ABSTRACT
Mesenchymal chondrosarcoma is a rare subset of sarcomas accounting for 3%-10% of all cases of chondrosarcomas. Radical resection is the only curative strategy, even in patients with metastatic tumors. However, data regarding treatment strategies remain limited owing to the small number of cases. Herein, we report a patient who underwent repeated robotic pancreatectomy for recurrent pancreatic metastasis originating from extraskeletal mesenchymal chondrosarcoma of the pelvis. First, robotic pancreaticoduodenectomy with a reconstruction of pancreaticogastrostomy was performed for synchronous pancreatic metastasis 5 months after the primary resection of mesenchymal chondrosarcoma. Ten months after robotic pancreaticoduodenectomy, tumor recurrence was observed at the tail end of the pancreas, which was removed by reperforming robotic distal pancreatectomy. Given the precise tissue manipulation that can be achieved with robotic articulated forceps, the peripheral splenic artery and pancreas were easily isolated and divided in close proximity to the tumor. The central part of the pancreas was preserved. Robotic surgery allowed safe and effective resection of the reconstructed remnant pancreas. The patient survived for 28 months after primary tumor resection. Repeated pancreatectomy with minimally invasive techniques is a feasible and curative treatment for metastatic mesenchymal chondrosarcoma.
Subject(s)
Chondrosarcoma, Mesenchymal , Neoplasms, Second Primary , Pancreatic Neoplasms , Robotic Surgical Procedures , Humans , Pancreatectomy/methods , Robotic Surgical Procedures/methods , Chondrosarcoma, Mesenchymal/surgery , Neoplasm Recurrence, Local/surgery , Pancreatic Neoplasms/surgery , Pancreatic Neoplasms/pathology , Pancreaticoduodenectomy/methods , Neoplasms, Second Primary/surgeryABSTRACT
The aim of this trial was to carry out a bioequivalence (BE) study in dogs using a generic preparation of amoxicillin-potassium clavulanate vs a commercially available reference preparation, both claiming to achieve plasma concentrations that allow a 12 h dosing interval after oral administration. The oral pharmacokinetic profiles of a single dose of each preparation were carried out in 12 adult mongrel dogs in a crossover model with a 10 day washout period at a dose of 12.5 mg/kg of trihydrate amoxicillin and potassium clavulanate as tablets. A composite determination of amoxicillin-potassium clavulanate concentration in each sample of plasma was carried out in triplicate, using a microbiological agar diffusion analysis. Pharmacokinetic analysis was carried out with a non-compartmental model. Statistical analysis of pharmacokinetic variables was carried out by ANOVA and Bonferroni t test, setting a P < 0.05. In accordance with international standards, it was found that the generic preparation failed to be bioequivalent, i.e: AUC0-∞ 9.08 ± 0.26 μg h/ml and Cmax 5.48 ± 0.19 μg/ml for the generic preparation vs AUC0-∞ 13.28 ± 0. 30 μg h/ml and Cmax 2.9 ± 0.17 μg/ml for the reference one. A 0.25 μg/ml breakpoint can be set as minimum effective plasma concentration for amoxicillin; hence the generic preparation requires a dose interval of eight h.
El objetivo de este trabajo fue determinar la bioequivalencia entre dos preparados comerciales de amoxicilina-ácido clavulánico disponibles en forma de tableta para uso oral en perros, y cuyo intervalo de dosificación indicado por los fabricantes es de 12 horas. Se calculó el perfil farmacocinético de cada preparado, a una dosis oral de 12.5 mg/kg de amoxicilina y ácido clavulánico en doce perros adultos mediante un modelo cruzado. Se determinó la concentración activa de la combinación de ambos fármacos en cada muestra de plasma, utilizando un método de análisis microbiológico por difusión en agar. El cálculo farmacocinético se llevó a cabo con un modelo no compartamental y los valores obtenidos se analizaron mediante un ANDEVA y prueba T de Bonferroni, con una P < 0.05. Tomando en cuenta las pautas internacionales, la formulación genérica resultó no ser bioequivalente a la de referencia. Esto es, se obtuvieron valores de AUC0-∞ 9.08 ± 0.26 μg h/ml y Cmax 5.48 ± 0.19 μg/ml para el genérico vs AUC0-∞ 13.28 ± 0. 30 μg h/ml y Cmax 2.9 ± 0.17 μg/ml para el de referencia. Si se considera un punto de inflexión para bacterias susceptibles, de 0.25 μg/ml, el preparado genérico requiere un intervalo de dosificación de ocho horas.
ABSTRACT
Pharmacokinetic variables of amikacin in cows were determined after administration of amikacin sulphate either intravenously (IV) or intramuscularly (IM) at a dose of 25 mg/kg per day for three days. Amikacin concentrations at time zero and maximum serum concentrations were 240.8 microg/mL and 122.53 microg/mL, respectively. The elimination half-life remained unchanged during the three days of administration (T1/2beta = 1.33 +/- 0.029 h for the IV route and T1/2beta = 2.75 +/- 0.38 h for the IM route). Apparent volumes of distribution suggest limited distribution out of the central compartment (VdAUC = 0.154 +/- 0.005 L/kg; Vdc = 36.50 +/- 2.35 L; Vdss = 0.092 +/- 0.004 L/kg). Bioavailability after IM administration was 95%. Serum profiles of urea, creatinine, albumin, electrolytes and pH after 5-day treatment with amikacin at a dose of 25 mg/kg per day IM revealed no changes. Assessment of diffusion of amikacin to milk by a commercially available screening method to detect antibiotic residues revealed that amikacin could not be detected by the fifth milking period after the last treatment. These results suggest that it would be rational to use a large single-daily dose of amikacin for future clinical trials in cows.
