Intracranial non-germinomatous germ cell tumors in children and adolescents: how can the experience from an uppermiddle-income country contribute to the worldwide effort to improve outcomes?

Background: Non-germinomatous germ cell tumors (NGGCT) accounts for one third of intracranial GCT. While the germinoma group have an excellent overall survival, the standard of practice for children with NGGCT is still under evaluation. Aims: Describe the results of the of the Brazilian consortium protocol. Methods: Since 2013, 15 patients with a diagnosis of NGGCT by histopathology and/or serum/cerebrospinal fluid (CSF) tumor markers, ßHCG >200mlU/ml and/or positive alpha-fetoprotein were treated with neoadjuvant chemotherapy with carboplatin, cyclophosphamide and etoposide followed by ventricular radiotherapy (RTV) of 18Gy with boost (32Gy) to the primary site. Metastatic patients underwent craniospinal irradiation (CSI) and "slow responders" to the four initial cycles of CT, to autologous stem cell transplantation (ASCT) followed by CSI. Results: Mean age, 13.1 years. Thirteen males. Primary sites: pineal (n=12), suprasellar (n=2) and bifocal (n=1). Four patients were metastatic at diagnosis. Eight patients had CSF and/or serum alpha-fetoprotein levels > 1,000ng/ml. Tumor responses after chemotherapy demonstrated complete in six cases and partial in seven, with "second-look" surgery being performed in five cases, and two patients presenting viable lesions being referred to ASCT. The main toxicity observed was hematological grades 3/4. Two patients with metastatic disease, one with Down Syndrome and AFP > 1,000ng/ml and the other with choriocarcinoma and pulmonary metastases, developed progressive disease resulting in death, as well as two other patients without evidence of disease, due to endocrinological disorders. Event-free and overall survival at 2 and 5 years were 80% and 72.7%, respectively, with a mean follow-up of 48 months (range, 7-107). Conclusions: Despite the small number of patients, in our series, treatment with six cycles of chemotherapy and RTV with focal boost for localized disease (n=11) and ACST for identified slow responders (n=2) seem to be effective strategies contributing to the overall effort to improve outcomes of this group of patients.

Outcome of Children and Adolescents With Primary Intracranial Germinoma Treated With Chemotherapy and Reduced Dose-Field Irradiation: A Prospective Brazilian Experience.

PURPOSE: This prospective Brazilian single-arm trial was conducted to determine response to chemotherapy and survival after response-based radiotherapy in children with intracranial germinomas, in the setting of a multi-institutional study in a middle-income country (MIC) with significant disparity of subspecialty care. PATIENTS AND METHODS: Since 2013, 58 patients with histologic and/or serum and CSF tumor marker evaluations of primary intracranial germ cell tumors were diagnosed; 43 were germinoma with HCGß levels ≤200 mIU/mL and five between 100 and 200 mIU/mL. The treatment plan consisted of four cycles of carboplatin and etoposide followed by 18 Gy whole-ventricular field irradiation (WVFI) and primary site(s) boost up to 30 Gy; 24 Gy craniospinal was prescribed for disseminated disease. RESULTS: Mean age 13.2 years (range, 4.7-25.5 years); 29 were males. Diagnosis was made by tumor markers (n = 6), surgery (n = 25), or both (n = 10). Two bifocal cases with negative tumor markers were treated as germinoma. Primary tumor location was pineal (n = 18), suprasellar (n = 14), bifocal (n = 10), and basal ganglia/thalamus (n = 1). Fourteen had ventricular/spinal spread documented by imaging studies. Second-look surgery occurred in three patients after chemotherapy. Thirty-five patients achieved complete responses after chemotherapy, and eight showed residual teratoma/scar. Toxicity was mostly grade 3/4 neutropenia/thrombocytopenia during chemotherapy. At a median follow-up of 44.5 months, overall and event-free survivals were 100%. CONCLUSION: The treatment is tolerable, and WVFI dose reduction to 18 Gy preserves efficacy; we have demonstrated the feasibility of successfully conducting a prospective multicenter trial in a large MIC despite resource disparity.

Diazaborines Are a Versatile Platform to Develop ROS-Responsive Antibody Drug Conjugates*.

Antibody-drug conjugates (ADCs) are a new class of therapeutics that combine the lethality of potent cytotoxic drugs with the targeting ability of antibodies to selectively deliver drugs to cancer cells. In this study we show for the first time the synthesis of a reactive-oxygen-species (ROS)-responsive ADC (VL-DAB31-SN-38) that is highly selective and cytotoxic to B-cell lymphoma (CLBL-1 cell line, IC50 value of 54.1 nM). The synthesis of this ADC was possible due to the discovery that diazaborines (DABs) are a very effective ROS-responsive unit that are also very stable in buffer and in plasma. DFT calculations performed on this system revealed a favorable energetic profile (ΔGR=-74.3 kcal mol-1 ) similar to the oxidation mechanism of aromatic boronic acids. DABs' very fast formation rate and modularity enabled the construction of different ROS-responsive linkers featuring self-immolative modules, bioorthogonal functions, and bioconjugation handles. These structures were used in the site-selective functionalization of a VL antibody domain and in the construction of the homogeneous ADC.

Chimeric Small Antibody Fragments as Strategy to Deliver Therapeutic Payloads.

Antibody-drug conjugates (ADCs) represent an innovative class of biopharmaceuticals, which aim at achieving a site-specific delivery of cytotoxic agents to the target cell. The use of ADCs represents a promising strategy to overcome the disadvantages of conventional pharmacotherapy of cancer or neurological diseases, based on cytotoxic or immunomodulatory agents. ADCs consist of monoclonal antibodies attached to biologically active drugs by means of cleavable chemical linkers. Advances in technologies for the coupling of antibodies to cytotoxic drugs promise to deliver greater control of drug pharmacokinetic properties and to significantly improve pharmacodelivery applications, minimizing exposure of healthy tissue. The clinical success of brentuximab vedotin and trastuzumab emtansine has led to an extensive expansion of the clinical ADC pipeline. Although the concept of an ADC seems simple, designing a successful ADC is complex and requires careful selection of the receptor antigen, antibody, linker, and payload. In this review, we explore insights in the antibody and antigen requirements needed for optimal payload delivery and support the development of novel and improved ADCs for the treatment of cancer and neurological diseases.

One-step enzymatic production of fatty acid ethyl ester from high-acidity waste feedstocks in solvent-free media.

This work aims to demonstrate the enzymatic production of fatty acid ethyl ester biodiesel from highly acidic feedstock in a single-step reaction, without co-solvents and avoiding the inhibition of the enzyme by ethanol and glycerol. Additionally, an empirical equation is proposed to predict the kinetics of the production reaction as a function of the used feedstock and catalyst concentration. Biodiesel production from highly acidic feedstock perform via simultaneous esterification of free fatty acids and transesterification of triacylglycerols. Enzymatic catalysis is one of the most promising alternative technologies for the biodiesel production. Increasing of the enzymatic bioactivity is crucial for the success of such process in industrial scale. Currently, stepwise addition of the alcohol or the use of co-solvents have been proposed to avoid enzyme inhibition, such strategies add downstream processes to the production. These results can be applied to the development economical-viable enzymatic production of biodiesel in industrial scale.

Laparoscopic pyeloplasty in children: Is the outcome different in children under 2 years of age?

PURPOSE: To report the outcomes of a series of children younger than 2 years with ureteropelvic junction obstruction (UPJO) who underwent laparoscopic pyeloplasty (LP), compared to children older than 2 years. PATIENTS AND METHODS: Twenty-three children (18 male) with UPJO underwent 24 Anderson-Hynes transperitoneal LPs between March 2003 and July 2007. The diagnosis of UPJO was confirmed on renal sonography and diuretic renogram. Nine children were younger than 2 years (Group 1) and 14 were older (Group 2). One child had bilateral UPJO and underwent two non-simultaneous procedures. All children were investigated with postoperative diuretic renogram and renal sonography, and the results were statistically analysed. RESULTS: LP was feasible without conversions or intraoperative complications in all 24 cases. Median age in Groups 1 and 2 was 11 months (4-24) and 74 months (27-204), respectively, (P<0.00001). No differences were found between the groups regarding median operative time, complications, technical difficulties, discharge home and follow-up. All patients in both groups experienced resolution of symptoms or obstruction. CONCLUSIONS: The LP in children younger than 2 years is highly successful with a low-rate of complications, and has the same outcomes as in older children.

Laparoscopic diagnosis and treatment of nonpalpable testis.

INTRODUCTION: Treatment of the cryptorchid testicle is justified due to the increased risk of infertility and malignancy as well as the risk of testicular trauma and psychological stigma on patients and their parents. Approximately 20% of cryptorchid testicles are nonpalpable. In these cases, the videolaparoscopic technique is a useful alternative method for diagnosis and treatment. MATERIALS AND METHODS: We present data concerning 90 patients submitted to diagnostic laparoscopy for impalpable testicles. Forty-six patients (51.1%) had intra-abdominal gonads. In 25 testicles of 19 patients, we performed a two stage laparoscopic Fowler-Stephens orchiopexy. The other 27 patients underwent primary laparoscopic orchiopexy, in a total of 29 testicles. RESULTS: We obtained an overall 88% success rate with the 2 stage Fowler-Stephens approach and only 33% rate success using one stage Fowler-Stephens surgery with primary vascular ligature. There was no intraoperative complication in our group of patients. In the laparoscopic procedures, the cosmetic aspect is remarkably more favorable as compared to open surgeries. Hospital stay and convalescence were brief. CONCLUSIONS: In pediatric age group, the laparoscopic approach is safe and feasible. Furthermore, the laparoscopic orchiopexy presents excellent results in terms of diagnosis and therapy of the impalpable testis, which is why this technique has been routinely incorporated in our Department.

Laparoscopic diagnosis and treatment of nonpalpable testis

INTRODUCTION: Treatment of the cryptorchid testicle is justified due to the increased risk of infertility and malignancy as well as the risk of testicular trauma and psychological stigma on patients and their parents. Approximately 20 percent of cryptorchid testicles are nonpalpable. In these cases, the videolaparoscopic technique is a useful alternative method for diagnosis and treatment. MATERIALS AND METHODS: We present data concerning 90 patients submitted to diagnostic laparoscopy for impalpable testicles. Forty-six patients (51.1 percent) had intra-abdominal gonads. In 25 testicles of 19 patients, we performed a two stage laparoscopic Fowler-Stephens orchiopexy. The other 27 patients underwent primary laparoscopic orchiopexy, in a total of 29 testicles. RESULTS: We obtained an overall 88 percent success rate with the 2 stage Fowler-Stephens approach and only 33 percent rate success using one stage Fowler-Stephens surgery with primary vascular ligature. There was no intraoperative complication in our group of patients. In the laparoscopic procedures, the cosmetic aspect is remarkably more favorable as compared to open surgeries. Hospital stay and convalescence were brief. CONCLUSIONS: In pediatric age group, the laparoscopic approach is safe and feasible. Furthermore, the laparoscopic orchiopexy presents excellent results in terms of diagnosis and therapy of the impalpable testis, which is why this technique has been routinely incorporated in our Department.

Prevalance of anemia and its association with cardio-renal syndrome.

BACKGROUND: Anemia is common in cardio-renal syndrome and may contribute to increase mortality. OBJECTIVE: To examine the prevalence of anemia and its relationship with cardio-renal syndrome, and to evaluate the risk factors for death. METHODS: Retrospective study with all patients admitted with congestive heart failure (CHF). The parameters as age, gender, hemoglobin (Hb), estimated glomerular filtration rate (eGFR), New York Heart Association (NYHA) functional class, ejection fraction (EF%), hospital stay, hypertension, diabetes, smoking and CHF etiology were analyzed. Anemia was defined as Hb<12 g/dL, systolic dysfunction EF<55% and renal failure was stratified according to K-DOQI classification. Statistical analysis was done by the programs EpiInfo and SPSS for windows. RESULTS: A total of 174 patients were studied. The average age was 63+/-16 years, 65.5% were males, and 18 of them (11%) were non-survivors. Anemia was observed in 45% of patients, and 82% presented some degree of renal failure. The majority of patients (87%) were classified as NYHA functional class III or IV. The average ejection fraction was 43.9+/-16.6%, and there was no difference between survivors and non-survivors (p>0.05). Mortality was not significantly higher among patients with anemia (12.4%) when comparing to those without anemia (8.3%, p=0.31). There was a progressive decrease in the level of hemoglobin as renal function decreased (p<0.05). Increased serum creatinine was a significant risk factor for death (OR=1.59, 95% CI=1.074-2.363, p=0.021), and increased EF% was a protection factor against development of death (OR=0.904, 95% CI=0.845-0.973, p=0.007). CONCLUSIONS: The prevalence of anemia is high among patients with cardio-renal syndrome but was not associated with increased mortality. Increased serum creatinine and low EF% were variables associated with death.

Urogenital involvement in the Klippel-Trenaunay-Weber syndrome: treatment options and results

OBJECTIVE: Klippel-Trenaunay-Weber syndrome (KTWS) is a congenital condition characterized by vascular malformations of the capillary, venous and lymphatic systems associated to soft tissue and bone hypertrophy in the affected areas. This syndrome may involve bladder, kidney, urethra, ureter and genitals. We report the treatment of 7 KTWS patients with urogenital involvement. MATERIALS AND METHODS: From 1995 to 2005, 7 patients with KTWS were evaluated and the charts of these patients were reviewed. RESULTS: PatientsÆ median age was 19-years (range 4 to 46-years) and only 1 was female. The clinical presentation included genital deformities in 3 cases, hematuria in 2 and urethrorragia in 2, one of which associated with cryptorchidism and phimosis. Three patients had an association of pelvic and genital malformations, including 2 patients with hematuria due to vesical lesions and 1 patient with left ureterohydronephrosis due to a pelvic mass. Two patients had urethral lesions. Treatment included endoscopic laser coagulation for 1 patient with recurrent hematuria and 1 patient with urethrorrhagia, pelvic radiotherapy for 1 patient with hematuria and circumcision in 2 patients with genital deformities. One patient required placement of a double-J catheter to relieve obstruction. Hematuria and urethrorragia were safely and effectively controlled with laser applications. Circumcision was also effective. The patient treated with radiotherapy developed a contracted bladder and required a continent urinary diversion. CONCLUSIONS: Urogenital involvement in patients with KTWS is not rare and must be suspected in the presence of hematuria or significant cutaneous deformity of the external genitalia. Surgical treatment may be warranted in selected cases.

Urogenital involvement in the Klippel-Trenaunay-Weber syndrome. Treatment options and results.

OBJECTIVE: Klippel-Trenaunay-Weber syndrome (KTWS) is a congenital condition characterized by vascular malformations of the capillary, venous and lymphatic systems associated to soft tissue and bone hypertrophy in the affected areas. This syndrome may involve bladder, kidney, urethra, ureter and genitals. We report the treatment of 7 KTWS patients with urogenital involvement. MATERIALS AND METHODS: From 1995 to 2005, 7 patients with KTWS were evaluated and the charts of these patients were reviewed. RESULTS: Patients' median age was 19-years (range 4 to 46-years) and only 1 was female. The clinical presentation included genital deformities in 3 cases, hematuria in 2 and urethrorragia in 2, one of which associated with cryptorchidism and phimosis. Three patients had an association of pelvic and genital malformations, including 2 patients with hematuria due to vesical lesions and 1 patient with left ureterohydronephrosis due to a pelvic mass. Two patients had urethral lesions. Treatment included endoscopic laser coagulation for 1 patient with recurrent hematuria and 1 patient with urethrorrhagia, pelvic radiotherapy for 1 patient with hematuria and circumcision in 2 patients with genital deformities. One patient required placement of a double-J catheter to relieve obstruction. Hematuria and urethrorragia were safely and effectively controlled with laser applications. Circumcision was also effective. The patient treated with radiotherapy developed a contracted bladder and required a continent urinary diversion. CONCLUSIONS: Urogenital involvement in patients with KTWS is not rare and must be suspected in the presence of hematuria or significant cutaneous deformity of the external genitalia. Surgical treatment may be warranted in selected cases.

The laparoscopic management of intersex patients: the preferred approach.

UNLABELLED: In the world's largest series of patients with intersex treated by laparoscopy, authors from Sao Paulo found that this technique allowed easy identification and removal of gonads. They also found that other organs could be removed and genitoplasty performed. OBJECTIVE: To present possibly the largest series of the use of laparoscopy for treating intersex patients. PATIENTS AND METHODS: Fifty intersex patients (34 with male and two with female pseudohermaphroditism, nine with gonadal dysgenesis, four with true hermaphroditism, and one with complex hypospadias), aged 0.5-46 years (mean 18.3), underwent laparoscopy to remove gonads and/or ductal structures incompatible with the social gender, or for gonadal tumour or a potential risk for malignancy. When necessary, genitoplasty was performed concomitantly. RESULTS: At the laparoscopic evaluation, 10 gonads of six patients were absent, while four were identified as 'vanishing'; 72 gonads (46 dysgenetic, 17 normal testes, one normal ovary, one ovotestis, seven gonadoblastomas or dysgerminomas) were removed; two ovotestes were replaced in the scrotum after removing the ovarian segment, as was one normal testis. Twelve patients with a urogenital sinus had its vaginal component removed, 11 including a hysterectomy. Three of these patients had a combined perineal approach to complete its removal, together with masculinizing genitoplasty. There were no intraoperative complications or conversions; two patients had complications after surgery. CONCLUSIONS: Laparoscopy allows the straightforward identification and removal of gonads. All abnormal ductal structures must be removed, as this increases the chance of resecting unidentified gonads. Removing the uterus and vaginal component of the urogenital sinus in patients with male social sex is feasible, with low morbidity. Genitoplasty, according to the social sex, can be performed in the same procedure.

Comprehensive surgical treatment of prune belly syndrome: 17 years' experience with 32 patients.

OBJECTIVES: To describe the results of comprehensive surgical management of prune belly syndrome. METHODS: Thirty-two patients were evaluated and treated for abdominal and genitourinary abnormalities. The surgical procedure, including simultaneous abdominoplasty, bilateral orchiopexy, and urinary tract reconstruction, was performed according to individual needs. At follow-up, the urinary tract, abdominal, and genital anatomy and function were evaluated. RESULTS: The upper urinary tract anatomy and function were stabilized in 30 patients, and no vesicoureteral reflux was found postoperatively. The bladder drainage was adequate in 29 patients, and 4 presented with recurrent bacteriuria. Abdominoplasty improved flaccidity in 29 patients. Adequate testicular position and consistency were obtained in 54 testes. Complications included acute tubular necrosis (1 patient) and ureterovesical obstruction (3 patients). CONCLUSIONS: Individualized comprehensive surgical management of prune belly syndrome is effective, with an acceptable incidence of complications and excellent long-term results.

Clinical, hormonal, behavioral, and genetic characteristics of androgen insensitivity syndrome in a Brazilian cohort: five novel mutations in the androgen receptor gene.

Androgen insensitivity syndrome (AIS) is caused by mutations in the androgen receptor gene and is associated with a variety of phenotypes in 46,XY individuals, ranging from phenotypic women [complete form (CAIS)] to men with minor degrees of undervirilization or infertility [partial form (PAIS)]. We studied 32 subjects with male pseudohermaphroditism from 20 families (9 CAIS, 11 PAIS) with the following criteria for AIS: 46,XY karyotype, normal male basal and human chorionic gonadotropin-stimulated levels of serum testosterone and steroid precursors, gynecomastia at puberty, and, in prepubertal patients, a family history suggestive of X-linked inheritance. The entire coding region of the androgen receptor gene was analyzed, and mutations were found in all families with CAIS and in eight of 11 families with PAIS. Fifteen different mutations were identified, including five (S119X, T602P, L768V, I898F, and P904V) that have not been described previously. Detailed clinical and hormonal features were compared with genotype in 25 subjects with AIS and confirmed by mutational analysis. LH hormone levels and the LH x testosterone product were high in all postpubertal subjects with AIS. All subjects with PAIS maintained at postpubertal age the gender identity and social sex that was assigned to them in infancy, in contrast to other forms of pseudohermaphroditism.

Tratamento da hiperplasia supra-renal congênita por deficiência da 21-hidroxilase / Treatment of congenital adrenal hyperplasia by 21-hydroxylase deficiency

O tratmento da hiperplasia supra-renal congênita por deficiência da 21-hidroxilase (HSRC-21 OH) tem como objetivos repor glico e mineralocorticóides, ecitar a virilizaçäo dos genitais externos, prevenir a desidratacao por perda de sal, controlar o hiperandrogenismo sem afetar a velocidade d crescimento, preservar a funçäo gonadal, fertilidade e estatura final. Relatamos a nossa experiência no acompanhamento de 96 pacientes com HSRC-21OH. nas crianças utilizamos como glicocorticóide o acetato de cortisona (18-20 mg/m2/dia) e nos adultos a dexametasona (0,25-0,75 mg/dia). quando necessário, a reposiçäo do mineralocorticóide foi feita com 9 alfa-fluor-hidrocortisona50-250µg/dia dependendo da faiza etária. Apesar da substiruiçäo adequadacom glico e/ou minerolocorticides o resultado final do tratamento da HSRC-21OH ainda deixa a desejar, principalmente em relaçäo ao crescimento, já que a estatura final na maior parte das caduísticas está entre -1 e -2 DP em relaçäo a estatura alvo. Novas terapêuticas da HSRC-21OH, como a associaçäo de hidrocortisona, fludocortisona , flutamida e tstolactona ou a supra rrenalectomia cirúrgica, ainda estäo em fase experimental e a evoluçäo a longo prazo é necessária para avaliar seu real efeito.

Cholelithiasis in cirrhotic patients (analysis of cholelithiasis among patients with liver cirrhosis in Säo Paulo, Brazil)

During the past 20 years, several authors have reported increased prevalence of cholelithiasis in liver cirrhosis. This biliary disease has been implicated with the deterioration of liver function, liver disease of alcoholic origin or even the presence of hypersplenism in this patient population. This study analyzes the incidence and possible factors which are responsible for promoting cholelithiasis in cirrhosis. The study included 110 cirrhotic patients of a private center specialized in treating liver diseases. The incidence of cholelithiasis was 27.3 per cent (25.3 per cent in males and 33.3 per cent in females). There was no correlation between liver function defined by Child's classification or through the laboratory examinations (AST, ALT, AP, GGT, PT, Alb, TB, DB, PA) and the presence of gallstones. No evidence was found that the etiology of cirrhosis or the presence/absence of hypersplenism affected the prevalence of cholelithiasis in this population. In conclusion, an increased prevalence of cholelithiasis was verified in this population of cirrhotics but the pathogenesis is still obscure.

Patogênese da retençäo de sódio em cirróticos / Pathogenesis of sodium retention in cirrhotics

Os cirróticos desenvolvem durante a evoluçäo natural da doença anormalidades na excreçäo de sódio. Mecanismos envolvidos na patogênese desse processo säo complexos e se caracterizam por reduzidos fluxo renal, pressäo de perfusäo e índice de filtraçäo glomerular, além de acentuadas anastomoses arteriovenosas. Ao mesmo tempo, hipotensäo arterial, débito e índice cardíacos elevados, com menor resistência vascular periférica, ocorrem. Na fase mais avançada, observa-se maior ativaçäo do sistema simpático, secreçäo aumentada de renina-angiotensina-aldosterona, além de substâncias vasoconstritoras, como leucotrienos, tromboxane e vasodilatadores, como prostaglandina, endotelina I, fator natriurético atrial e cininas. O caráter desses distúrbios hemodinâmicos, humorais e renais säo discutidos neste artigo

Complicaçöes neurológicas em cirróticos / Neurological complications in the cirrhotic patients

Alteraçöes histológicas do sistema nervoso central ocorrem em cirróticos, relacionados à gravidade da insuficiências hepática. As mais comumente observadas säo atrofia, edema, proliferaçäo de astrócitos protoplasmáticos tipo II (Alzheimer) degeneraçäo e perda de células nervosas, necrose laminar ou pseudolaminar do córtex cerebral e polimicrocavitaçäo da funçäo branco-cinzenta, descritas em pacientes que faleceram em coma hepático. Essas anormalidades se encontram associadas com encefalopatia hepática de manifestaçäo clínica ou evoluçäo subclínica (latente). Todos esses pacientes mostram distúrbios neuropsicológicos, correlacionados com medidas eletrofisiológicas, induzidos por fatores metabólicos, exteriorizáveis por ressonância magnética e tomografia cerebral computadorizada. Esses sinais neuroradiológicos säo reversíveis após transplante de fígado, fase em que outras alteraçöes neuropatológicas podem ser observadas. Essas, säo induzidas pelo uso de fármacos imunossupressores, tais como ciclosporina e FK-506. Outras complicaçöes nessa fase säo encefalopatia, crises, infartos cerebrais, hemorragia intracraniana, meningoencefalite, mielinólise pontina central e absessos. Tais aspectos säo comentados neste artigo