Podra Ud. Si el motociclista inicia su movimiento desde el reposo e incrementa su velocidad a razn constante. Cmo podra determinar su velocidad y aceleracin en la parte ms alta de su trayectoria. En un movimiento plano se utilizan las vectores unitarios u t y u n El origen se encuentra ubicado sobre la trayectoria de la partcula. La aceleracin ser Si la trayectoria es una recta, el vector sera constante en magnitud y direccin, por tanto Pero cuando la trayectoria es curva la direccin de cambia por lo tanto.
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The objective was to perform a systematic review of literature concerning epidemiology, clinical and biological data, prognosis and therapy of sarcomatoid renal cell carcinomas. Data on sarcomatoid renal cell carcinomas have been sought by querying the server Medline with MeSH terms following or combination of them: "renal carcinoma", "renal cell carcinoma," "renal cancer", " sarcomatoid " " sarcomatoid transformation" and " sarcomatoid differentiation. Twenty papers were selected.
The imaging was not specific for the diagnosis and biopsy had a low sensitivity for identifying a sarcomatoid contingent. The treatment was based on a combination of maximal surgical resection whenever possible and systemic therapy for metastastic disease. Pathological data often showed large tumors, Furhman 4 grades, combined biphasic carcinomatous contingent clear cell carcinoma in most cases and sarcomatoid. Genetically, there was no specific abnormality but a complex association of chromosomal additions and deletions.
The prognosis was pejorative with a specific median survival of 5 to 19 months without any impact of the sarcomatoid contingent rate. Sarcomatoid renal cell carcinoma is a form not to ignore despite its rarity. Mainly symptomatic and discovered at an advanced stage, it has a poor prognosis, requiring multidisciplinary management quickly and correctly.
All rights reserved. Pulmonary sarcomatoid carcinomas are a rare group of tumors accounting for about one percent of non-small cell lung carcinoma NSCLC.
In , the World Health Organization classification united under this name all the carcinomas with sarcomatous-like component with spindle cell or giant cell appearance, or associated with a sarcomatous component sometimes heterologous. There are five subtypes: pleomorphic carcinoma, spindle cell carcinoma, giant cell carcinoma, carcinosarcoma and pulmonary blastoma. Epithelial to mesenchymal transition pathway may play a key role. Patients, usually tobacco smokers, are frequently symptomatic.
Distant metastases are frequent with atypical visceral locations. These tumors have poorer prognosis than the other NSCLC subtypes because of great aggressivity, and frequent chemoresistance.
Here we present pathological description and a review of literature with molecular features in order to better describe these tumors and perhaps introduce new therapeutics.
MUC4, a novel immunohistochemical marker identified by gene expression profiling, differentiates pleural sarcomatoid mesothelioma from lung sarcomatoid carcinoma. Sarcomatoid mesothelioma, a histological subtype of malignant pleural mesothelioma, is a very aggressive tumor with a poor prognosis. Histological diagnosis of sarcomatoid mesothelioma largely depends on the histomorphological feature of spindled tumor cells with immunohistochemical reactivity to cytokeratins.
Although there are promising immunohistochemical antibody panels to differentiate mesothelioma from lung carcinoma, a consensus on the immunohistochemical markers that distinguish sarcomatoid mesothelioma from lung sarcomatoid carcinoma has not been reached and requires further study. We performed whole gene expression analysis of formalin-fixed paraffin-embedded tissue from sarcomatoid mesothelioma and lung sarcomatoid carcinoma and observed significant differences in the expression of MUC4 and other genes between sarcomatoid mesothelioma and lung sarcomatoid carcinoma.
Therefore, we recommend to include MUC4 as a novel and useful negative immunohistochemical marker for differentiating sarcomatoid mesothelioma from lung sarcomatoid carcinoma. A histological challenge? As it has both epithelial and mesenchymal components, there are many theories concerning its origin and it can prove a diagnostic challenge.
A 76 year old male smoker presented with dysphonia. Vocal cord injury was found on examination but no lymphadenopathy or metastases were present. Laryngeal microsurgery was performed with complete excision of the lesion. Histopathology showed it to be a carcinosarcoma which showed intense and diffuse positivity for vimentin and focal positivity for AE1-AE3, CK5 and p The patient underwent radiotherapy as complementary treatment. Sarcomatoid carcinoma usually presents with obstructive symptoms such as dysphonia.
Prognosis depends on the stage and the presence or not of metastases. Both epithelial markers EMA, cytokeratin AE1-AE3 , epithelial membrane antigen, Ki 67 and mesenchymal markers such as vimentin, desmin, S may be positive in these tumours. Recommended treatment for T2-T1 stages is an excisional biopsy which can be followed by adjuvant radiotherapy; radiotherapy alone has also been successful.
T3-T4 stages can be treated with local excision, partial laryngectomy or total laryngectomy with subsequent ganglion emptying and concomitant radio and chemotherapy. Pulmonary sarcomatoid carcinoma: University of Cincinnati experience. PubMed Central. Results There was no significant difference in survival of patients treated with chemotherapy alone median, days compared to patients not undergoing treatment median, Patients who underwent surgery and adjuvant chemotherapy showed a trend in improvement of survival median, Patients requiring only surgery had the longest OS of Conclusions Systemic chemotherapy alone did not improve survival in patients with PSC.
Surgery provides the greatest overall survival benefit and adjuvant chemotherapy may also improve survival. The outcomes were retrospectively analyzed by treatment with overall survival OS as the endpoint. Sarcomatoid carcinoma SARC of the lung is a very rare and aggressive type of nonsmall cell lung cancer.
It belongs to a group of poorly differentiated carcinomas with partial sarcomatoid differentiation or with a direct sarcoma component. Characteristic findings include a large tumor with an invasive tendency, early recurrence and systemic metastases. The authors present a case of SARC in the year-old patient. Histological findings confirmed the dia-gnosis of sarcomatoid pleomorphic carcinoma pT3N0M0. The patient underwent adjuvant chemotherapy; recurrence and systemic dissemination of the disease occurred after 20 months; the patient died 21 months after the surgery.
Sarcomatoid renal cell carcinoma: Biology and treatment advances. Sarcomatoid transformation in renal cell carcinoma, so called sacromatoid RCC sRCC , is associated with an aggressive behavior and a poor prognosis. Current therapeutic approaches are largely ineffective. Recent studies looking into the genomic and molecular characterization of sRCCs have provided insights into the biology and pathogenesis of this entity. These advances in molecular signatures may help development of effective treatment strategies.
We herein present a review of recent developments in the pathology, biology, and treatment modalities in sRCC. Sarcomatoid carcinoma associated with small cell carcinoma of the urinary bladder: a series of 28 cases.
The association of sarcomatoid carcinoma SC with small cell carcinoma SCC has not been systematically studied. We identified 39 consult cases between and with available slides for review in 28 cases. There were 19 men and 9 women mean age: 78 years . In 26 Mortality did not differ based on pathological groups. The month actuarial risk of death was The multitude of different components in these tumors is further evidence of the remarkable ability of carcinoma of the bladder to show divergent differentiation with, in some cases, gradual transition between SCC and other elements including sarcomatoid.
Greater recognition of this entity with chemotherapy targeted to the various histological elements may have important therapeutic implications.
Mixed papillary- sarcomatoid carcinoma of the penis: report of an aggressive subtype. Several different histological subtypes of penile carcinoma had been described in the last decades, many with different biological behavior and prognosis. The association of two histological subtypes mixed tumors can be observed in one third of the cases. The most common association is of warty and basaloid tumors, two HPV-related carcinomas. Here, we described a mixed papillary- sarcomatoid carcinoma, never reported before.
Although it is a clinical aspect of a low-grade verruciform tumor, its prognosis showed it to be very aggressive due to the sarcomatoid component hidden above the papillary component. High-dose interleukin 2 in patients with metastatic renal cell carcinoma with sarcomatoid features. We report a single institution experience with 21 patients with mRCC with sarcomatoid features post-nephrectomy who were treated with HD IL Baseline patient characteristics, HD IL-2 cycles, time to progression, and subsequent therapies were evaluated.
Results Patients were predominantly Caucasian males with a median age of 54 years. Number of HD IL-2 doses did not correlate with response with a mean of Median OS was Within the subset of patients who had progression on IL-2, median OS was In patients who received second-line therapy, median PFS was 7. Disease characteristics were evaluated for significance using the Fischer's exact test and Wilcoxon rank sum test. Patients were predominantly Caucasian males with a median age of 54 years.
Epidemiology, biology and treatment of sarcomatoid RCC: current state of the art. Long recognized to confer an extremely poor prognosis, sarcomatoid dedifferentiation of renal cell carcinoma sRCC is a tumor phenotype that is finally beginning to be better understood on the molecular and genetic levels. The main reasons for its poor outcome include its aggressive biology, its tendency to present at an advanced or metastatic stage at the time of diagnosis, its high rate of tumor recurrence after nephrectomy, and its limited response to systemic therapies.
Molecular pathology studies suggest that sarcomatoid dedifferentiation originates from a focal epithelial-mesenchymal transition EMT arising in the carcinomatous component of the tumor. It is hoped that the growing understanding of the molecular biology of sRCC will soon make it possible to adapt treatments based on the identification of actionable tumor alterations.
The deliberate inclusion of these patients in the multicenter clinical trials of immune, targeted and combination therapies is a necessary next step in pioneering future treatment strategies. Sarcomatoid carcinoma of the adrenal gland: A case report and review of literature. Reports about adrenocortical carcinomas AC mixed with sarcomatous areas are very rare.
The terminology and pathogenesis of such biphasic tumors remain controversial. Herein, we report a case of sarcomatoid carcinoma of the adrenal gland in a year-old woman who presented with left abdominal pain of one month's standing.
The results of abdominal ultrasonography and computed tomography CT showed the presence of a large heterogeneous adrenal mass.
A left adrenalectomy and complete splenectomy were performed. Histologically, the neoplasm showed areas of adrenocortical carcinoma and areas of sarcomatoid spindle cell proliferation. When examined immunohistochemically, the carcinomatous cells stained positively for S protein, Melan-A protein, and neuron-specific enolase NSE , and focally for vimentin and the cytokeratin marker MNF Also, the carcinomatous cells were immunoreactive to the monoclonal antibody HMB The sarcomatous component expressed vimentin, as well as other smooth and skeletal muscle markers.
Liver metastases appeared 3 months postoperatively.
Semana 14 Estatica Dinamica Componentes Tangencial y Normal
Es necesario analizar las fuerzas involucradas. Por ejemplo, se redujo la conicidad de las bandas de rodadura de las ruedas del Shinkansen de 0,40 a 0,16 para lograr estabilidad a altas velocidades, compatible con un rendimiento aceptable en las curvas. Un primer error habitual es suponer de que las ruedas son redondas. El deslizamiento es la velocidad adicional que tiene la rueda respecto a la locomotora, y la fluencia es el deslizamiento dividido por la velocidad de la locomotora.