[Primary pulmonary rabdomyosarcoma: clinical-pathological and immunohistochemical findings]

Pulmonary rhabdomyosarcona is a rare entity and the histopatological differential diagnosis can be difficult. We report on a case of a 48-year-old male patient with a neoplasm located at the hilum of the right lung. The histological study of the lobectomy specimen allowed the diagnosis of embryonal rhabdomyosarcoma to be made. Given the absence of tumor lesions in other sites, it was classified as primary pulmonary neoplasm. The patient underwent chemotherapy and subsequently a completion pneumonectomy for recurrence of the tumor. One year after the initial surgery, he presented a metastasis in the right adrenal gland. He died 20 months after the original diagnosis. The importance of immunohistochemistry in the diagnosis is emphasized and the different theories that attempt to explain the histogénesis of these tumors in unusual sites are analyzed.

Use of three-dimensional computational fluid dynamics model for a new configuration of circular primary settling tank

Appropriately used, computational fluid dynamics models are powerful tools to design and optimize primary settling tanks (PSTs). This paper uses a Fluent-based 3D model to identify the possible causes for underperformance of the circular PSTs at the Cali waste-water treatment plant, Colombia, and to propose design modifications to improve performance. A new configuration for the center well (CW) is proposed and evaluated. The influence of a rotational sludge scraper and of continuous sludge removal were considered in the numerical simulation. The new configuration included the modification of the current CW diameter and the location of a second baffle with the CW. The results suggest that the installation of the second baffle allows a more uniform flow distribution within the PST and consequently, the hydrodynamic problems associated with short-circuiting of the influent to the bottom of the tank are reduced. The second baffle suppresses the downward current, effectively dissipates the kinetic energy in the influent and forces the particles to move toward the bottom of the PST. In addition, the second CW baffle allows the formation in the inlet zone of a consistently more concentrated sludge blanket layer and thicker sludge, reducing the risk of solids leaving in the effluent of the PST.

Fosfomycin prevents cisplatin-induced ototoxicity: Results of a randomized, double blind, placebo controlled trial

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Background: Cisplatin is one of the most frequently used chemotherapy agents. The main dose-limiting toxicity for its use is hearing-loss, present in 40–100% of patients. To date, no treatment has proven efficacy in preventing or reducing cisplatin acoustic damage. Fosfomycin, acting as a free-radical scavanger, has shown to reduce cisplatin-induced ototoxicity and nephrotoxicity in animal models, without affecting its antineoplastic activity. This trial evaluated the effect of fosfomycin in cisplatin-induced ototoxicity. Methods: 22 chemotherapy naive patients with normal audition, scheduled to receive cisplatin-based chemotherapy (cumulative dose =200mg/m2) were randomized to receive placebo (n=11) or 1g of IV fosfomycin concurrent with each cisplatin administration (2–4 cycles). Primary outcome was ototoxicity when comparing audiometric studies (low and high frequencies and otoaccustic emissions) at baseline and at completion of chemotherapy. With β=0.8 and a=0.05 the study was powered to detect differences =20 dB at any given frequency. Fisher's test, Wilcoxon and Mann-Whitney test were used. Results: Groups were balanced for baseline characteristics, cisplatin dose and response rates. No differences were found when comparing ototoxicity at low frequency ranges. When analyzing high frequencies and otoaccustic emissions, 9 patients (82%) in the placebo group developed ototoxicity vs 4 (36%) in the fosfomycin group (p=0.04). The degree of hearing-loss, evaluated by comparing percentage of change in each evaluated frequency, was significantly lower in patients receiving fosfomycin (p=0.04). Other chemotherapy toxicities were similar in both groups. Conclusions: In patients with audiometric integrity, the concurrent administration of fosfomycin with cisplatin significantly reduces ototoxicity. The degree of hearing-loss is lower in patients receiving fosfomycin than in those receiving placebo. The use of fosfomycin in combination with cisplatin is safe and does not interfere with its antineoplastic activity. To our knowledge this is the first clinical-trial that demonstrates prevention and reduction of cisplatin-induced hearing-loss.

No significant financial relationships to disclose.

[Evaluation by two-dimensional and doppler echocardiography of the results of percutaneous mitral valvuloplasty]

The purpose of this study was to determine the value of two-dimensional echocardiography and doppler ultrasound in the evaluation of the results and mechanism of percutaneous mitral valvuloplasty. The study involved 200 patients (77 p. 100 female) of mean age 43 +/- 15 years (range 13 to 79 years), most of whom were in NYHA class III or IV. The patients were divided into three groups according to the severity of the anatomical lesions. Group I patients (n = 58) had flexible valves and only minor alterations of the subvalvular structures; group II patients (n = 75) had flexible valves but deeply altered subvalvular structures; group III patients (n = 67) had calcified valves. Following valvuloplasty, the mean transmitral doppler gradient fell from 16 to 5 mmHg (p less than 0.0001) and the mitral valve area, as measured by two-dimensional echocardiography, increased from 1 to 1.9 cm2 (p less than 0.00001); the corresponding values at doppler measurement were 1 and 2 cm2 respectively. In patients successfully dilated, two-dimensional echocardiography showed that the mechanism involved was complete opening of one or both commissures. Before dilatation, 68 patients (34 p. 100) had an usually small degree of mitral regurgitation. After dilatation, grade 3/4 mitral regurgitation was observed in 9 patients (4.5 p. 100). The quality of the results obtained depended on the anatomical lesions.(ABSTRACT TRUNCATED AT 250 WORDS)