. Conclusion. In our experience, the vastus lateralis muscle flap as a treatment for recalcitrant deep infection after arthroplasty has presented good results, provided there is appropriate antibiotic therapy and surgical debridement, thus achieving wound healing and a return to normal of the CRP (AU)

Effect of the pH and temperature on the biosorption of lead(II) and cadmium(II) by sodium-modified stalk sponge of Zea mays.

OBJECTIVE: The present work was carried out to investigate the effects of temperature, initial pH, initial concentration, and contact time on the biosorption of lead (Pb) and cadmium (Cd) by modified stalk sponge of Zea mays using a batch technique. METHODS: The biomass was chemically modified with a 0.1 M NaCl solution. The lead and cadmium sorption process was evaluated at 20°C, 30°C, 40°C, and 50°C. RESULTS: The results showed that the modified stalk sponge of Z. mays had a good capacity for biosorption of Pb(II) and Cd(II). The kinetic behavior was described by the pseudo-second-order model for both metallic species. The experimental isotherms obtained at different temperatures were fit with Langmuir and Freundlich models. Thermodynamic parameters ΔH(0) and ΔS(0) were calculated using the van't Hoff equation, and the results show that Pb(II) and Cd(II) sorption by modified stalk sponge of Z. mays is an exothermic and spontaneous process.

[Treatment of a recalcitrant hip infection with a vastus lateralis muscle flap]. / Tratamiento de la infección recalcitrante de cadera mediante colgajo de músculo vasto lateral.

BACKGROUND: Recalcitrant hip infection after arthroplasty presents a reconstructive challenge to orthopedic surgeons. The aim of this study is to evaluate the results with a vastus lateralis muscle flap used to treat these recalcitrant hip infections in our Department. MATERIAL AND METHODS: A retrospective descriptive study was conducted on five patients with deep hip infections by transposition of the vastus lateralis muscle flap. Average age: 70.5 years. Mean follow-up: 30 months (range, 25-34 months). All patients had previously undergone other major surgical procedures (mean of 3.7 previous procedures). All had multiple microbial infections before surgery. The pathogens involved using cultures of the fistula, the outcome of the wound and laboratory results, including C-reactive protein (CRP), were analysed. RESULTS: Healing was achieved in the five patients who underwent surgery without requiring any further procedures or inflammatory signs of infection. CRP returned to normal one month after surgery, and there was no morbidity or mortality related to surgical technique. CONCLUSION: In our experience, the vastus lateralis muscle flap as a treatment for recalcitrant deep infection after arthroplasty has presented good results, provided there is appropriate antibiotic therapy and surgical debridement, thus achieving wound healing and a return to normal of the CRP.

How should long-term tunneled central venous catheters be managed in microbiology laboratories in order to provide an accurate diagnosis of colonization?

Guidelines recommend the roll-plate technique for short-term central venous catheter (CVC) tip cultures. However, the issue of whether the roll-plate technique is better than the sonication method for long-term CVCs remains unresolved. In addition, no data are available for predicting the value of direct Gram staining in anticipating catheter colonization or catheter-related bloodstream infection (CRBSI) in these long-term CVCs. Our objectives were to compare the roll-plate technique and the sonication method and to define the validity values of Gram staining for the prediction of colonization and CRBSI in patients with long-term tunneled CVCs. During the study period, all tunneled CVCs removed at our institution were prospectively and routinely sent to the microbiology laboratory for Gram staining (first) and tip culture (the Maki technique and sonication, in a random order). We received 149 tunneled CVCs, 39 (26.2%) of which were colonized and 11 (7.4%) of which were associated with CRBSI. Overall, the roll-plate method detected 94.9% of the colonized catheters, whereas sonication detected only 43.6% (P < 0.001). The validity values of Gram staining for the detection of colonization and CRBSI were as follows: a sensitivity of 35.9% to 60.0%, a specificity of 100% to 94.2%, a positive predictive value of 100% to 42.9%, and a negative predictive value of 81.5% to 97.0%. The roll-plate technique proved to be better than sonication for the detection of bacteria in long-term tunneled CVCs. Gram staining of the tips of tunneled CVCs can anticipate a positive culture and rule out CRBSI. In our opinion, direct Gram staining should be incorporated into routine microbiological assessments of long-term catheter tips.

Biosorption of lead by maize (Zea mays) stalk sponge.

This study investigated the removal of Pb(II) from aqueous solutions by a maize (Zea mays) stalk sponge. Equilibrium and kinetic models for Pb(II) sorption were developed by considering the effect of the contact time and concentration at the optimum pH of 6 +/- 0.2. The Freundlich model was found to describe the sorption energetics of Pb(II) by Z. mays stalk sponge, and a maximum Pb(II) loading capacity of 80 mg g(-1) was determined. The kinetic parameters were obtained by fitting data from experiments measuring the effect of contact time on adsorption capacity into pseudo-first and second-order equations. The kinetics of Pb(II) sorption onto Z. mays biosorbent were well defined using linearity coefficients (R(2)) by the pseudo-second-order equation (0.9998). The results obtained showed that Zea may stalk sponge was a useful biomaterial for Pb(II) sorption and that pH has an important effect on metal biosorption capacity.

Interaction between U(VI) and SrTiO3 surfaces versus temperature.

The purpose of this work is the study of the interaction mechanisms between U(VI) ions and SrTiO(3) surfaces as a function of pH and temperature (25, 50, 75 and 90 degrees C) by coupling thermodynamic and spectroscopic approaches. First, the reactivity towards U(VI) for both surface sites of the strontium titanate ([triple bond]Ti-O and [triple bond]Sr-O) has been investigated as a function of the temperature. The N(2)-BET specific area was measured: 2.4+/-0.2 m(2)g(-1). The surface site density has been determined from potentiometric titrations (6 sites/nm(2) for each site [triple bond]Ti-O and [triple bond]Sr-O). The potentiometric titration data have been simulated, for each temperature, using the FITEQL 4.0 software and the constant capacitance model, taking into account both protonation of the [triple bond]Sr-OH surface sites and deprotonation of the [triple bond]Ti-OH ones (one pK model). The intrinsic strontium protonation constant increases with an increasing temperature, while the titanate deprotonation one decreases. Moreover, both enthalpy and entropy changes corresponding to the surface acid-base reactions have been evaluated using the van't Hoff relation. The uranium(VI) ions are sorbed onto SrTiO(3) surfaces in the 0.5-5.0 pH range with an initial cation concentration equal to 10(-4) M. The U(VI) surface complexes were identified by using time-resolved laser-induced fluorescence spectroscopy (TRLFS). For all the studied samples, the fluorescence spectra and the corresponding lifetime values do not change with the pH and the temperature. Two U(VI) complexes sorbed onto SrTiO(3) were detected and the corresponding lifetimes are 60+/-5 and 12+/-2 micros whatever the temperature (25, 50, 75 and 90 degrees C). The sorption edges were simulated with the FITEQL 4.0 code. The sorption equilibrium constants of the U(VI)/SrTiO(3) system between 25 and 90 degrees C were obtained with the constant capacitance model (CCM), considering two reactive surface sites. According to the spectroscopic characterization, two types of surface complexes, namely [([triple bond]SrOH)([triple bond]TiOH)UO(2)](2+) and [([triple bond]TiOH)([triple bond]TiO)UO(2)](2+), were considered. Finally, enthalpy (Delta(r)H(o)) and entropy (Delta(r)S(o)) changes were calculated from the temperature-dependent sorption constants, by the application of the van't Hoff formalism. The formation of the [([triple bond]SrOH)([triple bond]TiOH)UO(2)](2+) surface complex was found to present an endothermic character associated to an increase in the disorder of the system. On the contrary, the formation of the [([triple bond]TiOH)([triple bond]TiO)UO(2)](2+) surface complex led to an exothermic process with only a slight increase in the disorder of the system.

Obtención de Echinococcus granulosus en caninos infectados experimentalmente con protoescólices de quistes hidatídicos / Obtaining of Echinococcus granulosus in experimentally infected dogs with protoscolices of hydatid cysts

El presente estudio tuvo por objetivo reproducir experimentalmente el ciclo biológico del Echinococcus granulosus en perros. Se utilizó 12 perros (4-50 meses de edad) que fueron infectados experimentalmente con 80,000 a 308,000 protoescólices de quistes hidatídicos de pulmón e hígado de ovinos procedentes de Junín y Ayacucho. Los perros se sacrificaron 28 a 39 días post infección (p.i). El intestino delgado se dividió en tres porciones iguales (anterior, media y posterior). Los parásitos fueron separados del intestino y contados. Además, en tres perros se determinó el grado de dispersión del parásito en las tres porciones del intestino delgado. Ocho de los 12 perros se infectaron, recolectándose entre 1,299 a 65,000 parásitos adultos por perro. Los animales sacrificados el día 28 p.i resultaron negativos, mientras que ocho de los nueve perros sacrificados a partir del día 30 p.i. resultaron positivos. El sitio de mayor predilección del parásito fue la porción media del intestino delgado. Se demostró que la inoculación de protoescólices de quistes hidatídicos ovinos, vía oral, es efectiva para para reproducir el ciclo biológico del E. granulosus en perros.

The objective of the present study was to experimentally reproduce the biological cycle of Echinococcus granulosus in dogs. Twelve dogs, 4-50 months old, were infected with 80,000-308,000 protoscolices recovered from lung and liver hidatyd cysts in sheep reared in the central highlands of Peru. Dogs were slaughtered 28-39 days post infection (p.i) and the small intestine was divided in three equal portions (anterior, medium, and posterior) and parasites were counted. The location of parasites in the three portions of intestine was recorded in three dogs. Eight out of 12 dogs resulted positive to the infection and the number of parasites varied from 1,299 till 65,000 per dog. Animals slaughtered on the 28th p.i day resulted negative. The preferred site for parasites was the medium portion of the small intestine. It was shown that the oral inoculation of protoscolices from sheep hydatic cysts was effective to reproduce the biological cycle of the E. granulosus in dogs.

Genetic characterization, pathogenicity, and protection studies with an avian adenovirus isolate associated with inclusion body hepatitis.

An avian adenovirus (AAV) was isolated from liver samples of two 2-wk-old broiler-breeder flocks obtained from grandparents vaccinated at 10 and 17 wks of age with an autogenous inactivated vaccine containing the European AAV 8 (8565 strain) and 11 (1047 strain) serotypes (AAV8/11 vaccine). Affected broiler-breeders exhibited clinical signs and macroscopic and microscopic lesions associated with inclusion body hepatitis (IBH). The isolated adenovirus, identified as Stanford, was molecularly characterized as European serotype 9. The pathogenicity of the Stanford strain was confirmed after inoculation of specific-pathogen-free (SPF) chickens at 1-7 days of age, causing 100% and 20% mortality, respectively. The level of protection against IBH was evaluated in two broiler-breeder progenies from AAV 8/11-vaccinated grandparent flocks and a commercial broiler flock by challenge at 1 or 7 days of age with the AAV 8 and 11 serotypes and/or the Stanford strain. The broiler-breeder progenies and the commercial broiler flock exhibited protection against IBH after challenge. No significant differences in mean body weights were observed at 3 wk of age in any of the evaluated groups. We conclude that broiler-breeder progenies from 30- to 50-wk-old grandparents vaccinated with the AAV 8/11 vaccine were adequately protected against challenge with the AAV 8 and 11 serotypes and the Stanford strain.

Expanded PTFE-covered stent-grafts in the treatment of transjugular intrahepatic portosystemic shunt (TIPS) stenoses and occlusions.

BACKGROUND: We evaluated the efficacy of the VIATORR endoprosthesis for the management of transjugular intrahepatic portosystemic shunt (TIPS) dysfunction. METHODS: Twelve consecutive patients (10 men and two women, mean age 52.7 years) with recurrent TIPS dysfunction underwent TIPS revision with use of the VIATORR endoprosthesis. Nine patients were asymptomatic and three patients had developed recurrent variceal bleeding. All patients had previous shunt revisions (mean 2.1 revisions per patient) with angioplasty or bare stents. Follow-up included clinical assessment, Doppler ultrasound, and portal venography. RESULTS: TIPS revision was successful in all patients, without complications. The mean portosystemic pressure gradient decreased from 16.8 +/- 2.7 mmHg to 6.5 +/- 2.6 mmHg. Hemostasis was achieved in all three patients who had recurrent variceal bleeding at the time of the procedure. Mean follow-up was 21.9 +/- 10.7 months. In two patients TIPS dysfunction occurred at 14 and 30 months after stent-graft placement, respectively. The primary patency rates were 100% after 12 months and 88.8% after 24 months. Two patients (16.6%) developed encephalopathy after stent graft placement. CONCLUSION: TIPS revision using the VIATORR endoprosthesis appears to be an effective and durable method to control shunt dysfunction.