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1.
J Therm Biol ; 76: 1-7, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30143283

RESUMEN

Feed intake (FI) level affects body heat production in thermo-neutral pigs; exposure of pigs to heat stress (HS) also increases body temperature (BT). However remains unclear whether the FI level affects the heat production of HS pigs. This study analyzed the effect of FI level on BT of 9 HS pigs (46.3 ±â€¯2.6 kg body weight) implanted with a thermometer set to register the BT at 5-min intervals into the ileum. Pigs were divided in two groups randomly allotted to two FI treatments: high FI (HFI, 1.20 kg/d), and low FI (LFI, 0.96 kg/d), according to a two-period crossover experimental design. Pigs were fed 3-times a day (0600, 1200, and 2200 h), same amount each time (400 g or 320 g). Ambient temperature (AT) ranged from 29.0 to 35.4 °C. The BT of both HFI and LFI pigs followed a similar pattern along a 24-h period, but the BT of HFI pigs was higher than that of LFI pigs (P < 0.05). Postprandial afternoon and evening BT was higher than that after the morning meal (P < 0.05). The postprandial BT increment differed between meal times and AT, but not between FI levels. The BT of HFI and LFI pigs increased up to 0.18 and 0.22 °C, 0.60 and 0.61 °C, and 0.24 and 0.35 °C after the morning, afternoon, and evening meal, respectively, compared with the preprandial BT (P < 0.05). Hence, the dissipation capacity of feeding-related body heat appears to depend on the thermal load of HS pigs before consuming their meals; presumably, the thermal load during 6-h before the morning meal (AT below 32 °C) was lower than before the evening meal (AT above 32 °C). In conclusion, FI level affects the postprandial BT of HS pigs and its magnitude is larger after the evening and afternoon meals. These data suggest that HS pigs may reduce the voluntary FI during the afternoon and evening hours.


Asunto(s)
Temperatura Corporal , Ingestión de Alimentos , Respuesta al Choque Térmico , Sus scrofa/fisiología , Alimentación Animal , Animales , Regulación de la Temperatura Corporal , Periodo Posprandial , Temperatura
2.
J Anim Physiol Anim Nutr (Berl) ; 102(2): e718-e725, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28990262

RESUMEN

Feed intake and diet composition appear to affect the body temperature of pigs. Two trials were conducted to analyse the effect of feed intake level and dietary protein content on the intestinal temperature (IT) of pigs housed under thermo neutral conditions. Ten pigs (64.1 ± 1.3 kg initial body weight) fitted with an ileal cannula were used. A thermometer set to register the IT at 5-min intervals was implanted into the ileum through the cannula. In both trials, the ambient temperature ranged from 19.1 to 21.6°C and the pigs were fed at 07:00 and 19:00 hr (same amount each time). In trial 1, the pigs were fed daily 1.2 or 1.8 kg of a wheat-soybean meal diet. The IT followed a similar pattern along a 24-hr period regardless the feed intake level. The IT rapidly increased up to 0.61 and 0.74°C after the morning meal and up to 0.53 and 0.47°C after the evening meal in pigs fed 1.2 and 1.8 kg/d respectively. The postprandial IT was higher in pigs fed 1.8 kg after each meal (p < .05). In trial 2, pigs were fed daily 1.8 kg of a low (11%) or a high (22%) crude protein diet. The IT followed a similar pattern along the 24-hr period regardless the dietary protein level. The postprandial IT did not differ between pigs fed the low protein or the high protein (p > .10). The IT rapidly increased up to 0.66 and 0.62°C after the morning meal in pigs fed the high- and low-protein diet (p < .05), but there was no change after the evening meal (p > .10). In conclusion, the feed intake level affected the IT of pigs housed under TN conditions, but the dietary protein content had no effect.


Asunto(s)
Temperatura Corporal/efectos de los fármacos , Proteínas en la Dieta/farmacología , Ingestión de Alimentos/fisiología , Porcinos/fisiología , Alimentación Animal , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Composición Corporal , Dieta/veterinaria , Digestión , Metabolismo Energético , Ambiente , Vivienda para Animales , Masculino
3.
Science ; 192(4243): 1007-8, 1976 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-944951

RESUMEN

alpha-Methylphenylalanine reduces the phenylalanine hydroxylase activity of rat liver by 75 percent. Daily injections of this substance (plus phenylalanine) into rats from the 3rd to 15th day of age had no obvious toxic effects, and maintained a plasma concentration of phenylalanine comparable to that of phenylketonuric subjects.


Asunto(s)
Modelos Animales de Enfermedad , Hígado/enzimología , Fenilalanina Hidroxilasa/antagonistas & inhibidores , Fenilalanina/análogos & derivados , Fenilcetonurias , Aminoácidos/sangre , Animales , Animales Recién Nacidos , Humanos , Fenilalanina/sangre , Fenilcetonurias/sangre , Fenilcetonurias/inducido químicamente , Ratas
4.
Arch Environ Contam Toxicol ; 56(4): 754-60, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19165410

RESUMEN

Numerous state and federal agencies are increasingly concerned with the rapid expansion of invasive, noxious weeds across the United States. Herbicides are frequently applied as weed control measures in forest and rangeland ecosystems that frequently overlap with critical habitats of threatened and endangered fish species. However, there is little published chronic toxicity data for herbicides and fish that can be used to assess ecological risk of herbicides in aquatic environments. We conducted 96-h flowthrough acute and 30-day chronic toxicity studies with swim-up larvae and juvenile rainbow trout (Onchorhyncus mykiss) exposed to the free acid form of 2,4-D. Juvenile rainbow trout were acutely sensitive to 2,4-D acid equivalent at 494 mg/L (95% confidence interval [CI] 334-668 mg/L; 96-h ALC(50)). Accelerated life-testing procedures, used to estimate chronic mortality from acute data, predicted that a 30-day exposure of juvenile rainbow trout to 2,4-D would result in 1% and 10% mortality at 260 and 343 mg/L, respectively. Swim-up larvae were chronically more sensitive than juveniles using growth as the measurement end point. The 30-day lowest observable effect concentration (LOEC) of 2,4-D on growth of swim-up larvae was 108 mg/L, whereas the 30-day no observable effect concentration (NOEC) was 54 mg/L. The 30-day maximum acceptable toxicant concentration (MATC) of 2,4-D for rainbow trout, determined as the geometric mean of the NOEC and the LOEC, was 76 mg/L. The acute:chronic ratio was 6.5 (i.e., 494/76). We observed no chronic effects on growth of juvenile rainbow trout at the highest concentration tested (108 mg/L). Worst-case aquatic exposures to 2,4-D (4 mg/L) occur when the herbicide is directly applied to aquatic ecosystems for aquatic weed control and resulted in a 30-day safety factor of 19 based on the MATC for growth (i.e., 76/4). Highest nontarget aquatic exposures to 2,4-D applied following terrestrial use is calculated at 0.136 mg/L and resulted in a 30-day safety factor of 559 (e.g., 76/0.163). Assessment of the exposure and response data presented herein indicates that use of 2,4-D acid for invasive weed control in aquatic and terrestrial habitats poses no substantial risk to growth or survival of rainbow trout or other salmonids, including the threatened bull trout (Salvelinus confluentus).


Asunto(s)
Ácido 2,4-Diclorofenoxiacético/toxicidad , Ecosistema , Ecotoxicología , Herbicidas/toxicidad , Oncorhynchus mykiss , Contaminantes Químicos del Agua/toxicidad , Animales , Monitoreo del Ambiente/métodos , Herbicidas/análisis , Estadios del Ciclo de Vida/efectos de los fármacos , Estadios del Ciclo de Vida/fisiología , Longevidad/efectos de los fármacos , Medición de Riesgo , Pruebas de Toxicidad , Contaminantes Químicos del Agua/análisis
5.
Arch Environ Contam Toxicol ; 57(4): 725-31, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19777152

RESUMEN

Clopyralid (3,6-dichloro-2-pyridinecarboxylic acid) is a pyridine herbicide frequently used to control invasive, noxious weeds in the northwestern United States. Clopyralid exhibits low acute toxicity to fish, including the rainbow trout (Oncorhynchus mykiss) and the threatened bull trout (Salvelinus confluentus). However, there are no published chronic toxicity data for clopyralid and fish that can be used in ecological risk assessments. We conducted 30-day chronic toxicity studies with juvenile rainbow trout exposed to the acid form of clopyralid. The 30-day maximum acceptable toxicant concentration (MATC) for growth, calculated as the geometric mean of the no observable effect concentration (68 mg/L) and the lowest observable effect concentration (136 mg/L), was 96 mg/L. No mortality was measured at the highest chronic concentration tested (273 mg/L). The acute:chronic ratio, calculated by dividing the previously published 96-h acutely lethal concentration (96-h ALC(50); 700 mg/L) by the MATC was 7.3. Toxicity values were compared to a four-tiered exposure assessment profile assuming an application rate of 1.12 kg/ha. The Tier 1 exposure estimation, based on direct overspray of a 2-m deep pond, was 0.055 mg/L. The Tier 2 maximum exposure estimate, based on the Generic Exposure Estimate Concentration model (GEENEC), was 0.057 mg/L. The Tier 3 maximum exposure estimate, based on previously published results of the Groundwater Loading Effects of Agricultural Management Systems model (GLEAMS), was 0.073 mg/L. The Tier 4 exposure estimate, based on published edge-of-field monitoring data, was estimated at 0.008 mg/L. Comparison of toxicity data to estimated environmental concentrations of clopyralid indicates that the safety factor for rainbow trout exposed to clopyralid at labeled use rates exceeds 1000. Therefore, the herbicide presents little to no risk to rainbow trout or other salmonids such as the threatened bull trout.


Asunto(s)
Ecología , Monitoreo del Ambiente/métodos , Oncorhynchus mykiss/crecimiento & desarrollo , Ácidos Picolínicos/toxicidad , Contaminantes Químicos del Agua/toxicidad , Animales , Tamaño Corporal , Relación Dosis-Respuesta a Droga , Agua Dulce/análisis , Nivel sin Efectos Adversos Observados , Medición de Riesgo , Factores de Tiempo , Pruebas de Toxicidad Aguda/métodos , Pruebas de Toxicidad Crónica/métodos
6.
Cir Pediatr ; 20(4): 215-9, 2007 Oct.
Artículo en Español | MEDLINE | ID: mdl-18351242

RESUMEN

INTRODUCTION: This study assesses long-term outcome of patients with neuropatic bladders who underwent a bladder augmentation before puberty. PATIENTS AND METHODS: A total of 21 patients with low compliant neuropathic bladders who did not respond satisfactory to clean intermittent catheterization and/or anticholinergic therapy underwent bladder augmentation (mean age 8.3 yr, range; 2.5-12). Eighteen patients (86%) had VUR and/or ureterohydronephrosis and 17 (81%) had DMSA renal scars. Renal function was normal in all cases except one. All patients were followed at regular intervals with serum electrolyte and creatinine determination, urinary tract imaging, urodynamic evaluation and 24-hour urine collection. In the 18 cases augmented with intestine, urine cytology, cystoscopy and biopsy were also performed. RESULTS: Mean follow-up was 11 yr (8-14.5) and mean age at the end of follow-up was 19 yr (13.3-26.8). Urodynamic studies showed a significant improvement in bladder compliance. Upper urinary tract dilatation disappeared in all patients, VUR in 13/15p (86%) and no new renal scarring occurred. Renal function was normal at the end of follow-up in 20. Only 1 patient had UTI and another had a bladder stone. All patients are dry and 2 of them do not need clean intermittent catheterization. Urine cytology and cystoscopy were normal and no malignat lessions have been found in the biopsy specimens. CONCLUSIONS: Bladder augmentation done pre-puberty preserves renal function and resolves VUR and/or hydronephrosis in most cases without reimplanting the ureters. Close lifelong follow-up, including a cystoscopy, improves the results and prevents complications.


Asunto(s)
Vejiga Urinaria Neurogénica/cirugía , Niño , Preescolar , Femenino , Estudios de Seguimiento , Humanos , Intestinos/trasplante , Masculino , Estudios Retrospectivos
7.
Acta Orthop Belg ; 71(5): 615-7, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16305090

RESUMEN

Approximately 2% to 15% of the patients with dislocated elbows are thought to present a fracture of the coronoid process of the ulna, but such a fracture does not often present in isolation. Its exact incidence is difficult to ascertain given the lack of studies on the subject. One case is presented of an isolated fracture of the coronoid process and it is placed in the context of the existing literature.


Asunto(s)
Lesiones de Codo , Fijación de Fractura , Fracturas del Cúbito/terapia , Accidentes por Caídas , Niño , Humanos , Masculino , Fracturas del Cúbito/patología
8.
Rev Esp Cir Ortop Traumatol ; 59(1): 14-8, 2015.
Artículo en Español | MEDLINE | ID: mdl-25440456

RESUMEN

OBJECTIVE: In uncemented revision total hip replacement due to polyethylene wear, the metal cup needs to be maintained when its stability is checked during surgery, only replacing the polyethylene that is cemented if anchoring is not possible. The aim of the present study was to evaluate the medium-term clinical and radiological results of a polyethylene liner cemented into an osseointegrated acetabular shell component. MATERIAL AND METHOD: A retrospective analysis was performed on 15 patients in whom the surgical indication was polyethylene wear, with a mean follow-up of 6.1 years (range 3.5-9.7 years). The Harris Hip Score was used to assess the clinical results before surgery and at the end of follow-up. Anteroposterior and axial X-rays of the hip were taken to rule out complications. RESULTS: The mean Harris Hip Score improved, increasing from 64.7 points before the surgery to 80.3 at the end of follow-up. The osteolytic lesions disappeared, or at least the size did not increase, in the follow-up X-rays. One patient (6.7%) suffered 2 dislocation episodes that were treated without the need for surgery. Another patient presented with aseptic loosening of the femoral stem that required a replacement. CONCLUSIONS: Cementing the polyethylene liner, when anchoring is not possible, in an uncemented osseointegrated metal shell is a technique that offers good results in the medium term, and which may minimise the complications that may occur with the replacement of the shell component, without compromising its stability.


Asunto(s)
Artroplastia de Reemplazo de Cadera/métodos , Cementos para Huesos , Prótesis de Cadera , Polietileno , Falla de Prótesis , Adulto , Anciano , Artroplastia de Reemplazo de Cadera/instrumentación , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Diseño de Prótesis , Reoperación , Estudios Retrospectivos
9.
Fertil Steril ; 39(3): 316-20, 1983 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-6219012

RESUMEN

Between the years 1974 and 1980, 13 patients underwent a conservative (salpingotomy) surgical procedure for tubal pregnancy in their only fallopian tube. In this group, one patient has been lost to follow-up, and one has intentionally avoided pregnancy, although tubal patency was documented by hysterosalpingogram. All the remaining patients have had at least one term pregnancy. The diagnosis was confirmed in all instances by laparoscopy prior to laparotomy. In 11 patients, the ectopic pregnancy was unruptured. One ectopic pregnancy had ruptured and one had resulted in a tubal abortion. All patients underwent essentially the same conservative procedure, performed by the same surgical team, with close adherence to the principles of microsurgery. This technique is described in detail. Since each of these patients had only one tube, this report reaffirms the value of conservative surgery for tubal pregnancy.


Asunto(s)
Trompas Uterinas/cirugía , Embarazo Tubario/cirugía , Embarazo , Adulto , Femenino , Humanos , Laparoscopía , Microcirugia/métodos , Embarazo Tubario/diagnóstico , Rotura Espontánea
10.
Fertil Steril ; 56(5): 1001-3, 1991 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-1936308

RESUMEN

Hysteroscopic resection of the uterine septum is currently the accepted technique for dealing with this congenital uterine abnormality. Its advantages over the transabdominal approach are: it can be performed on an outpatient basis, it requires minimal recovery time, and it does not commit the patient to a subsequent cesarean section. This communication reports on a new transcervical approach that does not require the use of a hysteroscope. Thirty-four patients have now undergone resection of uterine septae using this technique. The results have been consistently good, requiring a short operative time and minimal instrumentation. We have experienced no complications.


Asunto(s)
Enfermedades Uterinas/cirugía , Aborto Espontáneo/etiología , Cuello del Útero , Estudios de Evaluación como Asunto , Femenino , Humanos , Histerosalpingografía , Periodo Posoperatorio , Embarazo , Procedimientos Quirúrgicos Operativos/métodos , Enfermedades Uterinas/complicaciones , Enfermedades Uterinas/diagnóstico por imagen
11.
Acta Orthop Belg ; 66(3): 272-8, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11033918

RESUMEN

Nineteen cases of osteoarthritis of the knee with valgus deformity in 17 patients were treated by femoral supracondylar varus osteotomy (17 cases) or by high tibial varus osteotomy (2 cases) over the last 15 years. Fixation was performed using a 95 degrees AO blade-plate in 13 of the femoral osteotomies and a straight plate in the other four. The mean follow-up time was 6.5 years. The valgus deformity was idiopathic in 14 cases, secondary to rheumatoid arthritis in 2 cases and to tibial valgus in one case. The Hospital for Special Surgery (HSS) score was used to evaluate the clinical results: nearly 75% were excellent or good. The causes related to poor results are analyzed regarding indication and surgical technique. It appears that varus osteotomy is an effective procedure for the treatment of osteoarthritis of the knee with valgus deformity, above all in order to alleviate pain, although the operation requires precision, and correct selection of patients is of prime importance.


Asunto(s)
Rodilla/anomalías , Rodilla/cirugía , Osteoartritis de la Rodilla/cirugía , Osteotomía/métodos , Anciano , Femenino , Fémur/cirugía , Estudios de Seguimiento , Humanos , Deformidades Adquiridas de la Articulación/cirugía , Masculino , Persona de Mediana Edad , Osteoartritis de la Rodilla/complicaciones , Tibia/cirugía , Resultado del Tratamiento
12.
Rev Chir Orthop Reparatrice Appar Mot ; 86(8): 794-800, 2000 Dec.
Artículo en Francés | MEDLINE | ID: mdl-11148417

RESUMEN

PURPOSE OF THE STUDY: The aim of this work was to determine whether erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) and alpha-1-antitrypsin (A1AT) levels are correlated significantly with early postoperative infectious complications after hip prosthetic surgery. MATERIALS AND METHODS: This prospective study was conducted on 100 total hip replacements performed between 1994 and 1995. ESR, CRP and A1AT were obtained before surgery then at 1, 2 and 6 weeks after surgery. RESULTS: Seven bacteriologically proven cases of infection were reported. Infection was considered to be superficial if it did not extend deeper than the muscles fascia. There was a strong statistical correlation between A1AT level and infection for all postoperative times (p<0.0001). A1AT was highly sensitive (87.5 p. 100) and specific (85.8 p. 100) for infection compared with ESR (sensibility 70 p. 100 and specificity 65.9 p. 100) and CRP (sensitivity 63.6 p. 100 and specificity 80.1 p. 100). DISCUSSION AND CONCLUSION: In our hands, A1AT can be a most useful diagnostic tool for infection after prosthesis hip surgery. Although not totally specific, it is highly sensitive for infection compared with other tools such as ESR and CRP more frequently used. These findings suggest an avenue of research on the role of A1AT in infectious complications after prosthetic joint surgery.


Asunto(s)
Infecciones por Acinetobacter/diagnóstico , Pruebas Enzimáticas Clínicas , Prótesis de Cadera/efectos adversos , Infecciones Relacionadas con Prótesis/diagnóstico , Infecciones Estafilocócicas/diagnóstico , Staphylococcus epidermidis , alfa 1-Antitripsina/análisis , Infecciones por Acinetobacter/sangre , Infecciones por Acinetobacter/prevención & control , Adulto , Anciano , Anciano de 80 o más Años , Antibacterianos/administración & dosificación , Antibacterianos/uso terapéutico , Profilaxis Antibiótica , Sedimentación Sanguínea , Proteína C-Reactiva/análisis , Cefamandol/administración & dosificación , Cefamandol/uso terapéutico , Cefalosporinas/administración & dosificación , Cefalosporinas/uso terapéutico , Interpretación Estadística de Datos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Nefelometría y Turbidimetría , Cuidados Posoperatorios , Estudios Prospectivos , Infecciones Relacionadas con Prótesis/sangre , Infecciones Relacionadas con Prótesis/prevención & control , Sensibilidad y Especificidad , Infecciones Estafilocócicas/sangre , Infecciones Estafilocócicas/prevención & control , Factores de Tiempo , Tobramicina/administración & dosificación , Tobramicina/uso terapéutico , Vancomicina/administración & dosificación , Vancomicina/uso terapéutico
13.
Waste Manag ; 30(2): 268-73, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19793642

RESUMEN

The results of assays carried out on plates used in the construction industry, manufactured entirely with solid wastes of a recycled paper plant, are presented and compared with the results obtained using agglomerated wood and plywood plates. Previous results had shown that wastes are composed essentially of polymers when these wastes are generated by recycled paper produced with the "waved type II" shavings. These solid wastes were placed in a mold that was heated and pressed with a hydraulic press in order to obtain the plates. The waste-produced plates were submitted to tests for humidity, swelling, water absorption, density, modulus of rupture-static bending, modulus of elasticity and direct screw withdrawal. These same assays had been carried out on two types of commercial wood plates, agglomerated wood and plywood, in order to compare the results with those obtained with the waste plate. Waste plates had similar behavior to the agglomerated wood plate, but it was possible to distinguish greater flexibility in the waste-produced plate and a significant difference in the tests for swelling and water absorption which showed the waste plate had a better performance than the agglomerated wood and plywood plates.


Asunto(s)
Materiales de Construcción , Residuos Industriales , Conservación de los Recursos Naturales , Papel
14.
Acta Biomater ; 6(5): 1772-82, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-19913114

RESUMEN

Pure Mg has been proposed as a potential degradable biomaterial to avoid both the disadvantages of non-degradable internal fixation implants and the use of alloying elements that may be toxic. However, it shows excessively high corrosion rate and insufficient yield strength. The effects of reinforcing Mg by a powder metallurgy (PM) route and the application of biocompatible corrosion inhibitors (immersion in 0.1 and 1M KF solution treatments, 0.1M FST and 1M FST, respectively) were analyzed in order to improve Mg mechanical and corrosion resistance, respectively. Open circuit potential measurements, polarization techniques (PT), scanning electrochemical microscopy (SECM) and electrochemical impedance spectroscopy (EIS) were performed to evaluate its corrosion behavior. SECM showed that the local current of attacked areas decreased during the F(-) treatments. The corrosion inhibitory action of 0.1M FST and 1M FST in phosphate buffered solution was assessed by PT and EIS. Under the experimental conditions assayed, 0.1M FST revealed better performance. X-ray photoelectron spectroscopy, energy dispersive X-ray and X-ray diffraction analyses of Mg(PM) with 0.1M FST showed the presence of KMgF(3) crystals on the surface while a MgF(2) film was detected for 1M FST. After fluoride inhibition treatments, promising results were observed for Mg(PM) as degradable metallic biomaterial due to its higher yield strength and lower initial corrosion rate than untreated Mg, as well as a progressive loss of the protective characteristics of the F(-)-containing film which ensures the gradual degradation process.


Asunto(s)
Fluoruros/farmacología , Magnesio/química , Metalurgia/métodos , Tampones (Química) , Materiales Biocompatibles Revestidos/farmacología , Corrosión , Impedancia Eléctrica , Electricidad , Electrodos , Microscopía Electrónica de Rastreo , Espectroscopía de Fotoelectrones , Potenciometría , Polvos , Espectrometría por Rayos X , Propiedades de Superficie/efectos de los fármacos , Resistencia a la Tracción/efectos de los fármacos , Termodinámica , Difracción de Rayos X
15.
Acta Biomater ; 6(5): 1763-71, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-19446048

RESUMEN

The corrosion behaviour of AZ31 magnesium alloy with different grain sizes immersed in simulated body fluids was compared in chloride solution (8 gl(-1)) and in phosphate-buffer solution (PBS). The influence of immersion time was also analyzed. Electrochemical techniques such as open circuit potential, polarization curves, transient currents and electrochemical impedance spectroscopy, complemented with scanning electron microscopy and energy dispersive spectroscopy, were used. Immediately after the immersion in the corrosive media the corrosion resistance was similar for both grain sizes of the AZ31 alloy and higher in NaCl solutions than in PBS. However, this corrosion behaviour was reversed after longer periods of immersion due to the stabilizing of the corrosion products of MgO by P-containing compounds. These P-compounds contribute to a higher level of protection by hindering the aggressive action of chloride ions. The best corrosion behaviour of the AZ31 alloy was obtained for the finest grain alloy associated with the highest transfer resistance value, after long periods of immersion in PBS.


Asunto(s)
Aleaciones/química , Líquidos Corporales/química , Magnesio/química , Tamaño de la Partícula , Corrosión , Impedancia Eléctrica , Electricidad , Cinética , Potenciometría , Soluciones , Espectroscopía Infrarroja por Transformada de Fourier , Factores de Tiempo
16.
J Pediatr Urol ; 5(1): 30-3, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18774747

RESUMEN

OBJECTIVE: We assessed clinical and urodynamic outcomes, over a minimum 10-year follow-up period, of neuropathic bladder patients treated with a bladder augmentation (BA) to determine if periodic urodynamic studies are needed. MATERIAL AND METHODS: Thirty-two patients with poorly compliant bladders underwent BA at a mean age of 11 years (2.5-18). Mean follow-up was 12 years (10-14.5) and mean patient age at the end of the study was 22 years (12.2-33). During follow-up all patients were controlled at regular intervals with urinary tract imaging, serum electrolyte and creatinine levels, cystoscopy and urodynamic studies. Preoperative, 1-year post-BA and latest urodynamic studies results were compared. RESULTS: Urodynamic studies at 1-year post-BA showed a significant increase in bladder capacity and a decrease in end-filling detrusor pressure compared with preoperative values (396 vs 106 ml; 10 vs 50 cm H(2)O, P<0.0001). The increase in bladder capacity was more significant at the end of the study than after 1 year (507.8 vs 396 ml, P<0.002). Thirteen patients had phasic contractions after 1 year and 11 at the end (not significant, NS), and these contractions were more frequent with colon than with ileum (NS). At the end of follow-up, phasic contraction pressure had decreased while trigger volume had increased (35 vs 28 cm H(2)O; 247 vs 353 ml, NS). All patients are dry and have normal renal function, except one who had mild renal insufficiency before BA. CONCLUSION: BA improves bladder capacity and pressure, and these changes are maintained over time (although phasic contractions do not disappear). Repeated urodynamic studies are only necessary when upper urinary tract dilatation or incontinence does not improve.


Asunto(s)
Monitoreo Intraoperatorio/métodos , Vejiga Urinaria Neurogénica/fisiopatología , Urodinámica/fisiología , Procedimientos Quirúrgicos Urológicos/métodos , Niño , Preescolar , Femenino , Estudios de Seguimiento , Humanos , Masculino , Estudios Retrospectivos , Factores de Tiempo , Resultado del Tratamiento , Vejiga Urinaria Neurogénica/cirugía
17.
J Pediatr Urol ; 4(1): 27-31, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18631888

RESUMEN

OBJECTIVE: This study assesses clinical outcome, after at least 8 years, of augmentation done before or at puberty in neuropathic bladders. PATIENTS AND METHODS: A total of 29 children with neuropathic bladders who did not respond satisfactorily to clean intermittent catheterisation and anti-cholinergic therapy underwent enterocystoplasty at a mean age of 11.8 years (range 3-18). Twenty-one children (72.4%) had vesicoureteral reflux (VUR) and/or ureterohydronephrosis and 22 (75.8%) had dimercapto-succinic acid scars, but all had normal renal function. All patients were followed at regular intervals with urinary tract imaging, serum electrolytes, creatinine, urodynamic evaluation and 24-h urine collection. Urine cytology, cystoscopy and biopsy were performed at the end of follow-up. RESULTS: Mean follow-up was 11 years (range 8-14.5) and mean age at the end of follow-up was 22.2 years (range 13.2-31). Urodynamic studies showed a significant improvement in bladder compliance in all patients. Upper urinary tract dilatation disappeared in all, VUR in 13/17 (76.4%), and no new renal scarring occurred in any patient. At the end of follow-up, renal function was normal in all according to serum creatinine, but cystatin C levels were normal in 27 and elevated in two. Significant proteinuria and low concentrations of renin and aldosterone were present in 80% and 82%, respectively. Only one patient had urinary tract infection, three had bladder stones, and in another a catheterisable channel was made. All patients were dry with normal urine cytology and cystoscopy, and no malignant lesions have been found in the biopsy specimens. CONCLUSION: Enterocystoplasty has preserved renal function and resolved VUR and/or hydronephrosis in most patients. The future implications of proteinuria and the low serum levels of renin and aldosterone, as well as the best indicator for measuring renal function, have yet to be determined. Close, life-long follow-up, including cystoscopy, is necessary to prevent complications.


Asunto(s)
Vejiga Urinaria Neurogénica/cirugía , Vejiga Urinaria/cirugía , Adolescente , Aldosterona/sangre , Niño , Preescolar , Femenino , Humanos , Hidronefrosis/cirugía , Riñón/fisiopatología , Masculino , Meningomielocele/cirugía , Renina/sangre , Estudios Retrospectivos , Resultado del Tratamiento , Vejiga Urinaria Neurogénica/etiología , Vejiga Urinaria Neurogénica/fisiopatología , Urodinámica , Reflujo Vesicoureteral/cirugía
18.
Rev. esp. cir. ortop. traumatol. (Ed. impr.) ; 59(1): 14-8, ene.-feb. 2015. tab, ilus
Artículo en Español | IBECS (España) | ID: ibc-132373

RESUMEN

Objetivo. Ante una cirugía de revisión de artroplastia total de cadera no cementada por desgaste de polietileno está indicado mantener el cotilo metálico cuando se compruebe intraoperatoriamente su estabilidad, sustituyendo únicamente el polietileno que se cementa si el anclaje no es posible. El objetivo del presente estudio fue evaluar los resultados clínicos y radiográficos a medio plazo de la cementación de polietileno dentro de un componente acetabular metálico osteointegrado. Material y método. Se analizaron retrospectivamente 15 pacientes cuya indicación para la cirugía fue el desgaste de polietileno, con un periodo de seguimiento medio de 6,1 años (rango 3,5-9,7 años). El Harris Hip Score se utilizó para valorar los resultados clínicos antes de la intervención y al final del seguimiento. Se realizaron radiografías anteroposteriores y axiales de cadera para descartar complicaciones. Resultados. La puntuación media en el Harris Hip Score mejoró, pasando de los 64,7 puntos en el preoperatorio a los 80,3 al final del seguimiento. Las lesiones osteolíticas desaparecieron, o al menos no aumentaron de tamaño, en los controles radiográficos. Una paciente (6,7%) sufrió 2 episodios de luxación, que se trataron sin necesidad de cirugía. Otro paciente presentó aflojamiento aséptico del vástago femoral, que requirió el recambio. Conclusiones. La cementación del polietileno, cuando no sea posible su anclaje, en un cotilo metálico no cementado osteointegrado es una técnica que ofrece buenos resultados a medio plazo, y que minimiza las complicaciones que conlleva el recambio del componente acetabular, sin comprometer su estabilidad (AU)


Objective. In uncemented revision total hip replacement due to polyethylene wear, the metal cup needs to be maintained when its stability is checked during surgery, only replacing the polyethylene that is cemented if anchoring is not possible. The aim of the present study was to evaluate the medium-term clinical and radiological results of a polyethylene liner cemented into an osseointegrated acetabular shell component. Material and method. A retrospective analysis was performed on 15 patients in whom the surgical indication was polyethylene wear, with a mean follow-up of 6.1 years (range 3.5-9.7 years). The Harris Hip Score was used to assess the clinical results before surgery and at the end of follow-up. Anteroposterior and axial X-rays of the hip were taken to rule out complications. Results. The mean Harris Hip Score improved, increasing from 64.7points before the surgery to 80.3 at the end of follow-up. The osteolytic lesions disappeared, or at least the size did not increase, in the follow-up X-rays. One patient (6.7%) suffered 2 dislocation episodes that were treated without the need for surgery. Another patient presented with aseptic loosening of the femoral stem that required a replacement. Conclusions. Cementing the polyethylene liner, when anchoring is not possible, in an uncemented osseointegrated metal shell is a technique that offers good results in the medium term, and which may minimise the complications that may occur with the replacement of the shell component, without compromising its stability (AU)


Asunto(s)
Humanos , Masculino , Femenino , Persona de Mediana Edad , Artroplastia de Reemplazo de Cadera/métodos , Artroplastia de Reemplazo de Cadera/tendencias , Artroplastia de Reemplazo de Cadera , Polietileno/uso terapéutico , Cementación/instrumentación , Cementación/métodos , Cementación , Cementación/normas , Cementación/tendencias , Estudios Retrospectivos , Osteólisis/diagnóstico , Osteólisis/cirugía , Osteólisis
19.
Rev Esp Fisiol ; 38 Suppl: 207-10, 1982.
Artículo en Español | MEDLINE | ID: mdl-7146578

RESUMEN

The establishment of a fibroblast bank from patients with biochemical alterations in the metabolism of aminoacids and organic acids has been initiated. The patients suffered from distinct variants of maple syrup urine disease, propionic acidaemia, methylmalonic acidaemia, lactic acidosis and hyperglycinuria. Thirty six human cell lines corresponding to patients with these diseases, their relatives and control individuals have been accumulated.


Asunto(s)
Errores Innatos del Metabolismo de los Aminoácidos/patología , Línea Celular , Fibroblastos , Errores Innatos del Metabolismo/patología , Acidosis/patología , Células Cultivadas , Niño , Preescolar , Fibroblastos/enzimología , Glicina/metabolismo , Humanos , Lactante , Recién Nacido , Lactatos/metabolismo , Enfermedad de la Orina de Jarabe de Arce/patología , Ácido Metilmalónico/metabolismo , Propionatos/sangre
20.
An Esp Pediatr ; 16(5): 416-20, 1982 May.
Artículo en Español | MEDLINE | ID: mdl-7114619

RESUMEN

The clinical and biochemical findings in a patient with the inherited disease so called hyperammonemia type II are presented. The patient was a male who had the first abnormal symptoms of tremors and continuous crying at 35 hours of age and exhibited a rapid clinical course dying 62 hours after birth. Rejection of food, respiratory problems, hypotonia and tonic-clonic convulsions were other outstanding clinical symptoms observed. Withdrawal of the feedings and initiation of a perfusion did not improve the clinical picture. Biochemical studies in samples of blood, urine and CSF revealed the presence of high concentrations of ammonia, alanine, glutamine and orotic acid. Final diagnosis was achieved when post mortem liver ornithine transcarbamylase activity was found to be lower than 6% with respect to that of adequate controls. Carbamyl phosphate synthetase, another urea cycle enzyme measured, was within normal limits of activity.


Asunto(s)
Errores Innatos del Metabolismo de los Aminoácidos/sangre , Amoníaco/sangre , Enfermedad por Deficiencia de Ornitina Carbamoiltransferasa , Errores Innatos del Metabolismo de los Aminoácidos/diagnóstico , Errores Innatos del Metabolismo de los Aminoácidos/enzimología , Animales , Humanos , Lactante , Hígado/enzimología , Masculino , Ratas , Urea/metabolismo
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