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1.
Eur Phys J C Part Fields ; 78(8): 651, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30197571

RESUMEN

We present NNFF1.1h, a new determination of unidentified charged-hadron fragmentation functions (FFs) and their uncertainties. Experimental measurements of transverse-momentum distributions for charged-hadron production in proton-(anti)proton collisions at the Tevatron and at the LHC are used to constrain a set of FFs originally determined from electron-positron annihilation data. Our analysis is performed at next-to-leading order in perturbative quantum chromodynamics. We find that the hadron-collider data is consistent with the electron-positron data and that it significantly constrains the gluon FF. We verify the reliability of our results upon our choice of the kinematic cut in the hadron transverse momentum applied to the hadron-collider data and their consistency with NNFF1.0, our previous determination of the FFs of charged pions, kaons, and protons/antiprotons.

2.
Eur Phys J C Part Fields ; 77(12): 837, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-31997936

RESUMEN

We investigate the impact of displaced heavy-quark matching scales in a global fit. The heavy-quark matching scale µ m determines at which energy scale µ the QCD theory transitions from N F to N F + 1 in the variable flavor number scheme (VFNS) for the evolution of the parton distribution functions (PDFs) and strong coupling α S ( µ ) . We study the variation of the matching scales, and their impact on a global PDF fit of the combined HERA data. As the choice of the matching scale µ m effectively is a choice of scheme, this represents a theoretical uncertainty; ideally, we would like to see minimal dependence on this parameter. For the transition across the charm quark (from N F = 3 to 4), we find a large µ m = µ c dependence of the global fit χ 2 at NLO, but this is significantly reduced at NNLO. For the transition across the bottom quark (from N F = 4 to 5), we have a reduced µ m = µ b dependence of the χ 2 at both NLO and NNLO as compared to the charm. This feature is now implemented in xFitter 2.0.0, an open source QCD fit framework.

3.
Eur Phys J C Part Fields ; 77(11): 791, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-31997933

RESUMEN

The strong coupling constant α s is determined from inclusive jet and dijet cross sections in neutral-current deep-inelastic ep scattering (DIS) measured at HERA by the H1 collaboration using next-to-next-to-leading order (NNLO) QCD predictions. The dependence of the NNLO predictions and of the resulting value of α s ( m Z ) at the Z-boson mass m Z are studied as a function of the choice of the renormalisation and factorisation scales. Using inclusive jet and dijet data together, the strong coupling constant is determined to be α s ( m Z ) = 0.1157 ( 20 ) exp ( 29 ) th . Complementary, α s ( m Z ) is determined together with parton distribution functions of the proton (PDFs) from jet and inclusive DIS data measured by the H1 experiment. The value α s ( m Z ) = 0.1142 ( 28 ) tot obtained is consistent with the determination from jet data alone. The impact of the jet data on the PDFs is studied. The running of the strong coupling is tested at different values of the renormalisation scale and the results are found to be in agreement with expectations.

4.
Eur J Histochem ; 58(3): 2414, 2014 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-25308846

RESUMEN

Graft steatosis is a risk factor for poor initial function after liver transplantation. Biliary complications are frequent even after normal liver transplantation. A subnormothermic machine perfusion (MP20) preservation procedure was developed by our group with high potential for reducing injury to hepatocytes and sinusoidal cells of lean and fatty livers respect to conventional cold storage (CS). We report the response of the biliary tree to CS or MP20, in lean and obese Zucker rat liver. Dipeptidylpeptidase-IV (DPP-IV), crucial for the inactivation of incretins and neuropeptides, was used as a marker. Liver morphology and canalicular network of lean livers were similar after CS/reperfusion or MP20/reperfusion. CS preservation of fatty livers induced serious damage to the parenchyma and to the canalicular activity/expression of DPP-IV whereas with MP20 the morphology and canalicular network were similar to those of untreated lean liver. CS and MP20 had similar effects on DPP-IV activity and expression in the upper segments of the intrahepatic biliary tree of fatty livers. DPP-IV expression was significantly increased after MP20 respect to CS or to the controls, both for lean and obese animals. Our data support the superiority of MP20 over CS for preserving fatty livers. Dipeptidylpeptidase-IV activity and expression reveal decreased damage to the intrahepatic biliary tree in fatty livers submitted to subnormothermic machine-perfusion respect to conventional cold storage.


Asunto(s)
Sistema Biliar/patología , Dipeptidil Peptidasa 4/genética , Dipeptidil Peptidasa 4/metabolismo , Hígado Graso/enzimología , Hígado Graso/patología , Hígado/patología , Preservación de Órganos/métodos , Animales , Sistema Biliar/enzimología , Western Blotting , Regulación Enzimológica de la Expresión Génica , Inmunohistoquímica , Hígado/enzimología , Hígado/metabolismo , Masculino , Preservación de Órganos/normas , Perfusión , Ratas , Ratas Zucker
5.
Rev. argent. cir. plást ; 19(4): 97-102, 20130000. fig
Artículo en Español | LILACS, BINACIS | ID: biblio-1553866

RESUMEN

Se distingue en las fosas nasales la presencia de un estrecho o válvula y, de ella, se investiga específi camente su porción anterior conocida en la Especialidad de Cirugía Plástica como válvula nasal interna (VNI). Las características, disposición y relaciones de sus distintos componentes son analizados en esta presentación, puntualizando específi camente el singular comportamiento del mucoepitelio valvular con respecto a los cartílagos triangulares y cuadrangular. Se advierte sobre la posibilidad de complicaciones posoperatorias en el caso de indebido trato valvular. Se adjuntan preparados y sus correspondientes dibujos con el propósito de facilitar la comprensión de los hechos observados


Stands out the presence of a strait or valve in the nostrils, and about it, it's specifi cally investigated it's anterior portion known in the fi eld as internal nasal valve (INV). Characteristics, provision and relations of its individual components are discussed in this presentation, specifi cally pointing out the ubique behavior of the valvular mucosal epithelium in connection with the triangular and quadrangular cartilage. It warns out the possibility of post operative complications in case of improper valvular treatment. Attached preparations and their corresponding drawings in orden te facilitate the understanding of the observed facts.


Asunto(s)
Humanos , Masculino , Femenino , Rinoplastia/métodos , Constricción Patológica/cirugía , Cavidad Nasal/anatomía & histología
6.
Eur J Histochem ; 56(4): e41, 2012 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-23361237

RESUMEN

Given the scarcity of donors, moderately fatty livers (FLs) are currently being considered as possible grafts for orthotopic liver transplantation (OLT), notwithstanding their poor tolerance to conventional cold preservation. The behaviour of parenchymal and sinusoidal liver cells during transplantation is being studied worldwide. Much less attention has been paid to the biliary tree, although this is considered the Achille's heel even of normal liver transplantation. To evaluate the response of the biliary compartment of FLs to the various phases of OLT reliable markers are necessary. Previously we demonstrated that Alkaline Phosphatase was scarcely active in bile canaliculi of FLs and thus ruled it out as a marker. As an alternative, dipeptidylpeptidase-IV (DPP-IV), was investigated. This ecto-peptidase plays an important role in glucose metabolism, rapidly inactivating insulin secreting hormones (incretins) that are important regulators of glucose metabolism. DPP-IV inhibitors are indeed used to treat Type II diabetes. Neuropeptides regulating bile transport and composition are further important substrates of DPP-IV in the enterohepatic axis. DPP-IV activity was investigated with an azo-coupling method in the liver of fatty Zucker rats (fa/fa), using as controls lean Zucker (fa/+) and normal Wistar rats. Protein expression was studied by immunofluorescence with the monoclonal antibody (clone 5E8). In Wistar rat liver, DPP-IV activity and expression were high in the whole biliary tree, and moderate in sinusoid endothelial cells, in agreement with the literature. Main substrates of DPP-IV in hepatocytes and cholangiocytes could be incretins GLP-1 and GIP, and neuropeptides such as vasoactive intestinal peptide (VIP) and substance P, suggesting that these substances are inactivated or modified through the biliary route. In lean Zucker rat liver the enzyme reaction and protein expression patterns were similar to those of Wistar rat. In obese rat liver the patterns of DPP-IV activity and expression in hepatocytes reflected the morphological alterations induced by steatosis as lipid-rich hepatocytes had scarce activity, located either in deformed bile canaliculi or in the sinusoidal and lateral domains of the plasma membrane. These findings suggest that bile canaliculi in steatotic cells have an impaired capacity to inactivate incretins and neuropeptides. Incretin and/or neuropeptide deregulation is indeed thought to play important roles in obesity and insulin-resistance. No alteration in enzyme activity and expression was found in the upper segments of the biliary tree of obese respect to lean Zucker and Wistar rats. In conclusion, this research demonstrates that DPP-IV is a promising in situ marker of biliary functionality not only of normal but also of fatty rats. The approach, initially devised to investigate the behaviour of the liver during the various phases of transplantation, appears to have a much higher potentiality as it could be further exploited to investigate any pathological or stressful conditions involving the biliary tract (i.e., metabolic syndrome and cholestasis) and the response of the biliary tract to therapy and/or to surgery.


Asunto(s)
Dipeptidil Peptidasa 4/metabolismo , Regulación Enzimológica de la Expresión Génica , Incretinas/metabolismo , Hígado/enzimología , Neuropéptidos/metabolismo , Obesidad/enzimología , Animales , Dipeptidil Peptidasa 4/genética , Hígado Graso/enzimología , Técnica del Anticuerpo Fluorescente , Masculino , Ratas , Ratas Wistar , Ratas Zucker
7.
Eur J Histochem ; 55(1): e5, 2011 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-21556120

RESUMEN

Biliary complications often lead to acute and chronic liver injury after orthotopic liver transplantation (OLT). Bile composition and secretion depend on the integrated action of all the components of the biliary tree, starting from hepatocytes. Fatty livers are often discarded as grafts for OLT, since they are extremely vulnerable to conventional cold storage (CS). However, the insufficiency of donors has stimulated research to improve the usage of such marginal organs as well as grafts. Our group has recently developed a machine perfusion system at subnormothermic temperature (20°C; MP20) that allows a marked improvement in preservation of fatty and even of normal rat livers as compared with CS. We sought to evaluate the response of the biliary tree of fatty liver to MP20, and a suitable marker was essential to this purpose. Alkaline phosphatase (AlkP, EC 3.1.3.1), frequently used as marker of membrane transport in hepatocytes and bile ducts, was our first choice. Since no histochemical data were available on AlkP distribution and activity in fatty liver, we have first settled to investigate AlkP activity in the steatotic liver of fatty Zucker rats (fa/fa), using as controls lean Zucker (fa/+) and normal Wistar rats. The AlkP reaction in Wistar rats was in accordance with the existing data and, in particular, was present in bile canaliculi of hepatocytes in the periportal region and midzone, in the canals of Hering and in small bile ducts but not in large bile ducts. In lean ZR liver the AlkP reaction in Hering canals and small bile ducts was similar to Wistar rat liver but hepatocytes had lower canalicular activity and besides presented moderate basolateral reaction. The difference between lean Zucker and Wistar rats, both phenotypically normal animals, could be related to the fact that lean Zucker rats are genotypically heterozygous for a recessive mutated allele. In fatty liver, the activity in ductules and small bile ducts was unchanged, but most hepatocytes were devoid of AlkP activity with the exception of clusters of macrosteatotic hepatocytes in the mid-zone, where the reaction was intense in basolateral domains and in distorted canaliculi, a typical pattern of cholestasis. The interpretation of these data was hindered by the fact that the physiological role of AlkP is still under debate. In the present study, the various functions proposed for the role of the enzyme in bile canaliculi and in cholangiocytes are reviewed. Independently of the AlkP role, our data suggest that AlkP does not seem to be a reliable marker to study the initial step of bile production during OLT of fatty livers, but may still be used to investigate the behaviour of bile ductules and small bile ducts.


Asunto(s)
Fosfatasa Alcalina/metabolismo , Hígado/enzimología , Animales , Hígado Graso/enzimología , Inmunohistoquímica , Masculino , Obesidad/enzimología , Ratas , Ratas Wistar , Ratas Zucker
8.
Folia Morphol (Warsz) ; 67(4): 261-6, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19085866

RESUMEN

The axillary arch is the main variation of the axillary muscle. It was first described by Ramsay in 1795. In its classical form, it arises from the latissimus dorsi muscle and extends from this towards the pectoralis major, crossing the base of the axilla and creating a close relationship with the elements of the axillary neurovascular bundle. We describe the finding of 9 axillary arches, including one case of a bilateral arrangement. We develop a searching and finding technique for the axillary arch, essential for the safe and successful development of surgical procedures in the axillary region. Knowledge of this muscle variation and the possibility of finding it during axillary procedures is crucial for lymph node staging and lymphadenectomy and is also important for differential diagnosis in compressive pathologies of the axillary vessels and brachial plexus.


Asunto(s)
Axila/anatomía & histología , Músculo Esquelético/anatomía & histología , Adulto , Cadáver , Disección/métodos , Lateralidad Funcional , Humanos
9.
Eur J Vasc Endovasc Surg ; 33(4): 453-60, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17196848

RESUMEN

OBJECTIVES: Arteriographic lesions of diabetic subjects with critical limb ischemia (CLI) and ischemic foot ulcer were reviewed retrospectively, to provide new criteria for stratification of these patients on the basis of their vascular involvement. PATIENTS: In 417 consecutive CLI diabetic subjects with ischemic foot ulcer undergoing lower limb angiography, lesions were defined as stenosis or occlusion, localization, and length (<5 cm, 5-10 cm, >10 cm). In a subgroup of 389 subjects, foot arteries also were evaluated. Patients then were categorized into 7 classes of progressive vascular involvement based on angiographic findings. RESULTS: Of the 2893 found lesions (55% occlusions) 1% were in the iliac arteries, whereas 74% were in below-the-knee (BTK) arteries. Sixty-six % of all BTK lesions were occlusions, and 50% were occlusions >10 cm (p<0.001 vs proximal segments). Occlusions of all BTK were present in 28% of patients, although there was patency of at least one foot artery in 55% of patients. The morphologic Class 4 (two arteries occluded and multiple stenoses of tibial/peroneal and/or femoral/popliteal vessels) was the most common (36%). An inverse correlation between morphologic class and TcPO2 was observed (r=-0.187, p=0.003). CONCLUSIONS: In CLI diabetic subjects with ischemic foot ulcer, the vascular involvement is extremely diffuse and particularly severe in tibial arteries, with high prevalence of long occlusions. A new morphologic categorization of these patients is proposed.


Asunto(s)
Angiografía de Substracción Digital , Arteriopatías Oclusivas/diagnóstico por imagen , Pie Diabético/diagnóstico por imagen , Isquemia/diagnóstico por imagen , Extremidad Inferior/irrigación sanguínea , Anciano , Anciano de 80 o más Años , Arteriopatías Oclusivas/epidemiología , Arteriopatías Oclusivas/fisiopatología , Enfermedad Crónica , Constricción Patológica/diagnóstico por imagen , Complicaciones de la Diabetes/diagnóstico por imagen , Pie Diabético/epidemiología , Pie Diabético/fisiopatología , Femenino , Arteria Femoral/diagnóstico por imagen , Humanos , Arteria Ilíaca/diagnóstico por imagen , Isquemia/epidemiología , Isquemia/fisiopatología , Italia/epidemiología , Masculino , Persona de Mediana Edad , Arteria Poplítea/diagnóstico por imagen , Prevalencia , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Grado de Desobstrucción Vascular
10.
Biomed Pharmacother ; 60(5): 227-32, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16757146

RESUMEN

In this study we observed the effects in vivo of hyperthermic treatment on the cell kinetics (cell proliferation/cell death) in one case of human non-Hodgkin lymphoma, by analyzing the following morpho-cytochemical parameters: Acridine Orange fluorochromasia, mitotic index, proliferating cell nuclear antigen (PCNA) expression, terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) labeling, and ultrastructure morphology. After two hyperthermic exposures there was a significant reduction of cell growth rate (e.g. mitotic and PCNA positive cells) and an increase in cell loss by death. The cell death occurred by the typical apoptotic cascade, namely DNA fragmentation, chromatin hypercondensation and margination, karyorrhexis, ribonucleoproteins segregation and cytoplasm cleavage; in addition some necrotic cells were found. The data indicates that the hyperthermic treatments limit the cell proliferation (e.g. arrest and/or deceleration of the cell cycle) by facilitating the trigger of programmed cell death. It was concluded that thermal injury can be considered an effective inducer of antiproliferative and apoptogenic associated effects on the growth of this kind of neoplasia.


Asunto(s)
Hipertermia Inducida , Linfoma no Hodgkin/terapia , Apoptosis/efectos de los fármacos , Recuento de Células , Muerte Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Terapia Combinada , Fragmentación del ADN , ADN de Neoplasias/biosíntesis , ADN de Neoplasias/genética , Humanos , Inmunohistoquímica , Etiquetado Corte-Fin in Situ , Cinética , Linfoma no Hodgkin/tratamiento farmacológico , Linfoma no Hodgkin/patología , Masculino , Microscopía Electrónica de Transmisión , Microscopía Fluorescente , Persona de Mediana Edad , Mitosis/efectos de los fármacos , Recurrencia Local de Neoplasia , Antígeno Nuclear de Célula en Proliferación/metabolismo , ARN Neoplásico/biosíntesis , ARN Neoplásico/genética
11.
Histol Histopathol ; 18(1): 49-54, 2003 01.
Artículo en Inglés | MEDLINE | ID: mdl-12507283

RESUMEN

The purpose of this study was to investigate the toxicity of styrene in the liver of adult rats treated either by inhalation of styrene vapour (300 ppm, 6 h/d, 5 d/wk, for 2 wk) or intraperitoneally with different styrene doses (4, 40, 400 mg/Kg) for 3 consecutive days. Using a light microscope, some alterations of liver parenchyma and sinusoid dilation were noticed, more marked in the group treated with the intraperitoneal administration of the chemical. Using an electron microscope, some additional changes were observed (once again, more marked in the latter group of rats): a) an increase in the content of lipids inside hepatocytes, and b) the rise of intracytoplasmic, intercellular and perisinusoidal collagen fibres. Therefore, cell damage and functional disturbance of sinusoids due to perisinusoidal fibrosis are apparent in the liver of both groups of rats exposed to styrene treatment, but these changes are definitely more significant in those subjected to intraperitoneal administration.


Asunto(s)
Hígado/efectos de los fármacos , Hígado/patología , Estireno/toxicidad , Administración por Inhalación , Animales , Inyecciones Intraperitoneales , Hígado/ultraestructura , Masculino , Microscopía Electrónica , Ratas , Ratas Sprague-Dawley , Estireno/administración & dosificación
12.
Ital J Anat Embryol ; 106(2 Suppl 1): 295-302, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11729968

RESUMEN

In the liver of adult mice bearing an Ehrlich carcinoma on the leg, progressively hypoxic and displaying reactive hepatitis but not metastatic dissemination, extramedullary hemopoiesis was detected. Electron microscopy revealed mainly erythropoietic islands and scattered megakaryocytes in maturation stages up to the platelet-releasing phase. Erythropoietic cells expressed an embryonic-type of hemoglobin, which is more adequate to oxygenate hypoxic environments than the adult type. They were positive for the peroxidase reaction due to the presence of hemoglobin and could furthermore be visualized by the blue-excited red autofluorescence of protoporphyrin IX. Extramedullary hemopoiesis, one of the various examples of reactivation of fetal features in the liver associated with carcinogenesis, is supposed to be compensatory for the loss of blood cells induced by the tumor. Reviewing this process has the purpose of raising the question whether the fetal features are better adapted than adult ones to the metabolic and physiological characteristics of a tumor-influenced organism.


Asunto(s)
Carcinoma de Ehrlich/sangre , Hematopoyesis Extramedular/fisiología , Hemoglobinas/metabolismo , Hígado/patología , Hígado/fisiopatología , Síndromes Paraneoplásicos/sangre , Síndromes Paraneoplásicos/patología , Animales , Carcinoma de Ehrlich/fisiopatología , División Celular/fisiología , Eritrocitos/metabolismo , Eritrocitos/patología , Eritrocitos/ultraestructura , Células Precursoras Eritroides/metabolismo , Células Precursoras Eritroides/patología , Células Precursoras Eritroides/ultraestructura , Femenino , Feto/metabolismo , Feto/patología , Feto/ultraestructura , Hepatitis/etiología , Hepatitis/patología , Hepatitis/fisiopatología , Hepatocitos/metabolismo , Hepatocitos/patología , Hepatocitos/ultraestructura , Hipoxia/sangre , Hipoxia/etiología , Hipoxia/fisiopatología , Inmunohistoquímica , Hígado/ultraestructura , Ratones , Microscopía Electrónica , Síndromes Paraneoplásicos/fisiopatología
13.
Biomed Pharmacother ; 55(3): 170-3, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11325215

RESUMEN

We have analyzed by morphological (TEM) and histochemical (TUNEL reaction) criteria the type of cell death occurring in one case of human multiple myeloma after hyperthermia. Samples of cells examined immediately at the end of two treatments with a 15-day interval showed a significant degeneration, mostly demonstrating features of apoptosis (cell shrinkage, DNA fragmentation, karyorrhexis). The possible causes of the lag period between heating and apoptosis onset-expression are discussed.


Asunto(s)
Apoptosis/fisiología , Hipertermia Inducida , Mieloma Múltiple/terapia , Anciano , Fragmentación del ADN , Humanos , Etiquetado Corte-Fin in Situ , Masculino , Microscopía Electrónica , Mieloma Múltiple/patología , Mieloma Múltiple/ultraestructura
14.
J Anat ; 195 ( Pt 1): 19-25, 1999 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10473289

RESUMEN

The amount/distribution of liver melanin in 3 amphibian species (Rana esculenta, Triturus a. apuanus, Triturus carnifex) was studied during 2 periods of the annual cycle (summer activity-winter hibernation) by light and electron microscopy, image analysis and microspectrofluorometry. The increase in liver pigmentation (melanin content) during winter appeared to be correlated with morphological and functional modifications in the hepatocytes, which at this period were characterised by a decrease in metabolic activity. These findings were interpreted according to the functional role (e.g. phagocytosis, cytotoxic substance inactivation) played by the pigment cell component in the general physiology of the heterothermic vertebrate liver and, in particular, in relation to a compensatory engagement of these cells against hepatocellular hypoactivity during the winter period.


Asunto(s)
Anfibios/fisiología , Hibernación/fisiología , Hígado/fisiología , Pigmentación/fisiología , Estaciones del Año , Anfibios/metabolismo , Animales , Procesamiento de Imagen Asistido por Computador , Hígado/citología , Hígado/metabolismo , Macrófagos/química , Macrófagos/metabolismo , Masculino , Melaninas/análisis , Microscopía Electrónica , Rana esculenta/metabolismo , Rana esculenta/fisiología , Espectrometría de Fluorescencia , Triturus/metabolismo , Triturus/fisiología
15.
Anticancer Res ; 17(1A): 165-72, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9066647

RESUMEN

The tumor interstitial fluid (TIF) is a fluid phase present in the extracellular space of all tumors whose importance in oncology is seldom recognized. In order to stimulate other researchers to give it the due importance, a review of the available data (including our own) is provided. An hypothesis is presented for the genesis, fate and role of the TIF in the processes of invasion, growth and metastatization. Open questions regarding the TIF's role in tumor response to therapy are raised.


Asunto(s)
Espacio Extracelular/fisiología , Neoplasias/patología , Animales , Humanos , Necrosis , Invasividad Neoplásica , Metástasis de la Neoplasia , Neoplasias/terapia
16.
Anticancer Res ; 17(6D): 4713-6, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9494594

RESUMEN

Using ultrastructural analysis, we studied the effects of hyperthermic treatment of one case of human liver metastasis from colon carcinoma. The results indicate that the main hyperthermic response involves the neoplastic and the histiocytic cell population. The drastic decrease in metastatic cells was accompanied by the appearance of cell fragments and apoptotic bodies. Consequently, the histiocytic component (Kupffer cells) showed increased frequency, indicating an activated state. The data are consistent with a direct action of the heat on tumor cells with subsequent activation of Kupffer cells.


Asunto(s)
Neoplasias del Colon/terapia , Hipertermia Inducida , Neoplasias Hepáticas/secundario , Neoplasias Hepáticas/terapia , Apoptosis , Humanos , Macrófagos del Hígado/patología , Macrófagos del Hígado/ultraestructura , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/ultraestructura , Microscopía Electrónica , Terapia por Radiofrecuencia
17.
Anticancer Res ; 16(3B): 1491-502, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8694518

RESUMEN

Hypoxic tumor cells resist most therapies and cause tumor regrowth when their environment improves. Identifying the adaptation strategies to hypoxia would help develop better tailored cancer therapies. Ehrlich carcinomas implanted on mice were analyzed histochemically for the following enzyme activities: lactate, succinate and glucose-6-phosphate dehydrogenases, dihydrofolate reductase, purine nucleoside phosphorylase, xanthine oxidoreductase, and acid phosphatase. With the exception of xanthine oxidoreductase, which was not active in tumor cells, and of succinate dehydrogenase the activity of which was not significatively altered, all other activities were much higher in perinecrotic cells with respect to cells close to blood vessels. These data suggest the integration of metabolic paths allowing purine and lipid biosyntheses. Degradation products from the necrosis are presumed to be employed as surrogates of blood-borne nutritive substances by cells distant from the vascularization.


Asunto(s)
Carcinoma de Ehrlich/enzimología , Fosfatasa Ácida/metabolismo , Animales , Carcinoma de Ehrlich/patología , Femenino , Glucosafosfato Deshidrogenasa/metabolismo , L-Lactato Deshidrogenasa/metabolismo , Ratones , Necrosis , Purina-Nucleósido Fosforilasa/metabolismo , Tetrahidrofolato Deshidrogenasa/metabolismo
18.
Rev. argent. reumatol ; 7(2): 35-7, mayo 1996.
Artículo en Español | LILACS | ID: lil-172575

RESUMEN

La Centellografía Salival es un método sensitivo para la evaluación de las glándulas salivales.Ha sido descripta una correlación entre la centellografía salival,el flujo salival,la sialografía e histología.Nosotros realizamos un estudio prospectivo en 22 pacientes con Síndrome de Sjögren para confirmar el rol de la Centellografía Salival.En 14 pacientes la Centellografía mostró un patrón de captación anormal.La Centellografía mostró ser un método sensible para evaluar el compromiso glandular.No hubo correlación entre el patrón histológico y la duración de la enfermedad


Asunto(s)
Glándulas Salivales , Síndrome de Sjögren
19.
Rev. argent. reumatol ; 7(2): 35-7, mayo 1996.
Artículo en Español | BINACIS | ID: bin-22098

RESUMEN

La Centellografía Salival es un método sensitivo para la evaluación de las glándulas salivales.Ha sido descripta una correlación entre la centellografía salival,el flujo salival,la sialografía e histología.Nosotros realizamos un estudio prospectivo en 22 pacientes con Síndrome de Sj÷gren para confirmar el rol de la Centellografía Salival.En 14 pacientes la Centellografía mostró un patrón de captación anormal.La Centellografía mostró ser un método sensible para evaluar el compromiso glandular.No hubo correlación entre el patrón histológico y la duración de la enfermedad


Asunto(s)
Glándulas Salivales/diagnóstico por imagen
20.
Biomed Pharmacother ; 50(2): 79-84, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8761713

RESUMEN

The purpose of the present study was to evaluate by morphological approaches (light and electron microscopy), the effect of hyperthermic treatment in one case of human liver metastasis. The results demonstrate that hyperthermia causes a significant reduction of the metastatic cells circulating into sinusoids and the "normalization" of the hepatocytes substructure. The data are consistent with a direct and/or indirect action of the temperature on the presence of infiltrating tumor cells. Particular importance is attributed to a general activation of lysosomes present in neoplastic cells, Kupffer cells and hepatocytes.


Asunto(s)
Exocitosis , Hipertermia Inducida , Neoplasias Hepáticas/terapia , Lisosomas/fisiología , Muerte Celular , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/secundario , Microscopía , Microscopía Electrónica , Células Tumorales Cultivadas/patología
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