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1.
Materials (Basel) ; 15(17)2022 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-36079388

RESUMO

Materials used in the marine industry are exposed to extreme conditions, so it is necessary to meet remarkable characteristics, such as mechanical resistance, low density, and good corrosion resistance. The challenging environment requires continuous performance improvements, so this work is focused on developing new materials with superior properties, using the electrochemical deposition technique, which are convenient for marine engineering. High-entropy alloys have been attracting tremendous interest in many applications, due to their simple crystal structures and advantageous physical-chemical properties, such as high strength, anti-corrosion, erosion, and electro-magnetic capabilities. To identify the most appropriate compositions, MatCalc software was used to predict the structure and characteristics of the required materials, and thermodynamic and kinetic criteria calculations were performed. The modelling processes generated a series of optimal compositions in the AlCrCuFeNi alloy system, that are suitable to be used in anticorrosive and tribological applications. The composition and morphology of the obtained high entropy alloy thin films revealed a uniform structure, with a small grain profile. The corrosion resistance was investigated in artificial seawater to observe the behavior of the newly developed materials in demanding conditions, and the results showed improved results compared to the copper foil substrate.

2.
Rom J Morphol Embryol ; 57(3): 1045-1050, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28002522

RESUMO

INTRODUCTION: Retroperitoneal seminoma is a very rare form of cancer, with embryological origin represented by primordial germ cells from the urogenital ridges left behind during the fetal development. Extragenital germ cell tumors can also occur in the mediastinum or the pineal gland. The aim of this paper is to outline the particularities and draw embryological, histopatological and treatment conclusions regarding extragonadal germ cell tumors. PATIENT AND METHODS: A 43-year-old patient without any additional pathology was admitted for anemia of unknown etiology. The clinical examination revealed through deep abdominal palpation a mass in the left flank, and normal testes. Thoraco-abdomino-pelvic computed tomography (CT) scan showed a large retroperitoneal tumor adjacent to the great vessels in the left lumbo-iliac region. The blood work revealed just a low hemoglobin and hematocrit. With the established diagnosis of retroperitoneal tumor, radical surgical removal was decided. During the surgery, we were required to dissect a large solid encapsulated tumor mass from the aorta and the common iliac artery, starting at the renal pedicle all the way to the left iliac bifurcation. The surgical access was obtained through a transperitoneal left subcostal incision prolonged pararectally. Histopathological and immunohistochemical studies revealed a seminoma of the usual type. After the histological findings, the patient's tumor markers were investigated (LDH - lactate dehydrogenase, ßHCG - beta-human chorionic gonadotropin, αFP - alpha-fetoprotein), all values being within normal ranges. In addition, the left testicle was thoroughly reexamined, clinically, through ultrasound and magnetic resonance imaging (MRI) scans, and no abnormalities were observed. After the surgery, the patient followed three courses of chemotherapy (BEP - Bleomycin, Etoposide and Cisplatin). RESULTS: The CT scan done 24 months after surgery found no signs of local or distant tumor recurrence. The patient entered a follow-up schedule consisting of periodical clinical, serological and imagistic evaluations. CONCLUSIONS: Primary retroperitoneal seminoma is a rare entity that must be taken into account when treating a retroperitoneal tumor. It develops out of the urogenital ridge, while the testes are normal. Thorough testicular evaluation (clinical, ultrasound and serum markers) is mandatory in all retroperitoneal tumors. The histopathological analysis is crucial for an accurate diagnosis and a proper management strategy. Through radical surgery and chemotherapy, the patients that are diagnosed prior to massive visceral metastatic dissemination can be cured.


Assuntos
Neoplasias Retroperitoneais , Neoplasias Testiculares , Adulto , Humanos , Masculino , Neoplasias Retroperitoneais/embriologia , Neoplasias Retroperitoneais/patologia , Neoplasias Retroperitoneais/terapia , Seminoma/embriologia , Seminoma/patologia , Seminoma/terapia , Neoplasias Testiculares/embriologia , Neoplasias Testiculares/patologia , Neoplasias Testiculares/terapia
3.
Springerplus ; 5(1): 1284, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27547659

RESUMO

BACKGROUND: JJ stents are often encountered in patients with pelvic renal stones referred for shock wave lithotripsy, most of them being placed either for obstructive renal pelvic stones or for ureteric stones mobilized retrograde during the JJ stent insertion. The aim of the study was to determine whether the relative stone position in the upper loop of the JJ stent during extracorporeal shock wave lithotripsy (SWL) influences the efficiency of the procedure. The study was designed as a prospective cohort study on 162 patients addressing the same urological department, with single renal pelvic stone (primary or mobilized to the renal pelvis during the insertion of JJ stent), smaller than 15 mm, with JJ stent, treated by SWL using a second generation spark gap lithotripter, 18 kV, 3000 waves/session. Patients were divided in three groups according to the relative position of the stone to the upper loop of the JJ stent as appears on plain X-ray: stone-inside-loop, loop-crossing-stone and stone-outside the loop. The SWL success rate was the primary outcome of the study. p Value, Chi square and Kruskal-Wallis tests were used for statistical analysis. RESULTS: For stone-inside-loop cases, SWL efficiency was 22.7 versus 42 % for all the other cases (p = 0.002). Other factors for decreased SWL success rate were: higher stone radio-opacity, larger JJ of stent and obese patients. Study limitation is represented by the relative small study group and by the evaluation of stone density using plain X-ray instead of computer tomography. CONCLUSIONS: For pelvic renal stones having the same density characteristics studied by plain X-ray, the SWL efficiency is lower in stone-inside-loop cases comparing with the other positions. The overall stone free rate for renal pelvic stones could be explained by the second generation lithotripter used for all procedures.

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