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1.
Environ Pollut ; 265(Pt A): 114950, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32554092

RESUMEN

Liquid hydrocarbon pipeline accidents, including leaks due to the illegal or unauthorized collection of petroleum from oil pipelines, are a widespread phenomenon that can lead to pollution that may negatively affect soil quality and plant growth. The aim of this study is to evaluate hydrocarbon uptake and accumulation in Zea mays plants grown on soil affected by spills of fossil fuels. The experiments were conducted in microcosm, mesocosm and field tests. The potential transfer of contaminants from soil to plant and their effects on plant growth were investigated. The results from both the laboratory and field experiments showed that the plants grew better in the uncontaminated soil than in the soil polluted by hydrocarbons. Despite their significantly lower aerial biomass, plants grown in contaminated soil did not show any significant differences in C > 12 concentration, either in shoots or roots, compared to the control plants. Thus, the decrease in plant yield might not be attributed to hydrocarbons accumulation in the plant tissues and may rather be due to a reduced soil fertility, which negatively affected plant growth. Under our experimental conditions, the hydrocarbons present in the contaminated soil were not absorbed by the plants and did not accumulate in plant tissue or in grains, thus avoiding the risk of them entering the food chain.


Asunto(s)
Petróleo , Contaminantes del Suelo/análisis , Biodegradación Ambiental , Hidrocarburos , Suelo , Zea mays
2.
Am J Otolaryngol ; 36(4): 547-53, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25749259

RESUMEN

PURPOSE: Esthesioneuroblastoma is an uncommon malignancy of the head and neck for which there is no defined treatment protocol. The purpose of this study is to report our experience with the treatment and patterns of failure of this disease. METHODS AND MATERIALS: From 1994 to 2012, 37 previously unreported patients with esthesioneuroblastoma were evaluated, and 32 eventually treated for cure at 2 academic medical centers. All patients were staged with Kadish criteria. The mean and median follow-ups were 96.1 and 76.5 months respectively (range 6-240 months). RESULTS: The Kadish stage was A in 6 patients, B in 13 patients, and C in 13 patients. Four patients were initially treated with concurrent chemo-radiation therapy. Twenty-eight patients were treated with primary surgery. Two (2) underwent open medial maxillectomy and 26 underwent craniofacial resection (open - 17, endoscopic - 9). Three patients received curative surgical resection only. Seven patients failed either within the cranial axis or distantly, 6 of the 7 are dead of disease, 10-194 months following initial treatment. Six patients had isolated neck recurrences, 4/6 were salvaged with neck dissection and additional chemo-radiation and remain alive 30-194 months following initial treatment. Estimated overall survival rate at 10 years was 78% based on Kadish and T stages. CONCLUSION: In this retrospective analysis of 32 patients, Kadish stage C and stage T3/T4 tumors were associated with worse outcome. Total radiation dose of 60 Gy, margin status, patient age, were not found to have significant prognostic value.


Asunto(s)
Estesioneuroblastoma Olfatorio/terapia , Cavidad Nasal , Recurrencia Local de Neoplasia/terapia , Neoplasias Nasales/terapia , Adulto , Anciano , Anciano de 80 o más Años , Terapia Combinada , Supervivencia sin Enfermedad , Estesioneuroblastoma Olfatorio/diagnóstico , Estesioneuroblastoma Olfatorio/mortalidad , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/mortalidad , Estadificación de Neoplasias , Neoplasias Nasales/diagnóstico , Neoplasias Nasales/mortalidad , Pronóstico , Estudios Retrospectivos , Tasa de Supervivencia/tendencias , Insuficiencia del Tratamiento , Estados Unidos/epidemiología
3.
J Neurol Surg Rep ; 75(1): e175-9, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25083380

RESUMEN

Giant cell tumors (GCTs) are rare, usually affecting the epiphyses in long bones of the extremities. They seldom occur in the skull, where they preferentially affect the sphenoid and temporal bones. Considered to be benign, locally aggressive lesions, they may cause cranial nerve deficits by compression but infrequently invade the dura and parenchyma of the brain. Several case reports with follow-up describe gross total resection of skull base GCT to be curative. Anything short of total resection usually results in recurrence within 4 years. Radiation therapy, although controversial, is reserved for lesions that cannot be completely resected. Some argue, however, against the use of radiation because there are reported cases of malignant transformation. Here we describe the case of a large GCT that was invasive to the dura, temporal lobe, as well as the third division of the trigeminal nerve, and to date gross total resection has been curative of this lesion. The patient has not undergone radiation therapy.

4.
J Hazard Mater ; 231-232: 36-42, 2012 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-22771350

RESUMEN

Mercury-contaminated soils from a petrochemical plant in southern Italy were investigated to assess the phytoextraction efficiency of crop plants treated with the phytohormone, cytokinine (CK foliar treatment), and with the thioligand, ammonium thiosulfate (TS, soil application). Plant biomass, evapotranspiration, Hg uptake and distribution in plant tissues following treatment were compared. Results indicate the effectiveness of CK in increasing plant biomass and the evapotranspiration rate while TS treatment promoted soil Hg solubility and availability. The simultaneous addition of CK and TS treatments increased Hg uptake and translocation in both tested plants with up to 248 and 232% in Brassica juncea (Indian mustard) and Helianthus annuus (sunflower) respectively. B. juncea was more effective in Hg uptake, whereas H. annuus gave better response regarding plant biomass production. The effectiveness of the treatments was confirmed by the calculation of Hg phytoextraction and evaluation of labile-Hg residue in the soil after plant growth. In one growing cycle the plants subject to simultaneous CK and TS treatment significantly reduced labile-Hg pools that were characterized by the soil sequential extraction, but did not significantly affect the pseudototal metal content in the soil. Results support the use of plant growth regulators in the assisted phytoextraction process for Hg-contaminated soils.


Asunto(s)
Brassica/metabolismo , Citocininas/farmacología , Helianthus/metabolismo , Mercurio/metabolismo , Reguladores del Crecimiento de las Plantas/farmacología , Tiosulfatos/farmacología , Biodegradación Ambiental , Brassica/efectos de los fármacos , Industria Química , Helianthus/efectos de los fármacos , Residuos Industriales , Transpiración de Plantas , Contaminantes del Suelo/metabolismo
5.
Int J Phytoremediation ; 13(1): 1-17, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21598764

RESUMEN

The influence of repeated applications of tartrate (TAR) and glutamate (GLU) at 50-mmol kg(-1) of soil on Cd, Cu, Pb, and Zn distribution between a contaminated soil and Paulownia tomentosa was investigated. TAR and GLU were applied by a single or a double dosage, the latter carried out with an interval between the two applications of thirty days. The comparison of the differences in mean amounts of metals accumulated in the whole plant at the end of single and double TAR and GLU application experiments indicated the positive effect of repeated GLU applications on the accumulation of Cu, Pb, and Zn by Paulownia tomentosa as compared to untreated controls. A similar effect was not observed for the TAR treatments. When soil treated with either TAR or GLU was compared with untreated controls, no significant effect on heavy-metal concentrations in the soil solution was observed 30 days after treatment, suggesting the absence of an increase of the long-term leaching risk of heavy metals in aquifers and surface waters due to the ligand application. A cost analysis of the treatment is also reported.


Asunto(s)
Biodegradación Ambiental , Ácido Glutámico/farmacología , Magnoliopsida/metabolismo , Metales Pesados/metabolismo , Tartratos/farmacología , Transporte Biológico/efectos de los fármacos , Cadmio/análisis , Cadmio/metabolismo , Cobre/análisis , Cobre/metabolismo , Plomo/análisis , Plomo/metabolismo , Magnoliopsida/efectos de los fármacos , Metales Pesados/análisis , Suelo/análisis , Contaminantes del Suelo/análisis , Contaminantes del Suelo/metabolismo , Zinc/análisis , Zinc/metabolismo
6.
Chemosphere ; 75(6): 808-14, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19217142

RESUMEN

In microcosm experiments, the use of inorganic and organic amendments has been studied as potential agents to reduce heavy metal bioavailability in an acidic soil highly contaminated by Cu, Zn and Ni, that has to be remediated by phytoremediation. The concentrations of heavy metals in the original soil (O-Soil) produced phytotoxic effects with a strong reduction in biomass yield that hinder the utilization of this technology. To overcome phytotoxicity the use of three immobilizing agents was evaluated. The results obtained showed that all the strategies decreased the mobile fractions of heavy metals in soil and increased the metal removal efficiency. In the case of Brassica juncea the best results for Zn and Ni were obtained after zeolites addition (Z-Soil) with an increase of about 6 times with respect to the value found in the O-Soil. In the case of Cu, the more efficient treatment was Ca(OH)(2) addition (Ca-Soil). The B. juncea plants accumulated Cu amounts 8 times greater than in the O-Soil. For this metal, relevant results were obtained also with compost, that increased the amount of Cu in the plants of 7 times with respect to the O-Soil. Similar results were obtained with Helianthus annuus the highest Zn and Ni accumulation was detected in the Z-Soil and compost-treated soils (C-Soil), with an increase of nearly 11 times with respect to the accumulation in the O-Soil. In the case of Cu the highest increase of total uptake was found in the C-Soil: 28 times higher than in the O-Soil. Total accumulation in Poa annua plants showed the highest removal efficiency in the Z-Soil for all metals. The values obtained increased of 4, 11 and 12 times for Cu, Zn and Ni, respectively.


Asunto(s)
Biodegradación Ambiental , Metales Pesados/metabolismo , Contaminantes del Suelo/metabolismo , Cobre/metabolismo , Helianthus/metabolismo , Planta de la Mostaza/metabolismo , Níquel/metabolismo , Poa/metabolismo , Zinc/metabolismo
7.
Chemosphere ; 72(10): 1481-1490, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18558420

RESUMEN

The distribution of Cd, Cu, Pb and Zn between a contaminated soil and the tree species Paulownia tomentosa was investigated in a pilot-scale assisted phytoremediation study. The influence of the addition of EDTA, tartrate and glutamate at 1, 5 and 10mM concentrations on metal accumulation by the plant and on metal mobilization in soil was evaluated. Root/shoot metal concentration ratios were in the range of 3-5 for Zn, 7-17 for Cu, 9-18 for Cd and 11-39 for Pb, depending on the type and concentration of complexing agent. A significant enhancement of metal uptake in response to complexing agent application was mainly obtained in roots for Pb (i.e. 359 mg kg(-1) for EDTA 10mM and 128 mg kg(-1) for the control), Cu (i.e. 594 mg kg(-1) for glutamate 10mM and 146 mg kg(-1) for the control) and, with the exception of glutamate, also for Zn (i.e. 670 mg kg(-1) for tartrate 10mM and 237 mg kg(-1) for the control). Despite its higher metal mobilization capacity, EDTA produced a metal accumulation in plants quite similar to those obtained with tartrate and glutamate. Consequently the concentration gradient between soil pore water and plant tissues does not seem to be the predominant mechanism for metal accumulation in Paulownia tomentosa and a role of the plant should be invoked in the selection of the chemical species taken up. Metal bioavailability in soil at the end of the experiment was higher in the trials treated with EDTA than in those treated with tartrate and glutamate, the latter not being significantly different from the control. These findings indicated the persistence of a leaching risk associated to the use of this chelator, while an increase of the environmental impact is not expected when glutamate and tartrate are applied.


Asunto(s)
Magnoliopsida/metabolismo , Metales Pesados/metabolismo , Contaminantes del Suelo/metabolismo , Biodegradación Ambiental/efectos de los fármacos , Cobre/metabolismo , Ecosistema , Ácido Edético/farmacología , Ácido Glutámico/farmacología , Tartratos/farmacología , Zinc/metabolismo
8.
Chemosphere ; 67(2): 322-9, 2007 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17107704

RESUMEN

Several organic compounds of high molecular weight present in soil interact with selenium and may act as active binding agents affecting its availability in soil, and, consequently, selenium uptake by plants. This study is aimed at investigating the effects of polysaccharides on selenium speciation in soil and on selenium absorption by Lactuca sativa L. plants. Three-week-old seedlings were transplanted into pots filled with soil, and sodium selenite at rates of 1.5 and 5mgSekg(-1) of soil, or sodium selenate at a rate of 1.5mgSekg(-1) of soil were applied. Carboxymethylcellulose (CMC) was added to the soil at rates of 0, 3 and 30mgkg(-1) of soil. After 48 and 110d from transplanting plants were harvested, separated into root and shoot, and fresh and dry matter weights were recorded. Total selenium was determined in both soil and plant samples. A sequential extraction was used to investigate the different Se oxidation states and assess the availability of Se in soil after the final harvesting. Both selenite and selenate were absorbed by roots, but plants amended with Se(VI+) showed higher selenium concentration than plants amended with Se(IV+). Selenite appears to be less mobile than selenate both in soil and plants. The addition of carboxymethylcellulose to soil decreased the amount of selenium absorbed by plants. CMC interacted with Se, making it less mobile as evidenced by the increase in the insoluble fractions. The insoluble Se forms in soil may represent environmental Se sinks potentially available for plants if the substrate is re-used for subsequent growth cycles and selenium species are mobilized as a result of biological and chemical processes.


Asunto(s)
Carboximetilcelulosa de Sodio/farmacología , Lactuca/metabolismo , Selenio/metabolismo , Lactuca/efectos de los fármacos , Raíces de Plantas/metabolismo , Brotes de la Planta/metabolismo , Ácido Selénico , Compuestos de Selenio/metabolismo , Selenito de Sodio/metabolismo
9.
Chemosphere ; 57(9): 1039-46, 2004 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15504462

RESUMEN

A treatability test of phytostabilization was carried out on two soils sampled downstream a mining Italian area with Lolium italicum and Festuca arundinacea. Beside chemical content of Pb and Zn in aerial parts and in roots, also some physical parameters were determined at the end of the growth cycle of plants. Particle size distribution was analysed with a laser granulometer while cracking patterns and porosity were determined by means of image analysis. Compost, used at two rates (10%, and 30% v/v) in order to improve soil physical characteristics, always raised biomass with similar effects for both doses. The concentration of Pb and Zn in aerial parts and in roots of L. italicum and F. arundinacea decreased more than five times in presence of compost. A general lack of clear effects of both plants on soil physical parameters was noticed. Formation of more water stable aggregates, a rise of the area occupied by cracks, and new porosity formed by elongated and irregular pores were found in soil samples treated with compost.


Asunto(s)
Festuca/metabolismo , Plomo/farmacocinética , Lolium/metabolismo , Contaminantes del Suelo/análisis , Zinc/farmacocinética , Biomasa , Italia , Tamaño de la Partícula , Suelo/análisis
11.
Otolaryngol Head Neck Surg ; 125(6): 640-4, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11743468

RESUMEN

OBJECTIVE: The purpose of this article is to review the clinicoradiographic features of lower cranial nerve sheath tumors and to outline surgical approaches that allow the safe and complete resection of these lesions. METHODS: Thirteen patients with lower cranial nerve sheath tumors of the infratemporal fossa were surgically treated between 7/88 and 10/99. A retrospective chart analysis provided details pertaining to clinical manifestations, radiographic assessment, intraoperative findings, tumor histology, and postoperative results. RESULTS: The most common presenting symptoms were neck pressure and voice change while submucosal palatal fullness and vocal cord paralysis were the most common presenting signs. All tumors were removed via lateral skull base approaches and the most common postoperative sequelae was dysphasia. CONCLUSION: Lower cranial nerve sheath tumors of the infratemporal fossa usually reach considerable size before diagnosis because of a naturally slow growth rate in this relatively silent location. The safe surgical removal of these tumors, based on superior control of the internal carotid artery, can be achieved through the use of contemporary lateral skull base techniques.


Asunto(s)
Neoplasias de los Nervios Craneales/diagnóstico , Neoplasias de los Nervios Craneales/cirugía , Nervio Glosofaríngeo , Neoplasias de Cabeza y Cuello/diagnóstico , Neoplasias de Cabeza y Cuello/cirugía , Nervio Hipogloso , Neurilemoma/diagnóstico , Neurilemoma/cirugía , Neoplasias de la Base del Cráneo/diagnóstico , Neoplasias de la Base del Cráneo/cirugía , Adulto , Angiografía , Afasia/etiología , Biopsia , Traumatismos de las Arterias Carótidas/etiología , Neoplasias de los Nervios Craneales/complicaciones , Nervios Craneales , Femenino , Neoplasias de Cabeza y Cuello/complicaciones , Hematoma/etiología , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Neurilemoma/complicaciones , Dolor/etiología , Complicaciones Posoperatorias/etiología , Estudios Retrospectivos , Neoplasias de la Base del Cráneo/complicaciones , Tomografía Computarizada por Rayos X , Resultado del Tratamiento , Parálisis de los Pliegues Vocales/etiología
12.
Cancer ; 92(9): 2334-40, 2001 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-11745288

RESUMEN

BACKGROUND: Two-thirds of patients with squamous cell carcinomas of the head and neck (SCCHN) at diagnosis have advanced disease with projected 5-year survival rates of 30%. In those patients with distant metastatic or previously treated recurrent disease, response rate to the standard regimen of cisplatin and 5-fluorouracil is approximately 30%. The authors investigated the use of paclitaxel and carboplatin in a limited Phase II study in recurrent or metastatic SCCHN to evaluate tumor response, time to progression, survival, and toxicities of this regimen. METHODS: Patients with recurrent or metastatic SCCHN not amenable to further surgical or radiation therapy were treated with 200 mg/m(2) by 3-hour infusion of paclitaxel followed by carboplatin at an area under the concentration time curve of 6 mg/mL/minute via a 20-30-minute infusion every 3 weeks. RESULTS: Thirty-seven patients were enrolled. Ninety-five percent of patients had received prior surgery and postoperative radiotherapy. The overall response rate was 27% (95% confidence interval, 13-41%) with 1 complete and 9 PRs. Median survival of all patients was 4.9 months, and 1-year survival rate was 16%. There was a 43% response rate and 15.7-month median survival rate in patients with only distant metastatic disease and 38% response rate and a 4.5-month median survival in patients with locoregional and metastatic disease. The response rate for patients with only locoregional recurrence was 7% with a median survival of 4.8 months. Grade 3-4 myelotoxicity occurred in 24% of cycles administered. There were two treatment-related deaths due to neutropenic fever and one additional death on study may have been caused by treatment-induced thrombocytopenia. CONCLUSIONS: The combination of paclitaxel and carboplatin is significantly myelotoxic and ineffective in patients with previously treated locoregionally recurrent SCCHN, whereas it deserves further evaluation in those patients with distant metastatic disease alone. In those patients with locoregional disease, other more innovative treatments are needed.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma de Células Escamosas/tratamiento farmacológico , Neoplasias de Cabeza y Cuello/tratamiento farmacológico , Adulto , Anciano , Carboplatino/administración & dosificación , Carboplatino/efectos adversos , Carcinoma de Células Escamosas/patología , Progresión de la Enfermedad , Femenino , Factor Estimulante de Colonias de Granulocitos/administración & dosificación , Neoplasias de Cabeza y Cuello/patología , Humanos , Infusiones Intravenosas , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/tratamiento farmacológico , Recurrencia Local de Neoplasia/patología , Neutropenia/inducido químicamente , Paclitaxel/administración & dosificación , Paclitaxel/efectos adversos , Análisis de Supervivencia , Trombocitopenia/inducido químicamente , Resultado del Tratamiento
13.
Otolaryngol Head Neck Surg ; 125(4): 393-6, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11593178

RESUMEN

OBJECTIVE: To examine the pattern of spread regarding recurrent disease in primary head and neck squamous cell carcinoma. STUDY DESIGN AND SETTING: A retrospective study reviewed 128 patients who underwent primary tumor resection and postoperative radiation and/or chemoradiation for squamous cell carcinoma at Loyola University Medical Center from July 1993 to August 1998. Patterns of spread of recurrent disease were grouped according to site of recurrence and compared with the histopathology. RESULTS: Of 128 patients, 40 (32%) had recurrent disease, 22 (17%) died without disease, and 66 (51%) are disease free. Although the recurrences in patients who were N0 were primarily local-regional (8/11), the majority of recurrences in patients that were N+ with extracapsular nodal spread involved distant sites (18/24); 17/18 involved metastasis to the lung. SIGNIFICANCE: This study gives the first report at our institution of patterns of spread in recurrent head and neck squamous cell cancer and compares these patterns within subgroups of patients based on the extent of neck disease at the time of primary surgical resection. CONCLUSION: Not only was there a higher rate of recurrent disease in patients with extracapsular nodal spread, there was a much higher involvement of distant metastatic sites as opposed to local-regional recurrence more often seen with the N0 neck. The most common site of distant metastasis was the lung.


Asunto(s)
Carcinoma de Células Escamosas/patología , Neoplasias de Cabeza y Cuello/patología , Recurrencia Local de Neoplasia/patología , Carcinoma de Células Escamosas/secundario , Humanos , Metástasis de la Neoplasia , Recurrencia Local de Neoplasia/epidemiología , Estudios Retrospectivos
14.
Otolaryngol Head Neck Surg ; 125(3): 205-12, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11555755

RESUMEN

OBJECTIVES: This study determined whether mobilization of immune inhibitory CD34+ cells by head and neck squamous cell carcinomas (HNSCC) is most prominent in patients who are node positive and whether these CD34+ cells could differentiate into immune stimulatory dendritic cells. STUDY DESIGN AND SETTING: Peripheral blood from patients with head and neck cancer was used to measure the frequency of CD34+ cells and their capacity to differentiate into immune stimulatory dendritic cells. RESULTS: This study demonstrated that increased CD34+ cell levels were most prominent in patients who were node positive and patients with recurrent disease. These CD34+ cells differentiated into dendritic cells that were able to present tetanus toxoid to autologous T-cells. CONCLUSIONS: Immune suppressive CD34+ cells that are prominent in patients with HNSCC who are node positive are able to develop into immune stimulatory dendritic cells. SIGNIFICANCE: Differentiation of tumor-mobilized CD34+ cells into dendritic cells may be an immunotherapeutic approach to stimulate antitumor reactivity.


Asunto(s)
Antígenos CD34/sangre , Carcinoma de Células Escamosas/inmunología , Diferenciación Celular , Células Dendríticas/inmunología , Neoplasias de Cabeza y Cuello/inmunología , Presentación de Antígeno , Antígenos CD34/fisiología , Carcinoma de Células Escamosas/sangre , Factor Estimulante de Colonias de Granulocitos y Macrófagos/sangre , Neoplasias de Cabeza y Cuello/sangre , Humanos , Interferón gamma/metabolismo , Recurrencia Local de Neoplasia/inmunología , Linfocitos T/metabolismo
15.
ORL J Otorhinolaryngol Relat Spec ; 63(4): 192-201, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11408811

RESUMEN

The detection and treatment of metastatic cancer continues to be a challenge for the head and neck oncologist. Unfortunately, head and neck cancer patients who develop distant metastases commonly present late in their course and rapidly succumb to their disease, despite advances in imaging technologies and increased sophistication of biochemical analyses. The development of a rational approach to detection and treatment of metastatic head and neck cancers should begin with an understanding of how these tumors occur and which patients are at greatest risk for developing them. This article presents an overview of the biological processes resulting in the speed of a malignancy from one site to another, with particular attention to head and neck carcinomas. The basic histopathologic, immunology and biochemical abnormalities associated with the development of these secondary tumors are also discussed.


Asunto(s)
Neoplasias de Cabeza y Cuello/patología , Metástasis de la Neoplasia/patología , Transformación Celular Neoplásica , Humanos , Invasividad Neoplásica , Estadificación de Neoplasias , Neoplasias Primarias Secundarias/patología , Neovascularización Patológica
16.
Hum Immunol ; 62(4): 332-41, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11295465

RESUMEN

CD34(+) progenitor cells have previously been shown to be mobilized in patients with squamous cell carcinoma of the head and neck (HNSCC). The present study showed that these CD34(+) cells inhibit the capacity of intratumoral lymphoid cells to become activated in response to stimulation through the TCR/CD3 complex. The mechanisms that could lead to the accumulation of CD34(+) cells within the tumor tissue were assessed. This was accomplished through in vitro studies that determined if HNSCC produce soluble factors that chemoattract CD34(+) cells. The migration of cord blood CD34(+) cells, which were used as a readily available source of progenitor cells, was stimulated by products derived from HNSCC explants and primary HNSCC cultures. This stimulated migration was due to chemotaxis because it was dependent on an increasing gradient of HNSCC-derived products. CD34(+) cells that were isolated from the peripheral blood of HNSCC patients were similarly chemoattracted to the HNSCC-derived products. The majority of the chemotactic activity produced by HNSCC could be attributed to vascular endothelial cell growth factor (VEGF). These studies indicate that HNSCC can chemoattract immune inhibitory CD34(+) progenitor cells through their production of VEGF.


Asunto(s)
Antígenos CD34 , Carcinoma de Células Escamosas/metabolismo , Movimiento Celular/fisiología , Quimiotaxis/fisiología , Factores de Crecimiento Endotelial/metabolismo , Neoplasias de Cabeza y Cuello/metabolismo , Células Madre Hematopoyéticas/fisiología , Linfocinas/metabolismo , Carcinoma de Células Escamosas/patología , Sangre Fetal/citología , Neoplasias de Cabeza y Cuello/patología , Humanos , Terapia de Inmunosupresión , Linfocitos/inmunología , Factor A de Crecimiento Endotelial Vascular , Factores de Crecimiento Endotelial Vascular
17.
Arch Pathol Lab Med ; 125(2): 271-3, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11175650

RESUMEN

Primary malignant melanoma of the larynx is a rare clinical entity. Only 53 cases have been reported in the medical literature to date. This report describes a case of primary malignant melanoma arising in the larynx and diagnosed by histologic examination of an excisional biopsy specimen. The patient was a 53-year-old man with a history of smoking and hoarseness. There was no clinical evidence of other primary malignant melanocytic lesions. Microscopically, the tumor consisted of polygonal-epithelioid cells admixed with more elongated, spindle-shaped cells. The majority of the cells demonstrated dark brown cytoplasmic and nuclear melanin. Marked pleomorphism and abnormal mitoses were also identified. Despite significant ulceration and disruption of the epithelium, in situ malignant melanocytes were recognized within the remaining portion of the epithelium. Immunohistochemical studies were positive for S100, HMB-45, and vimentin, while cytokeratin and iron stains were negative. Based on the clinical and histologic findings, a diagnosis of primary malignant melanoma of the larynx was established.


Asunto(s)
Neoplasias Laríngeas/diagnóstico , Melanoma/diagnóstico , Antígenos de Neoplasias , Biopsia , Núcleo Celular/química , Citoplasma/química , Ronquera , Humanos , Inmunohistoquímica , Neoplasias Laríngeas/inmunología , Neoplasias Laríngeas/patología , Masculino , Melaninas/análisis , Melanocitos/patología , Melanoma/inmunología , Melanoma/patología , Antígenos Específicos del Melanoma , Persona de Mediana Edad , Proteínas de Neoplasias/análisis , Proteínas S100/análisis , Fumar , Tomografía Computarizada por Rayos X , Vimentina/análisis , Pliegues Vocales/patología
18.
Skull Base ; 11(3): 207-18, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17167622

RESUMEN

The etiology, classification, clinical presentation, complications, and intravascular routes to image and treat carotid-cavernous fistulas percutaneously are described. Endoarterial and transvenous approaches (through the jugular, inferior petrosal, or cavernous veins) are discussed in relation to the etiology, size, and characteristics of the fistulas, as well as in relation to the planned therapeutic approach and its possible complications. Possible outcomes, with particular attention to the internal carotid circulation, side effects, and complications also are discussed in relation to etiology and type of fistula. Four exemplary cases are presented.

19.
Arch Pathol Lab Med ; 124(9): 1356-60, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10975938

RESUMEN

Craniopharyngiomas are histologically and cytologically benign epithelial tumors of the central nervous system that may be locally aggressive and tend to recur after excision. Malignant change in craniopharyngiomas is extremely rare; we found only 4 such reports in the literature. In this report, we describe a case of squamous cell carcinoma arising in a previously benign craniopharyngioma in a 42-year-old woman. The patient was diagnosed with craniopharyngioma in 1982; during the subsequent 15 years she experienced 7 tumor recurrences, for which surgical resections and 3 courses of radiotherapy were performed. In 1998, the tumor recurred with involvement of the nasal cavity and sphenoid and ethmoid sinuses. Histologic evaluation revealed foci of typical adamantinomatous craniopharyngioma associated with a moderately differentiated squamous cell carcinoma. The transition of typical craniopharyngioma to squamous cell carcinoma was well demonstrated, suggesting that carcinoma arose from the underlying craniopharyngioma. Radiation may have been a contributing factor to carcinogenesis in this case.


Asunto(s)
Carcinoma de Células Escamosas/patología , Craneofaringioma/patología , Craneofaringioma/cirugía , Recurrencia Local de Neoplasia , Neoplasias Hipofisarias/patología , Neoplasias Hipofisarias/cirugía , Adulto , Carboplatino/uso terapéutico , Craneofaringioma/terapia , Femenino , Humanos , Imagen por Resonancia Magnética , Paclitaxel/uso terapéutico , Neoplasias Hipofisarias/terapia , Radioterapia , Proteína p53 Supresora de Tumor/análisis
20.
Arch Pathol Lab Med ; 124(6): 883-7, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10835527

RESUMEN

Mucormycosis is an infection caused by a group of fungi in the order Mucorales in the phylum Zygomycota. The most well-known form of this disease is rhinocerebral mucormycosis, which usually develops in diabetic or immunocompromised patients. The fungal hyphal elements are easily detected in biopsy specimens by direct or histologic examination. However, the confirmatory identification of the genus or species requires culture of the specimen. This article presents a case of rhinocerebral mucormycosis in which presumptive identification of the genus was made without microbiologic cultures and was based on the extraordinarily rare appearance of fungal sporangia and sporangiospores in histologic tissue sections. Identification of these structures allowed an early and accurate diagnosis of rhinocerebral invasive mucormycosis.


Asunto(s)
Encefalopatías/microbiología , Mucormicosis/patología , Enfermedades de los Senos Paranasales/microbiología , Rhizopus/clasificación , Adulto , Trasplante de Médula Ósea , Encefalopatías/patología , Desbridamiento , Diagnóstico Diferencial , Resultado Fatal , Humanos , Leucemia Mielógena Crónica BCR-ABL Positiva/terapia , Masculino , Mucormicosis/microbiología , Mucormicosis/terapia , Enfermedades de los Senos Paranasales/patología , Complicaciones Posoperatorias , Rhizopus/aislamiento & purificación , Rhizopus/fisiología
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