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1.
ACS Omega ; 6(47): 31901-31906, 2021 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-34870012

RESUMEN

Within food wastes, including edible and inedible parts, fat biomasses represent a significant portion, often uneconomically used or improperly disposed causing pollution issues. Interesting perspectives for their management and valorization could be opened by conversion of fatty acids (FAs), which are their main constituents, into α-hydroxy FAs (α-HFAs), fine chemicals of great, but largely untapped potential, possibly due to current poor availability. Here, a simple and efficient procedure is reported to α-chlorinate FAs with trichloroisocyanuric acid (TCCA), a green halogenating agent, under solvent-free conditions and to directly convert the resultant α-chloro FAs, without previous purification, into α-HFAs. The procedure was applied to stearic, palmitic, and myristic acid and, with analogous success, to their mixture, ad hoc created to simulate a FAs mixture obtainable from a fat biomass.

2.
J Org Chem ; 86(21): 15712-15716, 2021 11 05.
Artículo en Inglés | MEDLINE | ID: mdl-34643386

RESUMEN

Cyclic ketones were quickly and quantitatively converted to 5-, 6-, and 7-membered lactones, very important synthons, by treatment with Oxone, a cheap, stable, and nonpollutant oxidizing reagent, in 1 M NaH2PO4/Na2HPO4 water solution (pH 7). Under such simple and green conditions, no hydroxyacid was formed, thus making the adoption of more complex and non-eco-friendly procedures previously developed to avoid lactone hydrolysis unnecessary. With some changes, the method was successfully applied also to water-insoluble ketones such as adamantanone, acetophenone, 2-indanone, and the challenging cycloheptanone.


Asunto(s)
Cetonas , Agua , Lactonas , Oxidación-Reducción , Ácidos Sulfúricos
3.
Carbohydr Res ; 499: 108229, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33401228

RESUMEN

Heterogeneous solid catalysis by the commercially available perfluorosulfonic ionomer Aquivion-H allowed 1,2:5,6-diacetonide of d-mannitol (1), immediate precursor of important unichiral C3-synthons, to be efficiently obtained from d-mannitol and 2,2-dimethoxypropane in DMF at room temperature. The 1,2-monoacetonide, whose intermediate formation is the rate-limiting step, could be almost completely converted into 1 with limited concurrent transformation of 1 into triacetonides. In line with recent literature reports, these results indicate that heterogeneous catalysis by Aquivion-H surpasses the performances of homogeneous acidic catalysis assuring, presumably for its peculiar morphology, a higher product selectivity. Easy recovery at the end of the reaction and recyclability are additional advantages of this solid acid catalyst.


Asunto(s)
Glucocorticoides/química , Manitol/química , Catálisis , Conformación Molecular
4.
Am J Clin Pathol ; 155(1): 64-68, 2021 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-32995855

RESUMEN

OBJECTIVES: We performed data collection concerning the coronavirus disease 2019 (COVID-19) pandemic-related delay in the diagnosis of cancers to individuate proper corrective procedures. METHODS: A comparison was made among the number of first pathologic diagnoses of malignancy made from weeks 11 to 20 of 2018, 2019, and 2020 at seven anatomic pathology units serving secondary care hospitals in northern-central Italy. RESULTS: Cancer diagnoses fell in 2020 by 44.9% compared with the average number recorded in 2018 and 2019. Melanoma and nonmelanoma skin cancer represented 56.7% of all missing diagnoses. The diagnostic decrease in colorectal (-46.6%), prostate (-45%), and bladder (-43.6%) cancer was the most relevant among internal malignancies; for prostate, however, high-grade tumors were only moderately affected (-21.7%). CONCLUSIONS: Diagnosis of cutaneous malignancies was mostly affected by the lockdown; among internal malignancies, corrective actions were mostly needed for colorectal cancer and invasive bladder cancer.


Asunto(s)
COVID-19/prevención & control , Diagnóstico Tardío/tendencias , Detección Precoz del Cáncer/tendencias , Neoplasias/diagnóstico , Distanciamiento Físico , COVID-19/epidemiología , Humanos , Italia/epidemiología , Pandemias
5.
PLoS One ; 15(8): e0236466, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32764764

RESUMEN

AIM: The present work concerns the comparison of the performances of three systems for dosimetry in RPT that use different techniques for absorbed dose calculation (organ-level dosimetry, voxel-level dose kernel convolution and Monte Carlo simulations). The aim was to assess the importance of the choice of the most adequate calculation modality, providing recommendations about the choice of the computation tool. METHODS: The performances were evaluated both on phantoms and patients in a multi-level approach. Different phantoms filled with a 177Lu-radioactive solution were used: a homogeneous cylindrical phantom, a phantom with organ-shaped inserts and two cylindrical phantoms with inserts different for shape and volume. A total of 70 patients with NETs treated by PRRT with 177Lu-DOTATOC were retrospectively analysed. RESULTS: The comparisons were performed mainly between the mean values of the absorbed dose in the regions of interest. A general better agreement was obtained between Dose kernel convolution and Monte Carlo simulations results rather than between either of these two and organ-level dosimetry, both for phantoms and patients. Phantoms measurements also showed the discrepancies mainly depend on the geometry of the inserts (e.g. shape and volume). For patients, differences were more pronounced than phantoms and higher inter/intra patient variability was observed. CONCLUSION: This study suggests that voxel-level techniques for dosimetry calculation are potentially more accurate and personalized than organ-level methods. In particular, a voxel-convolution method provides good results in a short time of calculation, while Monte Carlo based computation should be conducted with very fast calculation systems for a possible use in clinics, despite its intrinsic higher accuracy. Attention to the calculation modality is recommended in case of clinical regions of interest with irregular shape and far from spherical geometry, in which Monte Carlo seems to be more accurate than voxel-convolution methods.


Asunto(s)
Lutecio/química , Fantasmas de Imagen/estadística & datos numéricos , Radioisótopos/química , Radiometría/estadística & datos numéricos , Receptores de Péptidos/aislamiento & purificación , Algoritmos , Humanos , Método de Montecarlo , Dosis de Radiación , Receptores de Péptidos/química , Estudios Retrospectivos
6.
Phys Med ; 57: 153-159, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30738519

RESUMEN

BACKGROUND: At present activity quantification is one of the most critical step in dosimetry calculation, and Partial Volume Effect (PVE) one of the most important source of error. In recent years models based upon phantoms that incorporate hot spheres have been used to establish recovery models. In this context the goal of this study was to point out the most critical issues related to PVE and to establish a model closer to a biological imaging environment. METHODS: Two different phantoms, filled with a 177Lu solution, were used to obtain the PVE Recovery Coefficients (RCs): a phantom with spherical inserts and a phantom with organ-shaped inserts. Two additional phantoms with inserts of various geometrical shapes and an anthropomorphic phantom were acquired to compare the real activities to predicted values after PVE correction. RESULTS: The RCs versus volume of the inserts produced two different curves, one for the spheres and one for the organs. After PVE correction, accuracy on activity quantification averaged over all inserts of three test phantoms passed from -26% to 1.3% (from 26% to 10% for absolute values). CONCLUSION: RCs is a simple method for PVE correction easily applicable in clinical routine. The use of two different models for organs and lesions has permitted to closely mimic the situation in a living subject. A marked improvement in the quantification of activity was observed when PVE correction was adopted, even if further investigations should be performed for more accurate models of PVE corrections.


Asunto(s)
Octreótido/análogos & derivados , Radioterapia , Receptores de Somatostatina/metabolismo , Tomografía Computarizada de Emisión de Fotón Único , Humanos , Procesamiento de Imagen Asistido por Computador , Fantasmas de Imagen
7.
Neuroradiol J ; 31(2): 193-195, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28735554

RESUMEN

A 56-year-old man with behavioural disorders and facial-brachio-crural right hemiparesis presented with a brain lesion studied with computed tomography, magnetic resonance imaging and brain biopsy, leading to the diagnosis of cerebral vasculitis. Hepatitis C virus (HCV) infection in a phase of activity, without cryoglobulins, was also detected. Brain biopsy, laboratory analysis and response to a specific therapy supported the diagnosis of central nervous system vasculitis that was HCV related.


Asunto(s)
Hepatitis C/complicaciones , Imagen por Resonancia Magnética , Vasculitis del Sistema Nervioso Central/diagnóstico por imagen , Vasculitis del Sistema Nervioso Central/virología , Biopsia , Crioglobulinas/análisis , Diagnóstico Diferencial , Humanos , Espectroscopía de Resonancia Magnética , Masculino , Persona de Mediana Edad , Tomografía Computarizada por Rayos X
8.
Sci Total Environ ; 593-594: 677-687, 2017 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-28363180

RESUMEN

The integration of chemical and biological data in aerosol studies represents a new challenge in atmospheric science. In this perspective it will be possible to gain a clearer and deeper comprehension of biogeochemical cycles in the atmosphere. In this view, this study aimed to investigate the relationships occurring between bacterial populations and PM chemical composition in one of the most polluted and urbanized areas in Europe: the Po Valley (Italy). Moreover, seasonality, long- and short-range transports were also evaluated to investigate the influence on airborne bacterial communities. PM samples were collected in two cities of the Po Valley (Milan and Venice) characterized by different meteorological conditions and atmospheric pollutant sources. Samples were analysed for water-soluble inorganic ions (WSIIs) and bacterial community structure. Chemical and biological data were jointly processed by using redundancy discriminate analysis (RDA), while the influence of atmospheric circulation was evaluated by using wind ground data and back-trajectories analysis. Results showed strong seasonal shifts of bacterial community structure in both cities, while a different behaviour was observed for air mass circulation at Milan ad Venice sites: long-range transport significantly affected bacterial populations in Milan whereas local ground wind had more influence in the Venice area. Moreover, difference in taxonomic composition can be mostly addressed to the characteristics of sampling sites. This evidence could suggest that, while PM composition is influenced by long-range transport, bacterial populations are affected, besides transport, by other factors (i.e., season and sampling site location). This perspective allow to better understand and explain airborne bacterial community behaviour.


Asunto(s)
Microbiología del Aire , Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente , Material Particulado/análisis , Estaciones del Año , Ciudades , Italia , Tamaño de la Partícula
9.
Bioresour Technol ; 221: 588-597, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27689352

RESUMEN

A laboratory scale nutrient removal activated sludge system coupled with an anaerobic side-stream reactor was operated for 300 days treating real urban wastewater. A significant decrease in sludge production was obtained increasing the anaerobic solid retention time (SRTASSR) and decreasing the sludge interchange ratio (IR). In this study, the microbial community structure was analyzed and compared with the sludge reduction performance. Quantitative polymerase chain reaction analyses encoding 16 ribosomal RNA and functional genes revealed a wide diversity of phylogenetic groups in each experimental period, resulting from long solids retention time and recirculation of sludge under aerobic, anoxic and anaerobic conditions. However, decreasing SRTASSR from 10 to 2.5d and increasing IR from 27 to 100%, an increasing selection of both fermenting bacteria able to release extracellular polymeric substances and hydrolyze organic matter and slow growing bacteria involved in nutrient removal were detected and linked to the sludge reduction mechanisms.


Asunto(s)
Reactores Biológicos/microbiología , Consorcios Microbianos/fisiología , Aguas del Alcantarillado , Eliminación de Residuos Líquidos/instrumentación , Anaerobiosis , Archaea/genética , Archaea/metabolismo , Bacterias/genética , Bacterias/metabolismo , Consorcios Microbianos/genética , Filogenia , Aguas del Alcantarillado/química , Eliminación de Residuos Líquidos/métodos , Aguas Residuales
10.
Appl Microbiol Biotechnol ; 97(11): 4727-36, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23604562

RESUMEN

The study of airborne biological particles ('bioaerosols') has gained interest in recent years, due to an increasing amount of evidence suggesting that this fraction of airborne particulate matter may play a critical role in the negative effects of aerosols on biological systems. Pioneer investigations demonstrated that bacteria do exist in the atmosphere and can be metabolically active, although studies have not proved whether they actually form ecological communities or are merely assemblages of organisms passively transported from different sources. For a long time, cultivation-based methods have been the gold standard to describe and quantify airborne microorganisms. However, the use of culture-independent techniques and, more recently, of the next-generation sequencing-based methods, has improved the ability of the scientific community to investigate bioaerosols in detail and to address further research questions, such as the temporal and spatial variability of airborne bacterial assemblages, the environmental factors affecting this variability and the potential sources of atmospheric bacteria. This paper provides a systematic review of the state-of-the-art methodologies used in the study of airborne bacteria to achieve each of the aforementioned research objectives, as well as the main results obtained so far. Critical evaluations of the current state of the knowledge and suggestions for further researches are provided.


Asunto(s)
Microbiología del Aire , Bacterias/clasificación , Biodiversidad , Metagenómica/métodos , Técnicas Bacteriológicas/métodos , Secuenciación de Nucleótidos de Alto Rendimiento/métodos
11.
ISME J ; 7(8): 1483-92, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23535918

RESUMEN

High-elevation cold environments are considered ideal places to test hypotheses about mechanisms of bacterial colonization and succession, and about bacterial biogeography. Debris-covered glaciers (glaciers whose ablation area is mainly covered by a continuous layer of rock debris fallen from the surrounding mountains) have never been investigated in this respect so far. We used the Illumina technology to analyse the V5 and V6 hypervariable regions of the bacterial 16S rRNA gene amplified from 38 samples collected in July and September 2009 at different distances from the terminus on two debris-covered glaciers (Miage and Belvedere--Italian Alps). Heterotrophic taxa-dominated communities and bacterial community structure changed according to ice ablation rate, organic carbon content of the debris and distance from the glacier terminus. Bacterial communities therefore change during downwards debris transport, and organic carbon of these recently exposed substrates is probably provided more by allochthonous deposition of organic matter than by primary production by autotrophic organisms. We also investigated whether phylotypes of the genus Polaromonas, which is ubiquitous in cold environments, do present a biogeographical distribution by analysing the sequences retrieved in this study together with others available in the literature. We found that the genetic distance among phylotypes increased with geographic distance; however, more focused analyses using discrete distance classes revealed that both sequences collected at sites <100 km and at sites 9400-13,500 km to each other were more similar than those collected at other distance classes. Evidences of biogeographic distribution of Polaromonas phylotypes were therefore contrasting.


Asunto(s)
Fenómenos Fisiológicos Bacterianos , Biodiversidad , Comamonadaceae/fisiología , Cubierta de Hielo/microbiología , Microbiología del Suelo , Bacterias/clasificación , Bacterias/genética , Técnicas de Tipificación Bacteriana , Comamonadaceae/genética , Italia , Filogeografía , ARN Ribosómico 16S/genética , Suelo/química
12.
Appl Microbiol Biotechnol ; 97(14): 6561-70, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23053100

RESUMEN

Despite airborne microorganisms representing a relevant fraction of atmospheric suspended particles, only a small amount of information is currently available on their abundance and diversity and very few studies have investigated the environmental factors influencing the structure of airborne bacterial communities. In this work, we used quantitative PCR and Illumina technology to provide a thorough description of airborne bacterial communities in the urban area of Milan (Italy). Forty samples were collected in 10-day sampling sessions, with one session per season. The mean bacterial abundance was about 104 ribosomal operons per m³ of air and was lower in winter than in the other seasons. Communities were dominated by Actinobacteridae, Clostridiales, Sphingobacteriales and few proteobacterial orders (Burkholderiales, Rhizobiales, Sphingomonadales and Pseudomonadales). Chloroplasts were abundant in all samples. A higher abundance of Actinobacteridae, which are typical soil-inhabiting bacteria, and a lower abundance of chloroplasts in samples collected on cold days were observed. The variation in community composition observed within seasons was comparable to that observed between seasons, thus suggesting that airborne bacterial communities show large temporal variability, even between consecutive days. The structure of airborne bacterial communities therefore suggests that soil and plants are the sources which contribute most to the airborne communities of Milan atmosphere, but the structure of the bacterial community seems to depend mainly on the source of bacteria that predominates in a given period of time.


Asunto(s)
Microbiología del Aire , Bacterias/aislamiento & purificación , Biodiversidad , Bacterias/clasificación , Bacterias/genética , ADN Bacteriano/genética , Ambiente , Monitoreo del Ambiente , Italia , ARN Ribosómico 16S/genética , Estaciones del Año , Remodelación Urbana
13.
Mod Pathol ; 24(1): 126-37, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20852594

RESUMEN

This work has evaluated the potential superiority of a morphomolecular classification based on the combination of clinicopathologic and molecular features of colorectal cancers. A cohort of 126 colorectal carcinomas was investigated by unsupervised hierarchical clustering analysis to combine 13 routinely assessed clinicopathologic features and all five molecular markers recently suggested by Jass' classification to distinguish four molecular subtypes of sporadic colorectal carcinomas. Survival analysis was assessed by a Cox proportional hazards model. A clear separation into three prognostically significant groups was identified: cluster A and cluster C were associated with good prognosis and cluster B with poor prognosis (P=0.006). Clinicopathologic and molecular features of cluster A and cluster B tumors were strongly concordant with colorectal cancer profiles characterized by microsatellite instability or by chromosomal instability, respectively. The clinicopathologic features of cluster C tumors were suggestive of a less aggressive disease than cluster B tumors. Genetically, they appeared intermediate between cluster A and cluster B tumors, as they were mainly microsatellite stable tumors showing high levels of both MGMT methylation and loss of heterozygosity. Chromosomal instability was significantly lower in cluster C than in cluster B tumors. A more accurate tumor classification should combine the prognostic power of clinicopathologic parameters with molecular biomarkers that provide information regarding the natural history of the cancer. Hierarchical clustering seems to be a useful, promising and powerful tool for further translational studies and should lead us to define a diagnostic and prognostic signature for different carcinomas.


Asunto(s)
Adenocarcinoma/genética , Adenocarcinoma/patología , Inestabilidad Cromosómica , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , Inestabilidad de Microsatélites , Adenocarcinoma/mortalidad , Anciano , Biomarcadores de Tumor/genética , Análisis por Conglomerados , Estudios de Cohortes , Neoplasias Colorrectales/mortalidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Pronóstico , Modelos de Riesgos Proporcionales , Tasa de Supervivencia
14.
J Transl Med ; 8: 112, 2010 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-21059221

RESUMEN

BACKGROUND: Colorectal cancer can be efficiently treated when found at early stages, thus the search for novel markers is of paramount importance. Since inflammation is associated with cancer progression and angiogenesis, we investigated expression of cytokines like IL-6 and other mediators that play a key role in the innate immune system, in particular toll like receptor 4 (TLR4), in the microenvironment of lesions from different stages of colon disease progression, from ulcerative colitis to adenoma and adenocarcinoma to find useful markers. METHODS: The presence of inflammatory cells and expression of key cytokines involved in the inflammation process were quantified by immunohistochemistry in specific tissue compartments (epithelial, stromal, endothelial) by immunohistochemistry. A murine azoxymethane/dextran sulfate model in which Tir8, a negative regulator of the inflammatory response, was ablated was used to confirm the clinical observations. 116 Archival tissue samples from patients with different stages of colorectal disease: 13 cases of ulcerative colitis (UC), 34 tubular or tubulo-villous adenomas (AD), and 53 infiltrating adenocarcinomas. 16 specimens of healthy mucosa surgically removed with the cancerous tissue were used as a control. RESULTS: The differences between healthy tissues and the diverse lesions was characterized by a marked inflammatory-angiogenic reaction, with significantly (P < 0.05) higher numbers of CD68, CD15, and CD31 expressing cells in all diseased tissues that correlated with increasing grade of malignancy. We noted down-regulation of a potential modulator molecule, Hepatocyte Growth Factor, in all diseased tissues (P < 0.05). TLR-4 and IL6 expression in the tumor microenvironment were associated with adenocarcinoma in human samples and in the murine model. We found that adenocarcinoma patients (pT1-4) with higher TLR-4 expression in stromal compartment had a significantly increased risk in disease progression. In those patients with a diagnosis of pT3 (33 cases) colon cancer, those with very high levels of TLR-4 in the tumor stroma relapsed significantly earlier than those with lower expression levels. CONCLUSIONS: These data suggest that high TLR-4 expression in the tumor microenvironment represents a possible marker of disease progression in colon cancer.


Asunto(s)
Neoplasias Colorrectales/patología , Receptor Toll-Like 4/metabolismo , Animales , Antígenos CD/inmunología , Neoplasias Colorrectales/inmunología , Neoplasias Colorrectales/metabolismo , Citocinas/metabolismo , Modelos Animales de Enfermedad , Humanos , Inmunohistoquímica , Ratones , Ratones Noqueados , Pronóstico
15.
Virchows Arch ; 455(6): 527-31, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19908063

RESUMEN

A case of a colonic carcinoma showing a pancreatic acinar cell differentiation is described for the first time. A 65-year-old woman underwent surgical resection for an ulcerated protruding tumour of 4 x 2.5 cm in size on the anterior wall of the sigmoid colon. Histologically, tumour cells were organized in acinar structures resembling pancreatic acini and in solid nests and ribbons or diffusely infiltrated as poorly cohesive cells. Lymph nodes and femur metastases displayed the same histological features. The ultrastructural analysis of the primary tumour indicated the presence of zymogen-like granules in the cytoplasm of tumour cells. Immunohistochemically, both acinar and diffuse patterns of growth showed an intense staining for trypsin, chymotrypsin and BCL10 and a weaker immunoreactivity for lipase and carboxyl ester hydrolase. Most tumour cells were cytokeratin 20, CDX2 and p53 positive; whereas, mucin (MUC)2 immunoreactivity was observed only in the signet ring cells present in the diffuse pattern and chromogranin A in rare isolated tumour cells. No immunoreactivity was observed for cytokeratin 7, MUC1, MUC5AC, pancreatic amylase or PDX1. There was no evidence of a pancreatic acinar cell carcinoma or of heterotopic pancreatic tissue. A colonic origin ought to be suspected when a metastatic carcinoma of unknown primary shows an acinar differentiation.


Asunto(s)
Carcinoma de Células Acinares/patología , Neoplasias del Colon/patología , Neoplasias Pancreáticas/patología , Anciano , Factor de Transcripción CDX2 , Diferenciación Celular , Resultado Fatal , Femenino , Proteínas de Homeodominio/metabolismo , Humanos , Inmunohistoquímica , Queratina-20/metabolismo , Metástasis Linfática , Proteína p53 Supresora de Tumor/metabolismo
16.
Hum Pathol ; 39(10): 1483-94, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18619649

RESUMEN

The aim of the study was to identify the impact on prognosis of hypoxia-inducible factor-1 genetic program in colorectal carcinomas and to develop an experimental procedure that would allow a reliable quantitative gene expression analysis in formalin-fixed and paraffin-embedded tissue. The expression of hypoxia-inducible factor-1alpha and 13 hypoxia-inducible factor-1 target genes (AMF, CAIX, VEGF, VEGFR1, VEGFR2, HGF, MET, TGFalpha, EGFR, IGF2, MMP2, PLAUR, NIX) was quantified by real-time polymerase chain reaction in 18 colorectal, poorly differentiated neuroendocrine carcinomas and in 60 invasive colorectal carcinomas. Moreover, hypoxia-inducible factor-1alpha protein expression was evaluated by immunohistochemistry. High levels of hypoxia-inducible factor-1alpha were positively associated with poorly differentiated neuroendocrine carcinoma histology (P < .005), poor differentiation (P < .025), presence of necrosis, and presence of microsatellite instability (P < .05). AMF, TGFalpha, IGF2, NIX, VEGF, and VEGFR2 transcripts were significantly higher in the very aggressive poorly differentiated neuroendocrine carcinomas than in exocrine colorectal carcinomas and TGFalpha expression was significantly associated with presence of lymph nodal metastases (P < .05). High levels of TGFalpha and NIX were significantly associated with decreased overall survival (P < .001; P < .01). The multivariate analysis showed that advanced stage, presence of lymph node metastases, and high TGFalpha expression had an independent effect on survival (P < .006; P < .01; P < .0006). Our study suggests an up-regulation of the hypoxia-inducible factor-1 transcriptional pathway in colorectal carcinomas. hypoxia-inducible factor-1alpha overexpression alone, has no impact on the prognosis of colorectal carcinomas likely because the consequences of hypoxia-inducible factor-1alpha expression/stabilization strongly depend on the genetic background of the transformed cells. Mechanisms leading to increased synthesis of hypoxia-inducible factor-1alpha mRNA via autocrine growth factor loops may play a crucial role in invasive growth in this site.


Asunto(s)
Adenocarcinoma/genética , Biomarcadores de Tumor/genética , Carcinoma Neuroendocrino/genética , Neoplasias Colorrectales/genética , Regulación Neoplásica de la Expresión Génica , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Adenocarcinoma/mortalidad , Adenocarcinoma/secundario , Anciano , Biomarcadores de Tumor/metabolismo , Carcinoma Neuroendocrino/mortalidad , Carcinoma Neuroendocrino/secundario , Neoplasias Colorrectales/mortalidad , Neoplasias Colorrectales/patología , Femenino , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Inmunohistoquímica , Ganglios Linfáticos/patología , Masculino , Inestabilidad de Microsatélites , Persona de Mediana Edad , Necrosis , Pronóstico , ARN Mensajero/metabolismo , ARN Neoplásico/análisis , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Tasa de Supervivencia , Transcripción Genética , Regulación hacia Arriba
17.
Pathol Res Pract ; 204(4): 219-33, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18304753

RESUMEN

Gastrointestinal stromal tumors (GISTs) are c-Kit-positive neoplasms of the digestive tract. Few studies have reported their real incidence and malignancy. Two systems of risk assessment of aggressive behavior were recently proposed. The aims of our study were (1) to ascertain the frequency of GISTs and their clinical behavior in a large series of cases with a long-term follow-up, (2) to evaluate the prognostic value of two well-known risk assessment classifications, and (3) to propose an alternative prognostic index based on our data. Statistical analyses were performed to identify possible predictors of malignant behavior. One hundred and eighteen out of 169 (70%) mesenchymal tumors were GISTs. They were located in the stomach (57%), small intestine (31%), colon/rectum (6%), and omentum/mesentery (6%). Eighteen cases (16%) showed malignant behavior, with local recurrence in eight cases and distant metastases in 11 cases. Fifteen of 114 (13%) patients died of disease within 74 months, whereas 63 (55%) patients were still alive after a median period of 78 months. At multivariate analysis, high-risk category (according to Fletcher's criteria), omental/colorectal site, and younger patient age were independent predictors of malignant behavior. In addition to the evaluation of risk category, tumor site and patient age helped to better identify patients requiring stricter monitoring.


Asunto(s)
Tumores del Estroma Gastrointestinal/epidemiología , Tumores del Estroma Gastrointestinal/patología , Recurrencia Local de Neoplasia , Adulto , Factores de Edad , Anciano , Supervivencia sin Enfermedad , Femenino , Tumores del Estroma Gastrointestinal/clasificación , Tumores del Estroma Gastrointestinal/mortalidad , Tumores del Estroma Gastrointestinal/terapia , Indicadores de Salud , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Modelos Biológicos , Invasividad Neoplásica , Metástasis de la Neoplasia , Estadificación de Neoplasias , Modelos de Riesgos Proporcionales , Medición de Riesgo , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento
18.
J Med Case Rep ; 1: 133, 2007 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-17997826

RESUMEN

BACKGROUND: Papillary thyroid carcinoma (PTC) and medullary thyroid carcinoma (MTC) have always been considered different from each other; in their incidence, their cell origin and their histopathological features. CASE PRESENTATION: This paper describes two rare cases of the simultaneous occurrence of MTC and PTC in the thyroid gland. Case 1 is unique for different reasons: (a) the patient was affected by both multicentric MTC and PTC; (b) a "composite thyroid carcinoma" with mixed feautures of MTC and PTC carcinomas was found in the istmus of the gland; and (c) these tumors were associated with diffuse lymphocytic-type thyroiditis (LT). Case 2 is notable for the long follow up: 16 years disease free. CONCLUSION: There are only 16 reports in the English medical literature describing a total of 20 cases of concurrent occurrence of both PTC and MTC in the same thyroid gland. We discuss whether the finding of another cancer in these patients was coincidental or from possible activation of a common tumorigenic pathway for both follicular and parafollicular thyroid cells.

19.
Surg Oncol ; 16 Suppl 1: S25-7, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18023174

RESUMEN

Hypoxia-inducible factor 1 (HIF-1) is a transcription factor that regulates gene expression in critical pathways involved in tumor growth and metastases. In our study we evaluated the expression of HIF-1alpha transcript and protein by quantitative real time PCR and by immunohistochemistry in a total of 78 colorectal carcinomas (CRCs) and in 8 samples of normal colorectal mucosa in order to identify the impact on prognosis of HIF-1alpha overexpression in CRCs. Our study demonstrates a significant up-regulation of HIF-1alpha mRNA as well as a high frequency of the protein immunoreactivity in colorectal cancers compared to normal samples. However, no significant correlation was found between HIF-1alpha immunohistochemical expression and any of the clinico-pathological parameters evaluated, with the only exception of the positive association between HIF-1alpha immunoreactivity and the presence of tumor necrosis. Analogously, high levels of HIF-1alpha mRNA were found to be correlated with a poor grade of tumor differentiation but no other significant association was observed. Despite the careful selection of the tumor samples, our findings do not appear to confirm, for colorectal cancers, the significant association between HIF-1alpha overexpression and tumor aggressiveness or unfavorable prognosis demonstrated for cancers of other sites. The lack of prognostic impact of HIF-1 in this site could be explained by an intricate interaction between the survival program mediated by HIF-1 and the genetic background of tumors cells in which its activation occurs.


Asunto(s)
Neoplasias Colorrectales/metabolismo , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Regulación hacia Arriba , Neoplasias Colorrectales/genética , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Inmunohistoquímica , ARN Mensajero/metabolismo
20.
Virchows Arch ; 448(3): 344-53, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16261379

RESUMEN

Gastric carcinomas (GCs) with high microsatellite instability (MSI) or an Epstein-Barr virus (EBV) infection are prevalently poorly differentiated adenocarcinomas with abundant lymphoid infiltration. The aims of the study were to clarify (1) if tumour-infiltrating lymphocytes (TILs) and cytotoxic-activated TILs are associated with a better clinical outcome in patients with GCs characterised for the presence of MSI and EBV; (2) if the nature and the activation status of TILs are involved in tumour cell apoptosis, evaluated using the M30 antibody, directed against a fragment of cytokeratin-18 caspase-cleaved during early steps of epithelial cell apoptosis. The immunophenotype of TILs and the tumour cell apoptosis were analysed with immunohistochemistry in 96 GCs, including 35 MSI GCs, and 61 GCs without MSI [microsatellite stable (MSS)], 17 of which were EBV+. MSI and MSS/EBV+ GCs displayed a significantly higher mean number of cytotoxic-activated TILs and apoptotic tumour cells than MSS/EBV- GCs (CD8+ TILs/HPF, 21.7 and 69.6 vs 6.4; T-cell intracellular antigen (TIA)-1+ TILs/HPF, 16.7 and 32.05 vs 5.2; granzyme B+ TILs/HPF, 7.5 and 8.6 vs 0.8; perforin+ TILs/HPF, 5.9 and 9.2 vs 0.9; and M30 IR tumour cells, 5.9 and 2.9 vs 2.3%). In addition to the most reliable clinico-pathological parameters (lymph node status, depth of tumour invasion and tumour stage), a univariate analysis showed that the presence of CD3+ TILs higher than 14.9 (p=0.01), CD8+ TILs higher than 9.5 (p<0.05) and MSI (p=0.02) were associated with better overall patient survival. Using a Cox regression model, only a high number of CD3+ TILs (p=0.02) and a low tumour stage (p=0.00001) were identified as independent prognostic factors. In conclusion, our study demonstrates that a high number of CD3+ and CD8+ TILs is a characteristic of MSI- and EBV-associated GCs and represents a favourable prognostic factor, independently of the pathogenesis of GCs.


Asunto(s)
Adenocarcinoma/mortalidad , Infecciones por Virus de Epstein-Barr/patología , Activación de Linfocitos/inmunología , Linfocitos Infiltrantes de Tumor/inmunología , Inestabilidad de Microsatélites , Neoplasias Gástricas/mortalidad , Linfocitos T/inmunología , Adenocarcinoma/inmunología , Adenocarcinoma/virología , Adulto , Anciano , Anciano de 80 o más Años , Apoptosis , Complejo CD3/metabolismo , Infecciones por Virus de Epstein-Barr/complicaciones , Femenino , Técnica del Anticuerpo Fluorescente Indirecta , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/aislamiento & purificación , Humanos , Técnicas para Inmunoenzimas , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Neoplasias Gástricas/inmunología , Neoplasias Gástricas/virología , Tasa de Supervivencia
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