RESUMEN
Manganese (Mn), despite being a trace element necessary in small quantities for the correct functioning of the organism, at higher concentrations can induce health disorders, mainly in motor and cognitive functions, even at levels found in non-occupational environments. For this reason, US EPA guidelines define safe reference doses/concentrations (RfD/RfC) for health. In this study, the individualised health risk of exposure to Mn through different media (air, diet, soil) and routes of entry into the organism (inhalation, ingestion and dermal absorption) was assessed according to the procedure defined by the US EPA. Calculations related to Mn present in ambient air were made on the basis of data obtained from size-segregated particulate matter (PM) personal samplers carried by volunteers recruited in a cross-sectional study conducted in the Santander Bay (northern Spain), where an industrial source of airborne Mn is located. Individuals residing in the vicinity of the main Mn source (within 1.5 km) were found to have a hazard index (HI) higher than 1, indicating that there is a potential risk for these subjects to develop health alterations. Also, people living in Santander, the capital of the region, located 7-10 km from the Mn source, may have some risk (HI > 1) under some wind conditions (SW). In addition, a preliminary study of media and routes of entry into the body confirmed that inhalation of PM2.5-bound Mn is the most important route contributing to the overall non-carcinogenic health risk related to environmental Mn.
Asunto(s)
Contaminantes Atmosféricos , Manganeso , Humanos , Manganeso/análisis , Monitoreo del Ambiente/métodos , Estudios Transversales , Exposición a Riesgos Ambientales/análisis , Material Particulado/análisis , Medición de Riesgo , Contaminantes Atmosféricos/análisisRESUMEN
The environmental exposure to trace metal(loid)s (As, Cd, Cu, Fe, Mn, Pb, and Zn) was assessed near a ferromanganese alloy plant using filters from personal particulate matter (PM) samplers (bioaccessible and non-bioaccessible fine and coarse fractions) and whole blood as short-term exposure markers, and scalp hair and fingernails as long-term biomarkers, collected from volunteers (n = 130) living in Santander Bay (northern Spain). Bioaccessible and non-bioaccessible metal(loid) concentrations in coarse and fine PM from personal samplers were determined by ICP-MS after extraction/digestion. Metal(loid) concentration in biomarkers was measured after alkaline dilution (whole blood) and acid digestion (fingernails and scalp hair) by ICP-MS as well. Results were discussed in terms of exposure, considering the distance to the main Mn source, and sex. In terms of exposure, significant differences were found for Mn in all the studied fractions of PM, As in whole blood, Mn and Cu in scalp hair and Mn and Pb in fingernails, with all concentrations being higher for those living closer to the Mn source, with the exception of Cu in scalp hair. Furthermore, the analysis of the correlation between Mn levels in the studied biomarkers and the wind-weighted distance to the main source of Mn allows us to conclude that scalp hair and mainly fingernails are appropriate biomarkers of long-term airborne Mn exposure. This was also confirmed by the significant positive correlations between scalp hair Mn and bioaccessible Mn in coarse and fine fractions, and between fingernails Mn and all PM fractions. This implies that people living closer to a ferromanganese alloy plant are exposed to higher levels of airborne metal(loid)s, mainly Mn, leading to higher levels of this metal in scalp hair and fingernails, which according to the literature, might affect some neurological outcomes. According to sex, significant differences were observed for Fe, Cu and Pb in whole blood, with higher concentrations of Fe and Pb in males, and higher levels of Cu in females; and for Mn, Cu, Zn, Cd and Pb in scalp hair, with higher concentrations in males for all metal(loid)s except Cu.
Asunto(s)
Cadmio , Oligoelementos , Humanos , Masculino , Femenino , Cadmio/análisis , Plomo/análisis , Oligoelementos/análisis , Material Particulado/análisis , Biomarcadores , Aleaciones/análisis , Monitoreo del AmbienteRESUMEN
The photo-degradation of the emerging contaminant antipyrine (AP) was studied and optimized in a novel photocatalytic spinning disc reactor (SDR). A heterogeneous process (UV/H2O2/TiO2) was used. TiO2 was immobilized on the surface of a glass disc using a sol-gel method. A factorial design of experiments followed by a Neural Networks fitting allowed the optimal conditions to be determined for treating 50 mg/L of AP. Under these conditions (pH = 4; [H2O2]0 = 1500 mg/L; disc speed = 500 rpm; flowrate = 25 mL/s), AP was completely degraded in 120 min and regeneration of the disc allowed 10 cycles with no loss in efficiency. The value of the apparent volumetric rate constant was found to be 6.9·10-4 s-1 with no apparent mass transfer limitation. Based on the main intermediates identified, a mechanism is proposed for antipyrine photodegradation: Firstly, cleavage of the NN bond of penta-heterocycle leads to the formation of two aromatic acids and N-phenylpropanamide. An attack to the CN bond in the latter compound produces benzenamine. Finally, the phenyl ring of the aromatic intermediates are opened and molecular organic acids are formed.
Asunto(s)
Antipirina/química , Titanio/química , Contaminantes Químicos del Agua/química , Purificación del Agua , Catálisis , Humanos , Fotólisis , Rayos Ultravioleta , Purificación del Agua/métodosRESUMEN
AIMS: To explore whether the transfer of very poor quality (VPQ) embryos is associated with an increase in congenital malformations or perinatal problems. METHODS: In this retrospective case-control study, 74 children conceived by in vitro fertilization (IVF) and/or intracytoplasmic sperm injection (ICSI) resulting exclusively from the transfer of VPQ embryos were compared with 1,507 children born after the transfer of top morphological quality (TQ) embryos over the same period of time in the same centers. RESULTS: The prevalence of birth defects in children resulting from VPQ embryos was 1.35% (1/74), similar to the 1.72% (26/1,507) when only TQ embryos were transferred; the rate of chromosomal abnormalities detected was also similar (0.0 vs. 0.4%), as was perinatal mortality. After correcting for multiplicity (higher in the TQ group), the aforementioned parameters remained similar in the two groups. CONCLUSION: Congenital malformations and perinatal complications do not seem to be more common in children born after transfer of VPQ embryos in IVF/ICSI cycles. Given our preliminary data, which need to be confirmed in much larger studies, when only VPQ embryos are available for transfer in IVF/ICSI cycles, we do not believe that they should be discarded with the intention of avoiding birth defects or perinatal complications.
Asunto(s)
Aberraciones Cromosómicas/embriología , Anomalías Congénitas/epidemiología , Transferencia de Embrión/estadística & datos numéricos , Fertilización In Vitro/estadística & datos numéricos , Complicaciones del Trabajo de Parto/epidemiología , Inyecciones de Esperma Intracitoplasmáticas/estadística & datos numéricos , Adulto , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Complicaciones del Trabajo de Parto/mortalidad , Embarazo , España/epidemiologíaRESUMEN
An alternative metric to account for particulate matter (PM) composition-based toxicity is the ability of PM-species to generate reactive oxygen species (ROS) and deplete antioxidants, the so-called oxidative potential (OP). Acellular OP assays are the most used worldwide, mainly those based on ascorbic acid (AA) and dithiothreitol (DTT) depletion; OP values are calculated from AA/DTT concentration over time kinetic curves. Since a great variability in OP-DTT and OP-AA values can be found in the literature, the understanding of those factors affecting the kinetic rate of AA and DTT oxidation in the presence of PM-bound species will improve the interpretation of OP values. In this work, a kinetic study of the oxidation rate of AA and DTT driven by species usually found in PM (transition metals and naphthoquinone (NQ)) was carried out. In particular, the influence of the concentration of Cu(II), Fe(II), Fe(III), Mn(II), Mn(III), and 1,4-NQ, and the type of fluid used in the assay (phosphate buffer (PB), phosphate buffer saline (PBS) and artificial lysosomal fluid (ALF)) is analysed and discussed. The reaction orders with respect to the AA/DTT and the active compound, and the kinetic rate constants were also determined. The results show great variability in OP values among the studied species depending on the fluid used; the OP values were mostly higher in PB0.05 M, followed by PBS1x and ALF. Moreover, different species concentration-responses for OP-DTT/OP-AA were obtained. These differences were explained by the different reaction orders and kinetic rate constants obtained for each active compound in each fluid.
Asunto(s)
Ácido Ascórbico , Cobre , Ditiotreitol , Hierro , Manganeso , Naftoquinonas , Oxidación-Reducción , Cinética , Ácido Ascórbico/química , Naftoquinonas/química , Ditiotreitol/química , Hierro/química , Cobre/química , Manganeso/química , Material Particulado/química , Material Particulado/análisis , Antioxidantes/química , Especies Reactivas de Oxígeno/metabolismo , Especies Reactivas de Oxígeno/químicaRESUMEN
PURPOSE: The aim of our study was to ascertain the influence of hCG levels at oocyte pick-up on IVF outcomes, and their relationship with clinical parameters. METHODS: A prospective study was performed including 473 women undergoing IVF, aged under 40 years. Blood samples to analyze hCG levels were obtained at the time of follicular aspiration, 36 h after the administration of 250 µg of recombinant hCG. RESULTS: Neither the numbers of oocytes obtained or fertilized, nor the pregnancy rate, were correlated with hCG levels. Moreover, hCG values were very similar in women who did and did not become pregnant (123.3 ± 48.7 and 117.5 ± 44.7 mUI/mL). Cases in which no oocytes were recovered after follicular aspiration had similar hCG levels to those in which more than 1 oocyte was obtained. On the other hand, hCG levels were negatively related to body mass index, weight, and age. CONCLUSIONS: These data indicate that after the administration of 250 µg of recombinant hCG, hCG levels are not responsible for failure to recover oocytes. Specifically, there was no correlation between plasma hCG levels and the number of oocytes obtained or other markers of IVF outcome. There was, however, an inverse relationship with BMI, body weight and age.
Asunto(s)
Gonadotropina Coriónica/sangre , Gonadotropina Coriónica/uso terapéutico , Fertilización In Vitro , Recuperación del Oocito , Proteínas Recombinantes/uso terapéutico , Adulto , Factores de Edad , Índice de Masa Corporal , Gonadotropina Coriónica/farmacología , Femenino , Humanos , Embarazo , Índice de Embarazo , Estudios Prospectivos , Proteínas Recombinantes/farmacología , Resultado del TratamientoRESUMEN
This single-centre, randomized, parallel group, comparative study aimed to identify potential benefits of mid-follicular recombinant human LH (r-HLH) supplementation in women aged 35-39 years undergoing ovarian stimulation for intracytoplasmic sperm injection (ICSI). The main endpoint was the number of metaphase II oocytes retrieved. After pituitary suppression with a gonadotrophin-releasing hormone agonist, ovarian stimulation was initiated with recombinant human FSH (r-HFSH; 300-450 IU/day). On stimulation day 6, patients were randomized to receive r-HFSH alone or r-HFSH + r-HLH (r-HLH 150 IU/day) for the remainder of the stimulation period. Final follicular maturation was triggered with 250 µg of recombinant human chorionic gonadotrophin. After assessing oocyte nuclear maturity, oocyte were fertilized by ICSI and afterwards embryo quality was analyzed. Of the 131 women enrolled, 68 were allocated to r-HFSH alone and 63 to r-HFSH + r-HLH. No significant differences were observed in markers of either oocyte or embryo quality or quantity. However, higher rates of implantation and live birth per started cycle were observed with r-HLH supplementation than with r-HFSH alone. Although additional large studies are required to further investigate these findings, r-HLH supplementation for women aged 35-39 years undergoing ICSI is recommended as it may have a beneficial action on implantation.
RESUMEN
Endocannabinoid anandamide and cannabinoid receptors have been described in some organs of the female reproductive system, but little is known about the expression of these receptors in human oocytes. The aim of the study was to describe the expression of cannabinoid receptors in human oocytes and to investigate their differential distribution at various stages of meiotic resumption in human oocytes. A total of 750 human oocytes from 214 patients were analysed by Western blot, immunocytochemistry and PCR. For this study, oocytes that were not suitable for intracytoplasmic sperm injection (ICSI) (germinal-vesicle and metaphase-I stages), as well as metaphase-II oocytes that had not developed into an embryo after ICSI were used. Western blot analysis revealed the presence of CB1 and CB2 receptor proteins in human oocytes. CB1 and CB2 receptor immunostaining patterns changed during the various stages of meiotic resumption. Localization of CB1 receptor was peripheral at germinal-vesicle stage, homogeneous over the entire oocyte at metaphase I and peripheral at mature metaphase II. CB2 receptor localization was peripheral at germinal-vesicle and metaphase-I stages but homogeneous over the entire cell at metaphase II. This finding suggests a possible role for endocannabinoids, acting via receptors, in the maturation of female gametes and fertilization. The number of couples with sterility problems attending fertility programmes is rising but treatment is not always successful. Important problems associated with failure to conceive remain unresolved because many physiological aspects of human reproduction are still unknown. Endocannabinoids are endogenous chemical compounds that mimic the action of the main psychoactive component of marijuana, delta-9-tetrahydrocannabinol. An endogenous cannabinoid named anandamide has been found in human follicular fluid. Thus, in order to develop knowledge in this field, in the present study we have described the presence of the cannabinoid receptors CB1 and CB2 (the proteins required to mediate the action of the cannabinoids) in the early stages of meiotic resumption of oocytes (the stages before ovulation) and we could postulate that the endocannabinoids could act in the regulation of maturation of oocytes. Our study, together with other studies, indicates that the endocannabinoid system may play a role in human reproduction.
Asunto(s)
Oocitos/metabolismo , Receptor Cannabinoide CB1/metabolismo , Receptor Cannabinoide CB2/metabolismo , Femenino , Fertilización , Humanos , Inmunohistoquímica , Meiosis , Metafase , Oocitos/crecimiento & desarrollo , ARN Mensajero/metabolismo , Receptor Cannabinoide CB1/análisis , Receptor Cannabinoide CB1/fisiología , Receptor Cannabinoide CB2/análisis , Receptor Cannabinoide CB2/fisiología , Reacción en Cadena de la Polimerasa de Transcriptasa InversaRESUMEN
The bioaccessibility of metal(loid)s in ambient particulate matter (PM) has been recently used to represent the risk of inhalation exposure. Nevertheless, different methodological factors affect the bioaccessibility values; among these, the type and composition of surrogate biological fluids and the liquid to solid ratio have been revealed to be the most important. To better understand how these methodological aspects affect the bioaccessibility, a reference material corresponding to urban dust (SRM1648a) was contacted with synthetic biological fluids commonly used in the literature representing surrogate fluids that may interact with fine (Gamble's solutions, artificial lysosomal fluid (ALF)) and coarse particles (gastric fluid), for liquid to solid (L/S) ratios ranging from 500 to 20,000. Visual MINTEQ 3.1. was used to enhance the discussion on how the solubility of metals in the leaching solution depends on the composition of the simulated fluids and the speciation of metals. The results obtained indicate that a small change in the composition of Gamble's solution (the presence of glycine) may increase significantly the bioaccessibility at a L/S ratio of 5,000. The highest bioaccessibility of most of the studied metal(loid)s at a L/S ratio of 5,000 was found for ALF fluid. The study of the effect of the L/S ratio showed that metal(loid)s bioaccessibility in Gamble's fluid increased logarithmically with increasing L/S ratio, while it remained practically constant in ALF and gastric fluid. This different behavior is explained assuming that the leaching of metal(loid)s in Gamble's solution is solubility-controlled, while in ALF and gastric fluid is availability-controlled.
Asunto(s)
Polvo , Oligoelementos , Exposición por Inhalación/análisis , Metales , Material ParticuladoRESUMEN
Water - the most vital resource, negatively affected by the linear pattern of growth - still tries to find its positioning within the emerging concept of circular economy. Fragmented, sectorial circularity approaches hide the risk of underestimating both the preservation of and impacts to water resources and natural capital. In this study, a game changing circularity assessment framework is developed (i.e. MSWCA). The MSWCA follows a multi-sectoral systems approach, symbiotically managing key water-related socio-economic (i.e. urban water, agro-food, energy, industry and waste handling) and non-economic (i.e. natural environment) sectors. The MSWCA modelling framework enables the investigation of the feedback loops between the nature-managed and human-managed systems to assess water and water-related resources circularity. The three CE principles lie at the core of the developed framework, enabling the consideration of physical, technical, environmental and economic aspects. An indicators database is further developed, including all the relevant data requirements, as well as existing and newly developed indicators assessing multi-sectoral systems' circularity. The MSWCA framework is conceptually applied to a fictional city, facilitating its understanding and practical use.
Asunto(s)
Ciclo Hidrológico , Agua , Ciudades , Ambiente , Humanos , Recursos HídricosRESUMEN
Age-related memory decline has been associated with changes in the medial prefrontal cortex (mPFC) function. In order to explore the role of mPFC in taste recognition memory, we have assessed mPFC c-Fos immunoreactivity in adult (5-month-old) and aged (24-month-old) male Wistar rats during the first (Novel), second (Familiar I), and sixth (Familiar II) exposure to a cider vinegar solution. Adult brains showed higher c-Fos expression in the ventral but not the dorsal region of mPFC during the second taste exposure. Interestingly, old brains exhibited an altered activity pattern selectively in the dorsal peduncular cortex (DP) which can be associated with a delayed attenuation of vinegar neophobia in this group. These results support the involvement of this area in the formation of safe taste memory. Further research is needed for understanding the role of DP in taste recognition memory and the impact of aging on it.
Asunto(s)
Habituación Psicofisiológica/fisiología , Corteza Prefrontal/metabolismo , Percepción del Gusto/fisiología , Factores de Edad , Envejecimiento , Animales , Trastorno de la Ingesta Alimentaria Evitativa/Restrictiva , Encéfalo/metabolismo , Encéfalo/fisiología , Corteza Cerebral/metabolismo , Masculino , Memoria , Corteza Prefrontal/fisiología , Ratas , Ratas Wistar , Reconocimiento en Psicología , GustoRESUMEN
This single-centre, randomized, parallel group, comparative study aimed to identify potential benefits of mid-follicular recombinant human LH (r-HLH) supplementation in women aged 35-39 years undergoing ovarian stimulation for intracytoplasmic sperm injection (ICSI). The main endpoint was the number of metaphase II oocytes retrieved. After pituitary suppression with a gonadotrophin-releasing hormone agonist, ovarian stimulation was initiated with recombinant human FSH (r-HFSH; 300-450 IU/day). On stimulation day 6, patients were randomized to receive r-HFSH alone or r-HFSH + r-HLH (r-HLH 150 IU/day) for the remainder of the stimulation period. Final follicular maturation was triggered with 250 mug of recombinant human chorionic gonadotrophin. After assessing oocyte nuclear maturity, oocyte were fertilized by ICSI and afterwards embryo quality was analyzed. Of the 131 women enrolled, 68 were allocated to r-HFSH alone and 63 to r-HFSH + r-HLH. No significant differences were observed in markers of either oocyte or embryo quality or quantity. However, higher rates of implantation and live birth per started cycle were observed with r-HLH supplementation than with r-HFSH alone. Although additional large studies are required to further investigate these findings, r-HLH supplementation for women aged 35-39 years undergoing ICSI is recommended as it may have a beneficial action on implantation.
Asunto(s)
Hormona Folículo Estimulante Humana/administración & dosificación , Hormona Luteinizante/administración & dosificación , Folículo Ovárico/fisiología , Inducción de la Ovulación/métodos , Adulto , Implantación del Embrión/efectos de los fármacos , Femenino , Fase Folicular , Humanos , Recuperación del Oocito/métodos , Folículo Ovárico/efectos de los fármacos , Embarazo , Resultado del Embarazo , Inyecciones de Esperma IntracitoplasmáticasRESUMEN
The intensification of the solar photo-Fenton system with ferrioxalate photoactive complexes and ultrasound applied to the mineralization of 15mg/L carbamazepine aqueous solution (CBZ) was evaluated. The experiments were carried out in a solar compound parabolic collector (CPC) pilot plant reactor coupled to an ultrasonic processor. The dynamic behavior of hydroxyl radicals generated under the different studied reaction systems was discussed. The initial concentrations of hydrogen peroxide and ferrous/oxalic acid and pH were found to be the most significant variables (32.79%, 25.98% and 26.04%, respectively). Under the selected optimal conditions ([H2O2]0=150mg/L; [Fe2+]0=2.5mg/L/[(COOH)2]0=12.1mg/L; pH=5) CBZ was fully degraded after 5min and 80% of TOC was removed using a solar photo-Fenton system intensified with ferrioxalate (SPFF). However, no improvement in the mineralization using SPFF process combined with ultrasound was observed. More mild pH conditions could be used in the SPFF system if compared to the traditional photo-Fenton (pH 3) acidic systems. Finally, a possible reaction pathway for the mineralization of CBZ by the SPFF system was proposed and therein discussed.
RESUMEN
The photo-Fenton degradation of carbamazepine (CBZ) assisted with ultrasound radiation (US/UV/H2O2/Fe) was tested in a lab thin film reactor allowing high TOC removals (89% in 35min). The synergism between the UV process and the sonolytic one was quantified as 55.2%. To test the applicability of this reactor for industrial purposes, the sono-photo-degradation of CBZ was also tested in a thin film pilot plant reactor and compared with a 28L UV-C conventional pilot plant and with a solar Collector Parabolic Compound (CPC). At a pilot plant scale, a US/UV/H2O2/Fe process reaching 60% of mineralization would cost 2.1 and 3.8/m3 for the conventional and thin film plant respectively. The use of ultrasound (US) produces an extra generation of hydroxyl radicals, thus increasing the mineralization rate. In the solar process, electric consumption accounts for a maximum of 33% of total costs. Thus, for a TOC removal of 80%, the cost of this treatment is about 1.36/m3. However, the efficiency of the solar installation decreases in cloudy days and cannot be used during night, so that a limited flow rate can be treated.
Asunto(s)
Carbamazepina/química , Carbamazepina/aislamiento & purificación , Costos y Análisis de Costo , Fotólisis , Ondas Ultrasónicas , Peróxido de Hidrógeno/química , Hierro/química , Proyectos Piloto , Rayos UltravioletaRESUMEN
The aim of this study was to examine the kinetics of the different mechanisms (radical pathway, photolysis, molecular reaction with H2O2 and reaction with ultrasonically generated oxidative species) involved in the homogeneous sono-photoFenton (US/UV/H2O2/Fe) mineralization of antipyrine present in a synthetic municipal wastewater effluent (ASMWE). The dynamic behavior of hydroxyl (HO) radical generation and consumption in mineralization reaction under different systems was investigated by measuring hydroxyl radical concentration during the reaction. The overall mineralization process was optimized using a Central-Composite Experimental Design (CCED) with four variables (initial concentrations of H2O2 and Fe(II), amplitude and pulse length). The response functions (pseudo-first order mineralization kinetic rate constants) were fitted using neural networks (NNs). Under the optimal conditions ([H2O2]o=500mgL-1, [Fe(II)]o=27mgL-1, Amplitude (%)=20andPulse length=1), the TOC removal was 79% in 50min. The radical reaction in the bulk solution was found be the primary mineralization pathway (94.8%), followed by photolysis (3.65%), direct reaction with H2O2 (0.86%), and reaction by ultrasonically generated oxidative species (0.64%). The role of the Fe catalyst on the radical reaction and the presence of refractory intermediates towards hydroxyl radical were also studied.
Asunto(s)
Antipirina/química , Ciudades , Peróxido de Hidrógeno/química , Radical Hidroxilo/química , Hierro/química , Minerales/química , Sonicación , Aguas Residuales/química , Catálisis , Procesos FotoquímicosRESUMEN
Complete mineralisation of reaction intermediates refractory towards hydroxyl radical, generated from a previous ineffective degradation of urban wastewater containing antipyrine by HO-mediated sono-photo-Fenton reaction, has been attained using persulfate anions simultaneously activated by heat energy (thermally, ultrasound) and UV-C light. The SO4(-)-based mineralisation process enables another reaction pathway generating more easy degradable derivatives. The influences of the initial concentration of persulfate, ultrasound amplitude, temperature and the reaction time in the previous HO-based previous oxidation on the mineralisation degree were studied by using a Central-Composite Experimental Design. Under optimal conditions ([S2O8(2-)]o=1200mgL(-1), temperature=50°C, amplitude=10%, pH 2.8, HO-based reaction time=25min) practically complete degradation was achieved in approximately 120min. The contribution of HO and SO4(-) radicals in this system was also evaluated. The presence of chloride ion in urban wastewater can benefit the oxidation of acetate by sulfate radical. Results demonstrated that this activated persulfate-based oxidation system is a potential alternative to degrade intermediate compounds, which are refractory against hydroxyl radicals, generated in Advanced Oxidation Processes used to treat wastewater containing emerging contaminants such as antipyrine.
RESUMEN
We evaluated the effects of clenbuterol HCl (0.8 micrograms/kg, of body weight, IV), a beta 2 agonist, on ventilation-perfusion matching and hemodynamic variables in anesthetized (by IV route), laterally recumbent horses. The multiple inert gas elimination technique was used to assess pulmonary gas exchange. Clenbuterol HCl induced a decrease in arterial oxygen tension (from 57.0 +/- 1.8 to 49.3 +/- 1.2 mm of Hg; mean +/- SEM) as a result of increased shunt fraction (from 6.6 +/- 2.1 to 14.4 +/- 3.1%) and ventilation to regions with high ventilation-perfusion ratios. In contrast, no changes in these variables were found in horses given sterile water. In horses given clenbuterol HCl, O2 consumption increased from 2.23 +/- 0.18 to 2.70 +/- 0.14 ml.min-1.kg-1, and respiratory exchange ratio decreased from 0.80 +/- 0.02 to 0.72 +/- 0.01. Respiratory exchange ratio and O2 consumption were not significantly modified in sterile water-treated (control) horses. Clenbuterol HCl administration was associated with increased cardiac index (from 57.4 +/- 4.0 to 84.2 +/- 6.3 ml.min-1.kg-1), decreased total peripheral vascular resistance (from 108.3 +/- 9.3 to 47.6 +/- 2.8 mm of Hg.s.kg.ml-1), and decreased pulmonary vascular resistance (from 31.3 +/- 3.8 to 13.6 +/- 0.7 mm of Hg.s.kg.ml-1). Our findings indicated that clenbuterol HCl may potentiate hypoxemia as a result of increased shunt fraction in horses anesthetized by the IV route, and caused changes in hemodynamic variables that were consistent with its ability to stimulate beta 2-adrenergic receptors.
Asunto(s)
Clenbuterol/farmacología , Hemodinámica/efectos de los fármacos , Caballos/fisiología , Pulmón/fisiología , Consumo de Oxígeno/efectos de los fármacos , Circulación Pulmonar/efectos de los fármacos , Anestesia General/veterinaria , Animales , Temperatura Corporal/efectos de los fármacos , Gasto Cardíaco/efectos de los fármacos , Frecuencia Cardíaca/efectos de los fármacos , Pulmón/efectos de los fármacos , Respiración/efectos de los fármacos , Resistencia Vascular/efectos de los fármacosRESUMEN
OBJECTIVES: 1) To present the postoperative morbidity of complete thyroidectomies and the results of their clinical management and costs obtained after surgery. 2) To compare the results obtained for the morbidity and costs in the complete thyroidectomy Process, after the management changes introduced by the Endocrine Surgical Unit (ESU). 3) To define whether these changes improve the Value (benefit/cost ratio) of the Process. MATERIAL AND METHODS: Prospective study of cohorts conducted on 529 complete thyroidectomies performed between 1998 and 2011. We present their clinical-pathological characteristics and we compare the clinical and management results obtained after surgery in 2 time periods: 1998-2006 without ESU (group 1, 205 patients) and 2007-2011 with ESU (group 2, 324 patients). The clinical results and the possible benefits are assessed by studying the morbimortality (recurrent lesions, hypocalcaemia [<8 mg/dl], suffocative haematomas and bleeding), and those of management, for the evaluation of the use of operating room time, the average stay and the total cost of the Process. The statistical comparison study was made using Student t test, for the comparison of means and the Chi(2) to compare percentages, accepting P<.05 as significant. RESULTS: The global percentage of transient recurrent dysfunctions (TRD) was 6%, and for definitive recurrent paralysis (DRP) it was 1.5%. Hypocalcaemia, at 24 hours was 54.6%, at one month 7%, at six months 6.2% and that of definitive hypoparathyroidism 1.3%. There were 2.8% of suffocative haematomas and 2% adverse effects. The mean surgical time was 98 minutes, and the average stay was 3.66 days. In the comparison of results of the groups, the ESU improved the TRD index by nearly 7 points (10.2 vs. 3.4%, P=.002), that of DRP by 1.5 (2.4 vs. 0.4%; P=.3) until reaching under 1%. The figures on bleeding at 24 hours (53 vs. 44 cc; P=.002) and 48 hours (23 to 17 cc; P<.001), the rate of haematomas by another 6 points (6.3 vs. 0.6%; P<.001), and that of hypocalcaemia at 24 hours (P=.01). The average stay also improved (4.79 vs. 2.94 days; P<.001), the use of operating room time (reduced by 20 minutes/operation; P<.001), the total cost of the Process, decreasing by more than 2,000/Process (P<.001), and produced a total savings for the hospital in the period of study of 665,820. CONCLUSIONS: 1) The global results (post-operative morbidity) of our total thyroidectomies are within the quality standards. 2) The surgical specialisation and the changes introduced by the ESU improved the clinical results (greater benefit) and those of management, cutting down the average stay and the operating room usage time and decreasing costs. 3) The change in management increased the Value of the Process.