Differences in intraoperative and surgical outcomes between normotensive pheochromocytomas and sympathetic paragangliomas (PPGLs) and hypertensive PPGLs: results from the PHEO-RISK STUDY.

PURPOSE: To compare the intraoperative and surgical outcomes of normotensive pheochromocytomas and sympathetic paragangliomas (PPGLs), hypertensive PPGLs and non-PPGL adrenal lesions. METHODS: This a retrospective multicenter cohort study of patients with PPGLs from 18 tertiary hospitals. A control group of histologically confirmed adrenocortical adenomas (non-PPGL group) was selected to compare intraoperative and surgical outcomes with of the normotensive PPGLs. RESULTS: Two hundred and ninety-six surgeries performed in 289 patients with PPGLs were included. Before surgery, 209 patients were classified as hypertensive PPGLs (70.6%) and 87 as normotensive PPGLs. A higher proportion of normotensive PPGLs than hypertensive PPGLs did not receive alpha presurgical blockade (P = 0.009). When we only considered those patients who received presurgical alpha blockers (200 hypertensive PPGLs and 76 normotensive PPGLs), hypertensive PPGLs had a threefold higher risk of intraoperative hypertensive crisis (OR 3.0 [95% 1.3-7.0]) and of hypotensive episodes (OR 2.9 [95% CI 1.2-6.7]) than normotensive PPGLs. When we compared normotensive PPGLs (n = 76) and non-PPGLs (n = 58), normotensive PPGLs had a fivefold higher risk of intraoperative complications (OR 5.3 [95% CI 1.9-14.9]) and a six times higher risk of postoperative complications (OR 6.1 [95% CI 1.7-21.6]) than non-PPGLs. CONCLUSION: Although the risk of intraoperative hypertensive and hypotensive episodes in normotensive PPGLs is significantly lower than in hypertensive PPGLs, normotensive PPGLs have a greater risk of intraoperative and postoperative complications than non-PPGL adrenal lesions. Therefore, it is recommended to follow the standard of care for presurgical and anesthetic management of PPGLs also in normotensive PPGLs.

Tumour size in adrenal tumours: its importance in the indication of adrenalectomy and in surgical outcomes-a single-centre experience.

OBJECTIVE: To evaluate the relevance of tumour size in adrenal tumours in the estimation of malignancy risk and in the outcomes of adrenalectomy. METHODS: We evaluate the histological results and surgical outcomes (intraoperative and postsurgical complications) in a retrospective single-centre cohort of patients without history of active extraadrenal malignancy with adrenal tumours consecutively operated in our centre during January 2010 and December 2020. We compared these results in lesions smaller and larger than 40, 50, and 60 mm. RESULTS: Of 131 patients with adrenal tumours who underwent adrenalectomy, 76 (58.0%) had adrenal masses measuring ≥ 40 mm; 47 were > 50 mm and 28 > 60 mm. The final diagnosis was adrenocortical carcinoma (ACC) in 7 patients, pheochromocytoma in 35, and benign lesions in the remaining. All patients with ACC had adrenal masses > 50 mm, with Hounsfield units > 40 and low lipidic content in the CT. The risk of ACC and pheochromocytoma increased as tumour size did. The diagnostic accuracy of tumour size was quite good for the prediction of ACC (AUC-ROC 0.883). Nevertheless, when only adrenal tumours with HU < 40 were considered, the risk of ACC was 0% independent of tumour size. For pheochromocytomas, the risk was of 8.6% independent of tumour size for lesions with < 20HU. The risk of intraoperative and postoperative complications was independent of tumour size. CONCLUSION: Risk of malignancy and of pheochromocytoma increased as tumour size increased, but, in the presurgical estimation of malignancy risk and of pheochromocytoma, not only tumour size, also lipidic content and other radiological features, should be considered. The risk of complications was independent of tumour size, but hospital stay was longer in patients with complication or open approach.

Protocol for presurgical and anesthetic management of pheochromocytomas and sympathetic paragangliomas: a multidisciplinary approach.

OBJECTIVE: To offer a practical guide for the presurgical and anesthetic management of pheochromocytomas and sympathetic paragangliomas (PGLs). METHODS: This protocol was based on a comprehensive review of the literature and on our own multidisciplinary team's experience from managing pheochromocytoma and sympathetic PGLs at a referral center. RESULTS: Patients with pheochromocytomas and sympathetic paragangliomas (PGLs) may develop potentially life-threatening complications, especially during surgical procedures. A complete biochemical, radiological, genetic, and cardiological assessment is recommended in the preoperative stage as it provides an evaluation of the risk of surgical complications and malignancy, allowing individualization of the presurgical treatment. Treatment with α-blockade and proper volume expansion in the preoperative stage significantly reduces the perioperative morbidity. During surgery, the anesthesiologist should look for a deep anesthetic level that inhibits the cardiovascular effects of catecholamines to minimize the risk of intraoperative complications. CONCLUSIONS: An optimal presurgical evaluation of pheochromocytomas/ sympathetic PGL requires a multidisciplinary approach, including a complete hormonal, radiological, cardiac, genetic, and functioning evaluation in most cases. A proper preoperative evaluation in combination with strict blood pressure and heart rate control, and blood volume status optimization, will significantly reduce the risk of intraoperative and perioperative complications. In those patients who unfortunately develop intraoperative complications, the role of the anesthesiologist is essential since the selection of the appropriate management has a direct impact on morbimortality reduction.

Intelligent-assistant system for scleral spur location.

A system based on the use of two artificial neural networks (ANNs) to determine the location of the scleral spur of the human eye in ocular images generated by an ultrasound biomicroscopy is presented in this paper. The two ANNs establish a relationship between the distance of four manually placed landmarks in an ocular image with the coordinates of the scleral spur. The latter coordinates are generated by the expert knowledge of a subject matter specialist. Trained ANNs that generate good results for scleral spur location are incorporated into a software system. Statistical indicators and results yield an efficiency performance above 95%.

Understanding the antimicrobial properties/activity of an 11-residue Lys homopeptide by alanine and proline scan.

Previous work demonstrated that lysine homopeptides adopt a polyproline II (PPII) structure. Lysine homopeptides with odd number of residues, especially with 11 residues (K11), were capable of inhibiting the growth of a broader spectrum of bacteria than those with an even number. Confocal studies also determined that K11 was able to localize exclusively in the bacterial membrane, leading to cell death. In this work, the mechanism of action of this peptide was further analyzed focused on examining the structural changes in bacterial membrane induced by K11, and in K11 itself when interacting with bacterial membrane lipids. Moreover, alanine and proline scans were performed for K11 to identify relevant positions in structure conformation and antibacterial activity. To do so, circular dichroism spectroscopy (CD) was conducted in saline phosphate buffer (PBS) and in lipidic vesicles, using large unilamellar vesicles (LUV), composed of 2-dimyristoyl-sn-glycero-3-phosphoglycerol (DMPG) or bacterial membrane lipid. Antimicrobial activity of K11 and their analogs was evaluated in Gram-positive and Gram-negative bacterial strains. The scanning electron microscopy (SEM) micrographs of Staphylococcus aureus ATCC 25923 exposed to the Lys homopeptide at MIC concentration showed blisters and bubbles formed on the bacterial surface, suggesting that K11 exerts its action by destabilizing the bacterial membrane. CD analysis revealed a remarkably enhanced PPII structure of K11 when replacing some of its central residues by proline in PBS. However, when such peptide analogs were confronted with either DMPG-LUV or membrane lipid extract-LUV, the tendency to form PPII structure was severely weakened. On the contrary, K11 peptide showed a remarkably enhanced PPII structure in the presence of DMPG-LUV. Antibacterial tests revealed that K11 was able to inhibit all tested bacteria with an MIC value of 5 µM, while proline and alanine analogs have a reduced activity on Listeria monocytogenes. Besides, the activity against Vibrio parahaemolyticus was affected in most of the alanine-substituted analogs. However, lysine substitutions by alanine or proline at position 7 did not alter the activity against all tested bacterial strains, suggesting that this position can be screened to find a substitute amino acid yielding a peptide with increased antibacterial activity. These results also indicate that the PPII secondary structure of K11 is stabilized by the interaction of the peptide with negatively charged phospholipids in the bacterial membrane, though not being the sole determinant for its antimicrobial activity.

[Genital-urinary rhabdomyosarcoma in childhood: our experience]. / Rabdomiosarcoma genitourinario en la infancia, nuestra experiencia.

INTRODUCTION: Rhabdomyosarcoma (RSM) becomes the most common tumour of the soft tissues during the paediatric age. It represents among 2-3% of child tumours. The genital-urinary location is the second most common location, only after head and neck. The treatment is usually medical, being the surgery a mere contribution, except for the cases in which the situation is not under control, when very aggressive surgery is necessary. The aim of this study is to analyse the cases of genial-urinary RMS that have been treated in our centre and the role that surgery has in their treatment. MATERIAL AND METHODS: Retrospective study of 20 patient (7 girls and 13 boys) with a median age of 24 months (range from 1 month to 12 years) with RMS in the aurochs-genial tract who have been treated in our hospital from 1990 to 2012. The variables described are demographic, location of the primary tumour, state at diagnosis, received treatment, both medical and surgical, with greater emphasis on the kind of surgery applied and monitoring in terms of survival. RESULTS: The location of the primary tumour was: bladder (6), paratesticular (5), vagina (3) retroperitoneal space (3), lesser pelvis (2) and prostate (1). All of them received medical treatment with chemotherapy and radiotherapy following International Society of Pediatric Oncology protocol after diagnostic biopsy. Surgery, which was always used as help, was: reappraisal of biopsy (1), orchiectomy (5), tumoral resection (8) and radical surgery (cystoprostatectomy or pelvic exenteration) in 6 patients. There were 3 deaths, 2 because of the evolution of the disease and 1 because of postoperative sepsis. The survival rate is 80% with a median follow - up of 14 years. CONCLUSIONS: The RMS is the most common tumour of soft tissues in childhood and the genital-urinary location is the second most common after the parameningeal one. The treatment is multidisciplinary and the surgery has a contributing role when there is no answer to the medical treatment or when there is a residual tumour even if some patients do not respond to medical treatment and they need a radical surgery for recovery.

INTRODUCCION: El rabdomiosarcoma (RMS) constituye el tumor de tejidos blandos más frecuente en la edad pediátrica, representando el 2-3% de los tumores infantiles. La localización genitourinaria es la segunda en frecuencia tras la cabeza y cuello. El tratamiento suele ser médico, quedando la cirugía como coadyuvante, excepto en casos no controlados en que se precisan cirugías muy agresivas. El objetivo del estudio es analizar los casos de RMS de localización genitourinaria tratados en nuestro Centro y el papel que la cirugía tiene en su tratamiento. MATERIAL Y METODOS: Estudio retrospectivo de 20 pacientes (7 niñas y 13 niños) con una mediana de edad de 24 meses (rango de 1 mes a 12 años) con RMS del tracto urogenital tratados en nuestro Hospital desde 1990 hasta 2012. Se describen variables demográficas, localización del tumor primario, estadio al diagnóstico, tratamiento recibido, tanto médico como quirúrgico, con especial atención al tipo de cirugía realizada y seguimiento en términos de supervivencia. RESULTADOS: La localización del tumor primario fue: vejiga (6), paratesticular (5), vagina (3), retroperitoneo (3), pelvis menor (2) y próstata (1). Todos recibieron tratamiento médico con quimioterapia y radioterapia según protocolo de la Sociedad Internacional de Oncología Pediátrica (SIOP) previa biopsia diagnóstica. La cirugía, practicada en todos los casos como coadyuvante fue: reevaluación por biopsia (1), orquiectomía (5), resección tumoral (8) y cirugía radical (cistoprostatectomía o exanteración pélvica) en 6 pacientes. Hubo 3 fallecimientos, 2 por progresión de la enfermedad y 1 por sepsis postoperatoria. Los 17 restantes están vivos, lo que supone una supervivencia del 80% con una mediana de seguimiento de 14 años. CONCLUSIONES: El RMS es el tumor de tejidos blandos más frecuente en la infancia y la localización genitourinaria la segunda en frecuencia tras las parameníngeas. El tratamiento es multidisciplinar y la cirugía tiene un papel coadyuvante en casos de no respuesta al tratamiento médico o de tumor residual aunque hay pacientes que no responden al tratamiento médico y precisan de cirugía radical para su curación.

[Therapeutic approach in urinary tract stones in children]. / Abordaje de la litiasis en tracto urinario en niños.

PURPOSE: Kidney stone disease in children is a rare pathology, with a low incidence in Spain (1/4,500 hospitalized children). The spontaneous expulsion rate is about 34-47% which means that more of 50% of children need active treatment. Paediatric patients forming urinary stones have a high risk of recurrence, therefore, a standard diagnosis and treatment are needed. We present our experience in urolithiasis treatment in children. MATERIALS AND METHODS: We reviewed retrospectively all the patients ≤ 16 years hospitalized in our hospital with urolithiasis diagnosis from 2000 to 2013, citing treatment modality, stone-free rates and complications. RESULTS: A total of 69 patients with a mean age of 8,2 years (range 1-16 years) were treated in our hospital during that period. The main clinical presentation was pain (52%). The diagnosis was made by abdominal ultrasounds in all cases. About localization, 21 lithiasis were found in distal urether (UD), 8 in medium urether (UM), 3 in proximal urether (UP) and 13 in renal pelvis (PR). The mean size was 13 mm. 21 (30%) patients had a spontaneous expulsion of the stone, 14 (20%) patients were treated with extracorporeal shock wave lithotripsy and in 22 (32%) patients the elected therapy was ureterosopic stone fragmentation (n = 13) or removal (n = 9). No complications were observed. The overall stone-free rate was 79% (n = 55). CONCLUSIONS: Kidney stone disease in children is a rare pathology, with its own features about diagnosis and treatment, which requires medical care in a specialized center. The optimal treatment should be considered regarding the age of the patient, localization and size of the stone, as well as the team experience.

Is extracorporeal lithotripsy a first-line treatment for urinary stones today?

OBJECTIVE: To evaluate the efficacy and complications of extracorporeal lithotripsy (SWL) as a first-line treatment for renal and ureteral stones METHODS: Retrospective and observational study of all the patients treated with lithotripsy in a third level center between January 2014 and January 2021; characteristics of the patients, the stones, complications and results of SWL is recollected. Multivariate logistic regression of the factors associated with stone size reduction was performed. A statistical analysis of the factors associated with additional treatment after SWL and factors associated with complications is also executed. RESULTS: 1727 patients are included. Stone mean size was 9,5mm. 1540 (89.4%) patients presented reduction in stone size. In multivariate analysis, stone size (OR=1.13; p=0.00), ureteral location of the lithiasis (OR=1.15; p=0.052) and number of waves (p=0.002; OR=1.00) used in SWL are the factors associated with reduction of stone size. Additional treatment after lithotripsy was needed in 665 patients (38.5%). The factors associated with the need for retreatment were stone size (OR=1.131; p=0.000), number of waves (OR=1.000; p=0.000), energy (OR=1.005; p=0.000). 153 patients (8.8%) suffered complications after SWL. A statistically significant association was found between the size of the lithiasis (p=0.024, OR=1.054) and the previous urinary diversion (P=0.004, OR=0.571). CONCLUSION: Lithotripsy remains an effective treatment as the first line of therapy for reno-ureteral lithiasis with a low percentage of complications.

Surgical and postsurgical management of abdominal paragangliomas and pheochromocytomas.

PURPOSE: To describe our current protocol for surgical and postsurgical management of abdominal paragangliomas (PGLs) and pheochromocytomas, with a special focus on multidisciplinary management in centres with experience. METHODS: The physicians involved in the management of patients with abdominal PGLs and pheochromocytomas of our hospital reviewed systematically current knowledge on the surgical management of abdominal PGLs and pheochromocytomas. RESULTS: Currently, surgery is considered the treatment of choice for abdominal PGLs and pheochromocytomas. The choice of surgical approach is determined based on the location of the lesion, size, patient́s body habitus and the likelihood of malignancy. Laparoscopic surgery is usually considered the gold standard approach for pheochromocytomas, but open access should be considered in invasive and/or potentially malignant tumours >8-10 cm and for abdominal PGLs. Postsurgical management of pheochromocytomas and PGLs includes close hemodynamic monitoring and treatment of postsurgical complications, the pathological study of the surgical specimen, reassessment of hormonal and/or radiological status and planning of follow-up based on the risk of recurrence and malignancy. CONCLUSION: Surgery represents the treatment of choice of most abdominal PGLs and pheochromocytomas. Optimal postsurgical evaluation, including hemodynamic, pathological, hormonal, and radiological evaluation, should be performed by a multidisciplinary team specializing in PGL/pheochromocytoma management.

Extracorporeal shock wave lithotripsy for lower calyx stones: predicting treatment success.

INTRODUCTION: The use of extracorporeal shock wave lithotripsy (ESWL) for lower calyx stones is associated with a high rate of residual fragments. Our aim is to analyse the effectiveness and complications of ESWL for lower calyx stones. METHODS: Retrospective review of patients with lower renal calyx stones treated with ESWL between January-2014 and December-2020. Measurement of infundibular length, infundibular width and infundibulopelvic angle in lower renal pole to determine favourable anatomy. ESWL failure: fragments >3 mm detected in plain abdominal film, CT scan and/or renal ultrasound 3 months after treatment. Complications after ESWL, auxiliary procedures along with risk factors associated with perirenal haematoma were analysed. SPSS statistical software was used. RESULTS: 512 patients with lower calyx stones were treated with ESWL. 80.3% of patients had a favourable anatomy. Overall stone-free rate was 70.5%. Regarding main complications after ESWL, stainstrasse was described in 5 patients and urinary tract infection in 3 patients. 10 perirenal haematomas (2%) were reported. Statistical association was found between antiplatelet treatment and the risk of perirenal haematoma (p = 0.004). Logistic binary regression proved the association between unfavourable anatomy of the lower renal pole (p = 0.000), size of the stone (p = 0.001), number of shock waves (p = 0.003), energy applied (p = 0.038) and the need for additional treatment after ESWL. CONCLUSIONS: ESWL can still be considered as the initial treatment option for lower renal pole stones. The size of the stone, an unfavourable anatomy of the lower renal calyx, number of shock waves and energy applied can help predict the need for additional treatment.

Impact of the COVID-19 pandemic on the surgical activity of Pediatric Urology: analysis of postoperative complications according to the Clavien-Dindo classification. / Repercusión de la pandemia COVID-19 sobre la actividad quirúrgica de Urología Pediátrica: análisis de las complicaciones posquirúrgicas según la clasificación de Clavien-Dindo.

INTRODUCTION AND OBJECTIVE: The coronavirus disease 2019 (COVID-19) has caused a pandemic of global impact that forced social-political measures to be taken, such as the declaration of the state of alarm in Spain. At the same time, the reorganization of the pediatric medical-surgical activities and infrastructures was carried out, with the consequent suspension of the non-urgent surgical activity of Pediatric Urology. We analyzed the impact of the COVID-19 pandemic on surgical activity in a Pediatric Urology division, as well as surgical complications according to the Clavien-Dindo classification. MATERIALS AND METHODS: A systematic review of epidemiological, clinical and surgical data was carried out, including complications and readmissions of all patients operated on in the division of Pediatric Urology within the duration of the state of alarm. Five time periods have been created according to the de-escalation phases. RESULTS: Forty-nine surgical procedures were carried out on 45 patients (8 prior to the implementation of the de-escalation phases). High priority pathologies were the most frequent in the first phases, being the ureteropelvic junction (UPJ) obstruction the most prevalent. Four complications were recorded (8.8%), none of them were respiratory. CONCLUSIONS: The EAU recommendations for the resumption of surgical activity have allowed a correct, safe and gradual transition to the routine surgical activity in Pediatric Urology. The Clavien-Dindo classification is useful and valid for application in this division. No respiratory complications have been reported that could be attributable to the pandemic situation.

Microinjection of a conserved peptide sequence of p34cdc2 induces a Ca2+ transient in oocytes.

The product of the yeast cell cycle control gene cdc2, and its homologs in higher eukaryotes (p34cdc2), all contain a perfectly conserved sequence of 16 amino acids that has not been found in any other protein sequence. Microinjection of this peptide triggers a specific increase in the concentration of intracellular free Ca2+ that originates from intracellular stores in both starfish and Xenopus oocytes. Thus, p34cdc2 might interact through its conserved peptide domain with some component of the Ca2(+)-regulatory system.

Separation and preconcentration by a cloud point extraction procedure for determination of metals: an overview.

Recently, cloud point extraction (CPE) has been an attractive subject as an alternative to liquid-liquid extraction. The technique is based on the property of most non-ionic surfactants in aqueous solutions to form micelles and become turbid when heated to the cloud point temperature. This review covers a selection of the literature published on applications of CPE in determination of metal ions over the period between 2004 and 2008.

Technical challenges of endoscopic treatment for vesicoureteral reflux after Cohen reimplantation. / Consideraciones técnicas en el tratamiento endoscópico del reflujo vesicoureteral tras reimplante tipo Cohen.

INTRODUCTION: The range of indications for endoscopic treatment of vesicoureteral reflux opens more and more until including correction of secondary reflux (VUR) after ureteral reimplantation. However these cases suppose a technical challenge due to postoperative changes. The aim of this work is to present our experience on endoscopic treatment for VUR in ureteral units with Cohen reimplantation surgery, with special interest in the technical peculiarities of the procedure. MATERIAL AND METHODS: A retrospective study of cases of secondary VUR after reimplantation surgery treated by subureteral injection. TECHNIQUE: We put the needle perpendicular to submucous tunnel and inject medially to hole forming a wheal on the anterior face that occludes the meatus RESULTS: During the 1993-2016 period 21 injections were performed in 15 ureteral units. The ureteral pathology included primary VUR (4), duplex system with lower pole reflux (4), megaureter (3) and ureterocele (2). Average patient age was 5.7 years old (2-12). Succesful outcome had been got in 10 ureteral units (66.67%), a decrease of VUR grade in 4 (26.67%) and perseverance/no resolution of grade IV VUR in 1 (6.67%) DISCUSSION: The anti-reflux mechanism of reimplantation depends on optimizing the submucosous tunnel. This subgroup of pacients is small and there are few studies, hindering the agreement on the most appropiate technique. CONCLUSION: Endoscopic treatment of secondary reflux after reimplantation surgery is a procedure with certain technical feature, but safe and effective offering an alternative prior to surgical reoperation.

Recent advances in analytical determination of thalidomide and its metabolites.

Thalidomide, a racemate, is coming into clinical use as immuno-modulating and anti-inflammatory drug. Thalidomide was approved by the FDA in July 1998 for the treatment of erythema nodusum leprosum associated with leprosy. Recently, thalidomide is proving to be a promising drug in the treatment of a number of cancers and inflammatory diseases, such as multiple myeloma, inflammatory bowel disease (Crohn's disease), HIV and cancer associated cachexia. These effects may chiefly be exerted by S-thalidomide, but the enantiomers are inter-converted in vivo. Thalidomide is given orally, although parenteral administration would be desirable in some clinical situations. Thalidomide has been determined in formulations and, principally in biological fluids by a variety of methods such as high-performance liquid chromatography with ultraviolet detection and liquid chromatography coupled with tandem mass spectrometry. The overview includes the most relevant analytical methodologies used in its determination.

Analytical methodologies for the determination of cisplatin.

cis-Diamminedichloroplatinum(II) (cisplatin) is a important chemotherapeutic drug for cancer treatment since 1978. Unfortunately, because of the severe side-effects like nephrotoxicity, ototoxicity, etc., they are administered in small doses at low concentration establishing the maximum limit dosage to 100 mg/m(2) (21 days). A variety of analytical methods have been proposed for the determination of cisplatin in biological fluids and tissues that permit the accurate determination at or below the part per billion level in the native sample. The purpose of the current review is to provide a systematic survey of the latest analytical techniques for the determination of cisplatin in biological samples.

Recent developments in analytical determination of furosemide.

Furosemide (FUR), a drug that promotes urine excretion, is used in the pharmacotherapy of various diseases and is considered as a doping agent in sports. FUR is a powerful diuretic (water pill). This medicine is used to treat excessive fluid accumulation and swelling (edema) of the body caused by heart failure, cirrhosis, chronic kidney failure, and nephrotic syndrome. Owing to its extensive use as a powerful diuretic, FUR has long attracted the attention of many analysts. A variety of analytical methods have been proposed for the determination of FUR in biological fluids and pharmaceutical samples. The revision includes the most relevant analytical methodologies used in its determination from the nineties decade at present.

Analytical methodologies for the determination of sertraline.

Sertraline is a widely used antidepressant belonging to the selective serotonin reuptake inhibitor class; its efficacy has been demonstrated not only in the treatment of major depression, obsessive compulsive and panic disorders, but also for eating, premenstrual dysphoric and post-traumatic stress disorders. Several methods have been published for the determination of sertraline in pharmaceuticals, biological materials and environmental samples. The purpose of the current review is to provide a systematic survey of the latest analytical techniques for the determination of sertraline covering the period from 1987 until 2008.

Factors involved in the late failure of endoscopic treatment of vesicoureteral reflux. / Factores implicados en el fracaso tardío del tratamiento endoscópico del reflujo vesicoureteral.

INTRODUCTION: The short-term results of endoscopic treatment of vesicoureteral reflux (VUR) are excellent. Over time, however, a number of patients have been identified for whom VUR reappeared after being resolved with this technique. The aim of this study was to analyse the factors related to this event. MATERIAL AND METHODS: A retrospective, analytical, case-control study included 395 ureteral units with primary VUR treated successfully at our centre, with a minimum follow-up of 3 years. We identified cases in which VUR reappeared and analysed the demographic variables, those related to VUR (grade, laterality, initial study) and those related to the operation (materials used). RESULTS: We identified 77 ureteral units with recurrence in the 395 included units (19.5%). The recurrence rate was 29.7% for the patients treated with dextranomer/hyaluronic acid (Dx/HA), 20.2% for those treated with polydimethylsiloxane (MP) and 12.2% for polytetrafluoroethylene (PTFE). The onset of recurrence rose to 35% for patients treated before 1 year of age and those with gradeV VUR. Urinary dysfunction symptoms also increased the recurrence rate to 34.9%. CONCLUSION: The use of resorbable dextranomer/hyaluronic acid material was related to recurrence in the endoscopic treatment of VUR. The high-grade reflux and treatment at an early age, as well as the presence of urinary dysfunction, are also factors associated with recurrence.

Morphine and its metabolites: analytical methodologies for its determination.

The present article reviews the methods of determination published for morphine and its metabolites covering the period from 1980 until at the first part of 2006. The overview includes the most relevant analytical determinations classified in the following two types: (1) non-chromatographic methods and (2) chromatographic methods.