Effects of continuous chelation on the instrumentation of curved canals with a martensitic NiTi file system: an ex vivo micro-CT evaluation.

This study aimed to evaluate the influence of continuous chelation on apical transportation and centrality in shaped curved canals prepared with a martensitic file system and evaluated by micro-CT. Twenty-four lower molar canals with a curvature of 25º-40º were scanned pre-operatively with micro-CT and divided into 2 groups according to two different irrigation regimens (n = 12). Group 1 was irrigated with NaOCl, group 2 with Dual Rinse. All canals were prepared with VDW.ROTATE system. The samples were scanned post-operatively and evaluated at 1, 3 and 5 mm from the apex to determine apical transportation and canal centrality using VG Studio software. Statistical analysis was performed with SPSS software using the non-parametric Mann-Whitney test. No statistically significant differences were found between the two groups for both apical transportation and canal centrality at any of the levels studied (p < 05). The use of continuous chelation during the instrumentation of the canals with martensitic alloy files does not produce greater transportation and does not generate changes in centralization compared to NaOCl-only irrigation. Combined chelation and disinfection while shaping with martensitic NiTi can simplify the irrigation regimen without inducing iatrogenic aberrations.

La anestesia local con sedación como técnica de primera elección en la cirugía de hernia inguinal en régimen ambulatorio: rápida recuperación postoperatoria, alta seguridad y optimización de recursos / Local anesthesia with sedation as elective procedure in day ucise groin hernioplasty: quick postoperative recovery, high security and saving resources

Introducción: La anestesia local con sedación (ALS) se considera la técnica ‘gold estándar’ en la hernioplastia inguinal unilateral abierta, a pesar de que la anestesia raquídea (AR) sigue siendo la técnica más empleada en la práctica clínica diaria. La ALS parece aportar importantes ventajas con respecto a la AR, especialmente en el ámbito de la cirugía sin ingreso (CSI). El objetivo de este trabajo es demostrar los beneficios de ALS frente a AR en la hernioplastia inguinal en cuanto a los tiempos postoperatorios y las complicaciones postoperatorias en una unidad quirúrgica que realiza el 100 % de su actividad en régimen de Cirugía Mayor Ambulatoria (CMA). Material y método: 25 pacientes sometidos a hernioplastia inguinal con ALS y 25 con AR fueron incluidos en un estudio observacional retrospectivo comparativo. El estado clínico (ASA), el tipo de anestesia, los tiempos de recuperación en la Unidad de Recuperación Postanestésica (URPA), en la Unidad de Readaptación al Medio (URM) y durante su convalecencia en domicilio fueron comparados. Se registró cualquier complicación detectada en el periodo postoperatorio hasta el alta definitiva en ambos grupos. Resultados: Todos los pacientes fueron intervenidos según lo previsto. El tiempo de estancia media en URPA y URM, así como el tiempo transcurrido para recuperar la actividad normal tras la intervención, fueron significativamente inferiores en el grupo ALS. Las complicaciones fueron menos frecuentes y menos severas en el grupo ALS. Conclusión: Este trabajo afianza la ALS como técnica más adecuada que la AR para la intervención de hernia inguinal unilateral abierta en régimen de CMA (AU)

Introduction: Local anesthesia with sedation (LAS) is the ‘gold standar’ anesthetic technique in open groin hernioplasty, even if raquidea anesthesia (RA) is actually the most frequent anesthesia technique at the moment. LAS could contribute several advantages in this procedure especially in day case surgery. The main goal of this report is to show the benefits of LAS for groin hernioplasty regarding postoperative recovery times and outcomes in an only outpatient surgery unit. Material and methods: A 25 LAS group and a 25 RA group were enrolled in this observational retrospective comparative study. The clinical status (ASA), anesthetic technique, the Postanesthetic recovery Unit (PARU) recovery time, time before discharge, and time required to normal activity were compared. Any postoperative outcome was recorded. Results: All patients were operated as planned. Recovery times were shorter in the LAS group. Outcomes were more infrequent as well less severe in the LAS group. Conclusion: This report demonstrates that LAS is the most suitable anesthetic technique for unilateral open groin herniorraphy in Day case (AU)

Effect of sonic and ultrasonic activation on organic tissue dissolution from simulated grooves in root canals using sodium hypochlorite and EDTA.

AIM: To compare soft-tissue dissolution by sodium hypochlorite, with an EDTA intermediate rinse, with or without activation with passive ultrasonic activation (PUI) or sonic activation using the Endoactivator (EA) or Eddy tips (ED). METHODOLOGY: The root canals of eighty-three human maxillary central incisors were chemo-mechanically prepared and the teeth split. A standardized longitudinal intracanal groove was created in one of the root halves. Eighty-three porcine palatal mucosa samples were collected, adapted to fit into the grooves and weighed. The re-assembled specimens were randomly divided into four experimental groups (n = 20), based on the final rinse: no activation; EA; PUI; ED, using 2.5% sodium hypochlorite, with an EDTA intermediate rinse. A control group (n = 3) was irrigated with distilled water without activation. The solutions were delivered using a syringe and needle 2 mm from working length. Total irrigation time was 150 s, including 60 s of activation in the specific groups. The study was carried out at 36 ± 2 °C. The porcine palatal mucosa samples were weighed after completion of the assays. Student paired t-test and anova were used to assess the intra- and intergroup weight changes. The multiple comparisons were evaluated using Bonferroni correction (α = 0.05). RESULTS: Weight loss occurred in all experimental groups. Irrigant activation resulted in greater weight loss when compared to the nonactivated group [vs. EA (P = 0.001); vs. PUI (P < 0.001); vs. ED (P < 0.001)]. No significant differences were found amongst the different activation systems. CONCLUSIONS: Activation increased the tissue-dissolving activity of irrigants from artificial grooves in root canals of maxillary central incisors.

Resultados perinatales en fetos con flujo umbilical diastólico ausente / Perinatal outcome in fetuses with absent end diastolic umbilical flow

Objetivo: Estudiar los resultados perinatales de fetos diagnosticados con flujo umbilical ausente en diástole en el Hospital Universitario de Canarias, España. Métodos: Estudio retrospectivo de gestantes con Doppler fetal umbilical con flujo diastólico ausente entre 2004 y 2011, excluyendo embarazos gemelares. Las variables estudiadas fueron: edad y enfermedades maternas, edad gestacional al diagnóstico y parto, vía de parto, Apgar y estado del recién nacido. Resultados: Se recogieron 57 casos. Hubo un 43 por ciento de gestantes hipertensas y 19 por ciento de diabéticas. La edad gestacional media al diagnóstico fue de 30+4 semanas. En el 89% de los casos se observó redistribución del flujo y en el 21 por ciento el Doppler umbilical fue reverso. El 28 por ciento se acompañó de oligoamnios y en el 26 por ciento el peso fetal estimado inferior al percentil 3. Hubo 3 muertes fetales. En el 80 por ciento de los casos la vía de parto fue por cesárea. La supervivencia fue del 83 por ciento con una tasa de mortalidad perinatal del 17 por ciento. En el seguimiento entre 1 y 6 años encontramos un 35 por ciento de niños sin secuelas. Conclusiones: En nuestra serie, el Doppler con flujo umbilical ausente en diástole se relaciona con alto riesgo de morbimortalidad perinatal. El 65 por ciento de los niños tendrán secuelas de algún tipo en el seguimiento entre 1 a 6 años. El momento óptimo para la extracción fetal debe ser individualizado y resuelto junto con el consejo pediátrico y participación de los padres.

Objective: To determine the perinatal outcome in fetal growth restriction were umbilical artery Doppler end diastolic flow was absent. Methods: A retrospective study performed at the Canary Islands University Hospital. All consecutive cases between 2004 and 2011 were included. We excluded twin pregnancies. Data was abstracted for maternal age, gestational age at diagnosis and delivery, mode of delivery, Apgar and perinatal adverse outcomes. Results: Fifty seven patients were included. Forty three percent had a pregnancy complicated by hypertension and 19 percent diabetes. Mean gestational age at diagnosis was 30+4 weeks. We found 89 percent and 21 percent absent umbilical artery end diastolic flow and reverse flow respectively. Oligohydramnios was seen in 28 percent of the cases. Fetal weight was below the third percentile in 26 percent of the cases. Fetal demise occurred in 3 cases. Mode of delivery was cesarean section in 80 percent of the cases. We found a rate of 17 percent perinatal mortality. At 1 to 6 years follow up 35 percent of the children had no sequelae. Conclusion: Absent end diastolic umbilical flow is associated with a high risk of perinatal mortality. Up to 65 percent of the children will show some type of sequelae. The optimal gestational date for fetal extraction should be individualized after multidisciplinary counseling.

The effect of different taper preparations on the ability of sonic and passive ultrasonic irrigation to reach the working length in curved canals.

AIM: To evaluate the penetration of irrigants up to working length using two different activation systems in curved canals instrumented with 0.04 and 0.08 taper instruments. METHODOLOGY: Sixty-eight mesiobuccal canals from mandibular first molars with curvatures between 30° and 40° were used. The samples were divided into group 1, canals instrumented to size 30, 0.04 taper, and group 2, instrumented to size 30, 0.08 taper. Both groups were irrigated with a contrast solution and divided in 2 subgroups of 15 samples each: Groups 1A and 2A were activated with passive ultrasonic irrigation (PUI), whilst groups 1B and 2B were activated with sonic irrigation (SI). Radiographs were taken to evaluate the penetration of the contrast solution up to working length. This evaluation was performed using Adobe Photoshop CS5. Results were analysed with the chi-square test and a logistic regression model. RESULTS: Only groups with 0.04 taper demonstrated significant differences where the activation with PUI was superior at reaching working length than SI (P = 0.010). The logistic regression model showed that the only correlation in reaching working length was the activation system used (P = 0.005). CONCLUSION: The results suggest that variation of canal taper does not affect the ability of PUI to reach the working length in curved canals whilst SI obtained inferior results with 0.04 taper canal preparations.

Efficacy of irrigation systems on penetration of sodium hypochlorite to working length and to simulated uninstrumented areas in oval shaped root canals.

AIM: To assess the ability of sodium hypochlorite (NaOCl) to penetrate simulated lateral canals and to reach working length (WL) when using the self-adjusting file (SAF). METHODOLOGY: Seventy single-rooted teeth with oval-shaped canals were used. Upon access, presence of a single canal was confirmed by direct visualization under a dental-operating microscope. Canal length and patency were obtained using a size 10 K-file and root length standardized to 18 mm. Pre-enlargement was restricted to the coronal one-third. The apical size of each canal was gauged at WL and samples larger than size 30 were excluded. Canals were instrumented for 5 min using the SAF system while delivering a total of 20 mL of 5.25% NaOCl and 5 mL of 17% EDTA. Then, the apical diameters were standardized to size 35 using hand files. Four hundred and twenty simulated lateral canals were then created during the clearing process and roots coated with wax to create a closed system. All samples were then cleared and randomly assigned to four experimental groups: 1 (n = 15) positive pressure; 2 (n = 15) SAF without pecking motion; 3 (n = 15) SAF with pecking motion; 4 (n = 15) apical negative pressure (ANP) irrigation and (n = 10) control groups. Samples were scored on the basis of the ability of the contrast solution to reach WL and permeate into the simulated lateral canals to at least 50% of the total length. The Kruskal-Wallis test was used to analyse irrigant penetration and the Tukey test to determine statistical differences between groups (P < 0.05). RESULTS: All samples irrigated with ANP were associated with irrigant penetration to WL (Table 1). The differences between group 4 (ANP) and all other groups were significant in penetration to WL (P < 0.05). The pecking motion allowed for further penetration of the irrigant when using the SAF system but failed to irrigate at WL. None of the experimental groups demonstrated predictable irrigation of simulated lateral canals. CONCLUSIONS: In this laboratory model, ANP was the only delivery system capable of irrigating consistently to full WL. None of the systems tested produced complete irrigation in artificial lateral canals.

Alternativas para la descarga de la úlcera neuropática en el pie diabético / Alternatives for pressure relief of neuropathic ulcer in the diabetic foot

Dentro de las complicaciones crónicas asociadas a la diabetes mellitus encontramoslas úlceras localizadas en el pie, que llegan a padecer el 15% de lospacientes alguna vez en el curso de su enfermedad y que a menudo derivan enuna amputación. La etiología de estas úlceras está normalmente asociada a lapresencia de una neuropatía diabética y una peor respuesta al estrés mecánico,que provoca altas presiones plantares. El uso de descargas como tratamientoetiológico es una parte integral del proceso de curación, ya que produce modificaciones en la histología de la úlcera, que pasa de un estado infl amatorio crónicoa una condición mucho más evolutiva. Existen múltiples estrategias para lareducción de la presión plantar que deben utilizarse de manera protocolizadapara poder conseguir resultados favorables. Este artículo presenta diferentesmétodos de reducción de la presión, de manera que el profesional reconozca laimportancia de su uso en la gestión de las úlceras del pie diabético(AU)

Among the chronic complications associated with diabetes mellitus, foot ulcersare present in 15% of patients sometimes in the course of their disease, andoften leads to amputation. These ulcers are usually neuropatic and have a poorresponse to mechanical stress that causes high plantar pressures. Using offloadingis an integral part of the healing process, which causes favorable histologicchanges in the ulcer, from a chronic inflammatory state to a better evolutionarycondition. There are many strategies for reducing plantar pressurewhich have to be used in a protocol manner to obtain favorable results. Thisarticle presents different methods of pressure reduction underling the importancefor professionals of their use in the management of diabetic foot ulcers(AU)

[Anosmia due to fibrous dysplasia]. / Anosmia debida a displasia fibrosa.

INTRODUCTION: Organic acidurias are a group of hereditary metabolic disorders characterized by an increase in excretion of organic acids in urine. L-2 hydroxyglutaric aciduria is a neurodegenerative disorder with insidious onset after infancy, which is likely inherited in an autosomal recessive mode, characterized by mental retardation, progressive ataxia, epilepsy, macrocephaly, pyramidalism and extrapyramidal symptoms in variable combinations,with subcortical encephalopathy and cerebral atrophy in neuroimaging studies. Biochemical diagnosis was based on the detection of high levels of L-2 hydroxyglutaric acid in body fluids. CLINICAL CASE: We present the case of a 42 year old male patient with psychomotor development delay, generalized tonic epileptic crisis, and ataxia and pyramidal syndrome after the age of 18 months. Neuroimaging study findings revealed subcortical leukoencephalopathy. Diagnosis of the disease was reached after measuring the level of L-2 hydroxyglutaric acid in body fluid (blood, urine and cerebrospinal fluid). This diagnosis was also confirmed in three of the patient's brothers who were affected by a non-filial neurological disease by measurement of this acid level in urine. The genetic study was performed in all the cases. DISCUSSION: As with the majority of patients who reach adulthood without having been diagnosed of this disease during infancy, we believe that this disorder should be considered as a possibility in adults presenting a combination of the symptoms described and subcortical encephalopathy in magnetic resonance imaging, regardless of whether there is a family background of it. Thus, it should be included in the differential diagnosis of leukodystrophy in adult patients.

Neurophysiological monitoring of lumbosacral spinal roots during spinal surgery: continuous intraoperative electromyography (EMG).

INTRODUCTION: Neurophysiological monitoring during spinal surgery reduces the associated neurological complications. Continuous EMG recording has developed an useful technique for spinal root monitoring PATIENTS AND METHODS: Fifty four patients who underwent surgery for several lumbosacral spinal lesions (low and high degree spondylolisthesis, spinal stenosis, degenerated or herniated lumbar discs) were studied to evaluate the effectiveness of continuous EMG recording in monitoring spinal root function during surgery. Electrical root or screw stimulation was also performed in nine of them. To correlate surgical spinal root lesion with a precise EMG injury activity an animal study with 5 pigs was performed; lesion was produced by prolonged spinal root traction. RESULTS: In the porcine group EMG discharges lasting longer than one minute after cessation of root traction was noted in 74% of spinal root levels (neurotonic discharges or pseudo-rhythmic activity in 70% of the cases). Spinal root lesion was demonstrated through EMG three weeks after surgery. In the patient group pathological-significant EMG activity was not recorded in any case during monitoring. Mechanical or chemical root stimulation during surgery produced brief lasting EMG bursts of no pathological significance. Only a patient developed a mild acute L5-S1 radiculopathy after surgery (1 false negative) and post-operative deficit was not observed in the rest. Electrical stimulation of spinal roots and screws allowed to identify root level and prove the adequate placement of screws. CONCLUSION: Spontaneous and evoked EMG recordings are simple techniques that provide continuous information about lumbosacral spinal roots function throughout surgery.

Síndrome de temblor y ataxia asociados a premutación X-frágil (FXTAS) / Tremor/ataxia fragile X associated syndrome (FXTAS)

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Effect of dietary grape pomace and vitamin E on growth performance, nutrient digestibility, and susceptibility to meat lipid oxidation in chickens.

Grape pomace (GP) is a source of polyphenols with powerful antioxidant capacity. An experiment was conducted to investigate the effect of inclusion of GP at levels of 5, 15, and 30 g/kg and alpha-tocopheryl acetate (200 mg/kg) in a corn-soybean basal diet on growth performance, protein and amino acid digestibilities; antioxidant activity of diet, serum and excreta, lipid oxidation of breast and thigh meats during refrigerated storage, and liver vitamin E concentration. Growth performance and protein and amino acid digestibilities were not affected among the different treatments. Total intake and digestibility of extractable polyphenols in the birds fed the GP diet were increased compared with birds fed supplemented and unsupplemented vitamin E diets. Antioxidant activity in vitamin E and GP diets and excreta exhibited higher scavenging free radical capacity than the control diet using 3-ethylbenzthiazoline-6-sulfonic acid and ferric reducing antioxidant power methods. Lipid oxidation (malondialdehyde concentration) in breast and thigh meats was lower in the birds fed the supplemented vitamin E diet than the control diet after 1, 4, and 7 d of refrigerated storage. Results showed a linear reduction of lipid oxidation in breast and thigh meats at 4 and 7 d with increasing content of GP in the diet. Oxidative stability in breast and thigh meats at 1, 4, and 7 d of storage was equivalent or less effective in GP diets compared with the vitamin E diet. A linear increase was observed in liver alpha-tocopherol concentration with increasing content of GP in the diet, but it was inferior to the supplemented vitamin E diet. In conclusion, the results showed that a dietary inclusion rate up to 30 g/kg of GP did not impair chickens growth performance and protein and amino acids digestibilities and increased antioxidant activity in diet and excreta. Grape pomace and vitamin E diets reduced the lipid oxidation of meat during refrigerated storage and increased liver alpha-tocopherol concentration, although these effects were greater, in some cases, by adding vitamin E to the diet.

In vitro activity of linezolid in combination with doxycycline, fosfomycin, levofloxacin, rifampicin and vancomycin against methicillin-susceptible Staphylococcus aureus.

The objective of this paper was to investigate the in vitro effects of linezolid combined with five antistaphylococcal antibiotics--doxycycline, fosfomycin, levofloxacin, rifampicin and vancomycin--upon methicillin-susceptible Staphylococcus aureus (MSSA). Five MSSA isolates from clinical specimens of human infections--hf008, hf095, hf295, hf602 and hf946--were used in this study. The checkerboard method was used to assess synergism between linezolid and the five antibiotics, and time-kill curves were carried out with the most active combinations. Indifference was the most common result achieved by the checkerboard method when linezolid was combined with rifampicin, vancomycin or doxycycline. The combination with levofloxacin yielded antagonism for two of the five isolates. However, four isolates showed synergy for the combination of linezolid plus fosfomycin with a fractional inhibitory concentration index (FICI) > or = 0.5. Neither linezolid nor fosfomycin alone inhibited growth at 1/4x minimum inhibitory concentration (MIC); but the combination of both drugs at 1/4 the respective MIC showed a synergistic bacteriostatic effect, a 2-3 log(10) decrease with respect to the most active antibiotic alone. In summary, the combination of subinhibitory.

In vitro activity of linezolid in combination with doxycycline, fosfomycin, levofloxacin, rifampicin and vancomycin against methicillin-susceptible Staphylococcus aureus

El objetivo de este estudio fue investigar los efectos in vitro de linezolid en combinación con cinco antimicrobianos antiestafilocócicos (doxiciclina,fosfomicina, levofloxacino, rifampicina y vancomicina) en cepas de Staphylococcus aureus sensibles a meticilina (SASM). Se utilizaroncinco cepas de SASM (hf008, hf095, hf295, hf602 y hf946) aisladas de muestras procedentes de infecciones humanas. Se utilizó el métododel damero para evaluar la sinergia entre linezolid y los cinco antimicrobianos, y se trazaron curvas de tiempo-muerte con las combinacionesmás activas. El resultado más habitual para las combinaciones de linezolid con rifampicina, vancomicina y doxiciclina fue indiferencia.La combinación con levofloxacino produjo antagonismo en dos de las cinco cepas. Sin embargo, frente a cuatro cepas se observó sinergiacon la combinación de linezolid y fosfomicina, con un índice de concentración inhibitoria fraccionada (ICIF) >0,5. Ni linezolid ni fosfomicinaen solitario inhibieron el crecimiento a 1/4x CMI, pero la combinación de ambos fármacos a 1/4 de la CMI respectiva mostró un efecto bacteriostáticosinérgico, un descenso de 2-3 log10 respecto al antimicrobiano más activo en solitario. En resumen, la combinación de linezolid yfosfomicina a concentraciones subinhibitorias se mostró sinérgica, ejerciendo un efecto bacteriostático

The objective of this paper was to investigate the in vitro effects of linezolid combined with five antistaphylococcal antibiotics – doxycycline,fosfomycin, levofloxacin, rifampicin and vancomycin – upon methicillin-susceptible Staphylococcus aureus (MSSA). Five MSSA isolates fromclinical specimens of human infections – hf008, hf095, hf295, hf602 and hf946 – were used in this study. The checkerboard method wasused to assess synergism between linezolid and the five antibiotics, and time-kill curves were carried out with the most active combinations.Indifference was the most common result achieved by the checkerboard method when linezolid was combined with rifampicin, vancomycinor doxycycline. The combination with levofloxacin yielded antagonism for two of the five isolates. However, four isolates showed synergyfor the combination of linezolid plus fosfomycin with a fractional inhibitory concentration index (FICI) >0.5. Neither linezolid nor fosfomycinalone inhibited growth at 1/4x minimum inhibitory concentration (MIC); but the combination of both drugs at 1/4 the respective MICshowed a synergistic bacteriostatic effect, a 2–3 log10 decrease with respect to the most active antibiotic alone. In summary, the combinationof subinhibitory concentrations of linezolid and fosfomycin presented synergism, exerting a bacteriostatic effect

Barttin is a Cl- channel beta-subunit crucial for renal Cl- reabsorption and inner ear K+ secretion.

Renal salt loss in Bartter's syndrome is caused by impaired transepithelial transport in the loop of Henle. Sodium chloride is taken up apically by the combined activity of NKCC2 (Na+-K--2Cl- cotransporters) and ROMK potassium channels. Chloride ions exit from the cell through basolateral ClC-Kb chloride channels. Mutations in the three corresponding genes have been identified that correspond to Bartter's syndrome types 1-3. The gene encoding the integral membrane protein barttin is mutated in a form of Bartter's syndrome that is associated with congenital deafness and renal failure. Here we show that barttin acts as an essential beta-subunit for ClC-Ka and ClC-Kb chloride channels, with which it colocalizes in basolateral membranes of renal tubules and of potassium-secreting epithelia of the inner ear. Disease-causing mutations in either ClC-Kb or barttin compromise currents through heteromeric channels. Currents can be stimulated further by mutating a proline-tyrosine (PY) motif on barttin. This work describes the first known beta-subunit for CLC chloride channels and reveals that heteromers formed by ClC-K and barttin are crucial for renal salt reabsorption and potassium recycling in the inner ear.

Sequential amino acid exchange across b(0,+)-like system in chicken brush border jejunum.

In the small intestine, cationic amino acids are transported by y(+)-like and b(0,+)-like systems present in the luminal side of the epithelium. Here, we report the characterization of a b(0,+)-like system in the apical membrane of the chicken jejunum, and its properties as an amino acid exchanger. Analysis of the brush border membrane by Western blot points out the presence of rBAT (protein related to b0,+ amino acid transport system) in these membranes. A functional mechanism for amino acid exchange across this system was established by kinetic analysis measuring fluxes at varying substrate concentrations both in internal (in) and external (out) vesicle compartments. This intestinal b(0,+)-like system functions for L-arginine as an obligatory exchanger since its transport capacity increases 100-200 fold in exchange conditions, thus suggesting an important role in the intestinal absorption of cationic amino acids. The kinetic analysis of Argin efflux velocities is compatible with the formation of a ternary complex and excludes a model involving a ping-pong mechanism. The binding affinity of Argout is higher than that of Argin, suggesting a possible order of binding (Argout first) for the formation of the ternary complex during the exchange cycle. A model of double translocation pathways with alternating access is discussed.

Phase II of doxorubicin/taxol in metastatic breast cancer. Argentine Multicenter Taxol Group.

PURPOSE: To assess the response rate, survival, and toxicity of Taxol (paclitaxel) as 1-h infusion plus doxorubicin as first-line treatment for patients with metastatic breast cancer (MBC). PATIENTS AND METHODS: Seventy-six patients with untreated MBC were recruited. All of them had measurable disease and were evaluable for toxicity. Fifty-five percent of the patients had visceral involvement. The dose of doxorubicin was fixed at 50 mg/m2 as a short intravenous infusion, followed by 200 mg/m2 of Taxol as a 1-h intravenous infusion. Doxorubicin was administered during the first seven cycles, continuing with Taxol only up to a maximum of ten cycles. RESULTS: Neutropenia was the most important toxicity: 30% grade 3 and 18% grade 4. Only 2 patients showed a decrease in the left ventricular ejection fraction (LVEF) which caused discontinuing the treatment. No clinical congestive heart failure (CHF) was observed. Seventy-four patients were eligible for response evaluation: 10 (14%) achieved complete response (CR) and 46 (62%) achieved partial response (PR). The mean duration of response was 13.47+/-1.35 months (95% confidence interval (CI): 10.82; 16.12) and the mean survival was 21.50+/-1.42 months (95% CI: 18.72; 24.29). CONCLUSION: The overall response (OR) rate was 76%. No CHF was assessed and 2 patients stopped treatment due to LVEF decrease. Although doxorubicin 50 mg/m2 followed by Taxol 200 mg/m2 in 1-h intravenous infusion presents a toxicity profile which demands a close follow-up, it represents a convenient outpatient schedule with similar activity rate compared to longer Taxol infusions.