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1.
J Opt Soc Am A Opt Image Sci Vis ; 39(12): C21-C28, 2022 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-36520719

RESUMEN

A class of partially coherent spherical sources is introduced whose cross-spectral density across the surface has a modal expansion made up of spherical harmonics. For such sources, the solution of the propagation problem in all the outer spaces can be written through a series of the propagated modes, which maintains the spherical harmonic structure. The main features of this class of cross-spectral densities are derived illustrating their coherence properties with examples. Attention is paid to the properties of radial coherence. In particular, it is clearly shown that sources with perfect radial coherence exist with angular coherence that is only partial.

2.
Opt Lett ; 47(19): 5224-5227, 2022 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-36181227

RESUMEN

Partially coherent scalar sources with cylindrical symmetry radiating outwards are introduced. Homogeneous cross-spectral densities are shown to possess angularly modulated Hankel modes, whose amplitudes are subject to a filtering process during propagation. Simple criteria for treating such sources are given. For the case of an incoherent cylinder, the number of effective modes is found and spatial coherence is shown to appear in the radiated light. The radial coherence of the radiated field is then examined. Non-homogeneous cylindrical sources are also introduced.

3.
Cell Mol Life Sci ; 79(8): 437, 2022 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-35864382

RESUMEN

The neurodegenerative condition FENIB (familiar encephalopathy with neuroserpin inclusion bodies) is caused by heterozygous expression of polymerogenic mutant neuroserpin (NS), with polymer deposition within the endoplasmic reticulum (ER) of neurons. We generated transgenic neural progenitor cells (NPCs) from mouse fetal cerebral cortex stably expressing either the control protein GFP or human wild type, polymerogenic G392E or truncated (delta) NS. This cellular model makes it possible to study the toxicity of polymerogenic NS in the appropriated cell type by in vitro differentiation to neurons. Our previous work showed that expression of G392E NS in differentiated NPCs induced an adaptive response through the upregulation of several genes involved in the defence against oxidative stress, and that pharmacological reduction of the antioxidant defences by drug treatments rendered G392E NS neurons more susceptible to apoptosis than control neurons. In this study, we assessed mitochondrial distribution and found a higher percentage of perinuclear localisation in G392E NS neurons, particularly in those containing polymers, a phenotype that was enhanced by glutathione chelation and rescued by antioxidant molecules. Mitochondrial membrane potential and contact sites between mitochondria and the ER were reduced in neurons expressing the G392E mutation. These alterations were associated with a pattern of ER stress that involved the ER overload response but not the unfolded protein response. Our results suggest that intracellular accumulation of NS polymers affects the interaction between the ER and mitochondria, causing mitochondrial alterations that contribute to the neuronal degeneration seen in FENIB patients.


Asunto(s)
Antioxidantes , Neuronas , Animales , Antioxidantes/metabolismo , Antioxidantes/farmacología , Estrés del Retículo Endoplásmico , Epilepsias Mioclónicas , Trastornos Heredodegenerativos del Sistema Nervioso , Humanos , Ratones , FN-kappa B/metabolismo , Neuronas/metabolismo , Neuropéptidos , Polímeros , Serpinas , Neuroserpina
4.
Lymphology ; 51(2): 66-72, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30253457

RESUMEN

This study aimed to provide information on proprioception alterations in lymphedema-affected limbs. Blindfolded subjects sat at a table with their forearms positioned on paddles. The hinges of the paddles were aligned with the elbow joint and an electronic goniometer was positioned to measure the angle of the forearm. Paddles were moved by an electric servomotor with a slow angular speed that was barely appreciated by the subjects. Subjects were then asked to guess the position of the affected arm in comparison with the unaffected arm to study the position sense of the lymphedema-affected arm. The study investigated 50 women affected by secondary upper limb lymphedema by measuring the difference in terms of degrees of arch of movement in comparison with the unaffected arm and also both duration of lymphedema and the circumference of the forearm. Results were matched with a control group of 50 unaffected women providing proof of compromised proprioception in lymphedema-affected arms. In addition, results also showed a correlation with duration of lymphedema but not with size (stage) of the lymphedematous arm.


Asunto(s)
Brazo/fisiopatología , Linfedema/diagnóstico , Linfedema/fisiopatología , Propiocepción , Anciano , Femenino , Humanos , Persona de Mediana Edad , Índice de Severidad de la Enfermedad , Circunferencia de la Cintura
5.
Tech Coloproctol ; 21(2): 139-147, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28194568

RESUMEN

BACKGROUND: The aim of this study was to identify risk factors for lymph node positivity in T1 colon cancer and to carry out a surgical quality assurance audit. METHODS: The sample consisted of consecutive patients treated for early-stage colon lesions in 15 colorectal referral centres between 2011 and 2014. The study investigated 38 factors grouped into four categories: demographic information, preoperative data, indications for surgery and post-operative data. A univariate and multivariate logistic regression analysis was performed to analyze the significance of each factor both in terms of lymph node (LN) harvesting and LN metastases. RESULTS: Out of 507 patients enrolled, 394 patients were considered for analysis. Thirty-five (8.91%) patients had positive LN. Statistically significant differences related to total LN harvesting were found in relation to central vessel ligation and segmental resections. Cumulative distribution demonstrated that the rate of positive LN increased starting at 12 LN harvested and reached a plateau at 25 LN. CONCLUSIONS: Some factors associated with an increase in detection of positive LN were identified. However, further studies are needed to identify more sensitive markers and avoid surgical overtreatment. There is a need to raise the minimum LN count and to use the LN count as an indicator of surgical quality.


Asunto(s)
Neoplasias del Colon/patología , Detección Precoz del Cáncer/estadística & datos numéricos , Escisión del Ganglio Linfático/estadística & datos numéricos , Ganglios Linfáticos/patología , Metástasis Linfática/diagnóstico , Adulto , Anciano , Neoplasias del Colon/etiología , Neoplasias del Colon/cirugía , Detección Precoz del Cáncer/métodos , Femenino , Humanos , Modelos Logísticos , Ganglios Linfáticos/cirugía , Masculino , Auditoría Médica , Uso Excesivo de los Servicios de Salud/estadística & datos numéricos , Persona de Mediana Edad , Análisis Multivariante , Estadificación de Neoplasias , Estudios Retrospectivos , Factores de Riesgo
6.
Bull Entomol Res ; 106(1): 34-46, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26072670

RESUMEN

Establishing reliable methods for the identification of benthic chironomid communities is important due to their significant contribution to biomass, ecology and the aquatic food web. Immature larval specimens are more difficult to identify to species level by traditional morphological methods than their fully developed adult counterparts, and few keys are available to identify the larval species. In order to develop molecular criteria to identify species of chironomid larvae, larval and adult chironomids from Western Lake Erie were subjected to both molecular and morphological taxonomic analysis. Mitochondrial cytochrome c oxidase I (COI) barcode sequences of 33 adults that were identified to species level by morphological methods were grouped with COI sequences of 189 larvae in a neighbor-joining taxon-ID tree. Most of these larvae could be identified only to genus level by morphological taxonomy (only 22 of the 189 sequenced larvae could be identified to species level). The taxon-ID tree of larval sequences had 45 operational taxonomic units (OTUs, defined as clusters with >97% identity or individual sequences differing from nearest neighbors by >3%; supported by analysis of all larval pairwise differences), of which seven could be identified to species or 'species group' level by larval morphology. Reference sequences from the GenBank and BOLD databases assigned six larval OTUs with presumptive species level identifications and confirmed one previously assigned species level identification. Sequences from morphologically identified adults in the present study grouped with and further classified the identity of 13 larval OTUs. The use of morphological identification and subsequent DNA barcoding of adult chironomids proved to be beneficial in revealing possible species level identifications of larval specimens. Sequence data from this study also contribute to currently inadequate public databases relevant to the Great Lakes region, while the neighbor-joining analysis reported here describes the application and confirmation of a useful tool that can accelerate identification and bioassessment of chironomid communities.


Asunto(s)
Chironomidae/clasificación , Código de Barras del ADN Taxonómico , Animales , Chironomidae/anatomía & histología , Chironomidae/genética , Chironomidae/crecimiento & desarrollo , Complejo IV de Transporte de Electrones/genética , Complejo IV de Transporte de Electrones/metabolismo , Femenino , Proteínas de Insectos/genética , Proteínas de Insectos/metabolismo , Lagos , Larva/anatomía & histología , Larva/clasificación , Larva/genética , Larva/crecimiento & desarrollo , Masculino , Michigan , Datos de Secuencia Molecular , Ohio , Filogenia , Análisis de Secuencia de ADN , Especificidad de la Especie
7.
Clin Ter ; 166(6): e389-400, 2015.
Artículo en Italiano | MEDLINE | ID: mdl-26794822

RESUMEN

Phosphorus is an essential mineral in the regulation of many metabolic processes. However, is known as alterations in serum phosphate levels, compared to the normal range, have clinical relevance: many studies about phosphorus and cardiovascular risk have shown that high serum phosphate levels are associated with clinical and subclinical cardiovascular disease, in CKD and non-CKD patients. In recent years, serum phosphate level within the upper limits of normal range is also identified as a "stealthier killer", and has emerged as a risk factor of cardiovascular mortality and progression of CKD. This mounting evidence suggests the possibility that lowering serum phosphate levels may be a future target of cardiovascular disease management, also through the use of early biomarkers of phosphate overload, such as FGF23, Klotho or the urinary fractional excretion of phosphate. The goal must be an early diagnosis and treatment of disordered phosphorus metabolism, before end-organ damage occurs. Since the western diet is rich in phosphate, a dietary restriction associated with the use of phosphate binders, as well as the use of intervention such as calcitriol supplementation, certainly will have a positive influence on the phosphate-regulatory axis.


Asunto(s)
Enfermedades Cardiovasculares/etiología , Hiperfosfatemia/complicaciones , Biomarcadores/sangre , Enfermedades Cardiovasculares/sangre , Enfermedades Cardiovasculares/diagnóstico , Enfermedades Cardiovasculares/prevención & control , Progresión de la Enfermedad , Factor-23 de Crecimiento de Fibroblastos , Humanos , Hiperfosfatemia/diagnóstico , Hiperfosfatemia/terapia , Fosfatos/sangre , Insuficiencia Renal Crónica/sangre , Insuficiencia Renal Crónica/complicaciones , Factores de Riesgo
8.
Minerva Med ; 104(1): 85-91, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23392541

RESUMEN

AIM: Cells involved in atherogenesis produce growth factors crucial for the progression of the atherosclerotic lesions. One of them is the heparin-binding EGF-like growth factor (HB-EGF), a member of the epidermal growth factor (EGF) family, synthesized as a transmembrane precursor (proHB-EGF). This anchored insoluble juxtacrine growth factor can be converted into a soluble molecule with paracrine activity and mature HB-EGF is released in the extracellular matrix from the cell surface. HB-EGF is a potent stimulator of cell proliferation, migration and cell motility and several studies show that HB-EGF is associated with pathologies of hyperplasia of smooth muscle cells including atherosclerosis. METHODS: We localized HB-EGF by immunohistochemistry within the atherosclerotic lesions collected from right or left internal carotid artery of 20 patients with evident clinical symptoms. RESULTS: In the 20 samples we tested, the proportion of positive samples was significant. Considering the only positive samples the proportion difference related to the gender of patients was highly significant. CONCLUSION: The aim of our investigation was to better understand if this growth factor exerts its role through a juxtacrine or paracrine mechanism, or both in the process of atherogenesis. According to the results, the paracrine role of HB-EGF was clear.


Asunto(s)
Aterosclerosis/metabolismo , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Anciano , Aterosclerosis/etiología , Aterosclerosis/patología , Biomarcadores/análisis , Biomarcadores/metabolismo , Femenino , Factor de Crecimiento Similar a EGF de Unión a Heparina , Humanos , Inmunohistoquímica , Péptidos y Proteínas de Señalización Intercelular/análisis , Masculino
9.
Clin Ter ; 160(6): 435-9, 2009.
Artículo en Italiano | MEDLINE | ID: mdl-20198283

RESUMEN

AIMS: Heparin-binding epidermal growth factor is a member of the EGF family, it is a potent mitogen for smooth muscle cells and has been implicated in atherosclerosis, angiogenesis. In athererogenesis, HB-EGF has been detected in medial smooth cells and foamy macrofages. In this work, we have investigate about immunohistocemical localization of HB-EGF in atherosclerotic plaques. MATERIALS AND METHODS: Three cases of man affected by atherosclerosis have been examined. We have collected and examined atherosclerotic plaques by immunohistochemical procedure in optical microscopy. Samples have been incubated with primary Ac (anti-human HB-EGF- goat IgG). RESULTS: In the three examined cases, results are partly overlap-ping, but with some difference in relation to location of positivity to HB-EGF. Only in one case, HB-EGF staining is rather weak and located just below endothelium where is a thickened area of tissue rich in fibres and few cells, In another case, positivity to HB-EGF is present in an area of connective tissue of the intima. In the last case, positivity to HB-EGF is evident in the context of a presumed elastic tissue with fusiform cells following fibres orientation, and that could be fibroblasts or smooth muscle cells. CONCLUSIONS: These results indicate that HB-EGF is involved in the development of atherosclerotic plaques and that HB-EGF is a possible target for atherosclerosis therapy.


Asunto(s)
Péptidos y Proteínas de Señalización Intercelular/análisis , Placa Aterosclerótica/patología , Anciano , Factor de Crecimiento Similar a EGF de Unión a Heparina , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad
10.
Clin Ter ; 159(2): 111-6, 2008.
Artículo en Italiano | MEDLINE | ID: mdl-18463770

RESUMEN

Heparin-Binding Epidermal Growth Factor (HB-EGF) is growth factor member of EGF family that stimulate differentiation and growth. HB-EGF was initially identified as a secreted product of human macrophage-like cells, it is sinthetized as a transmembrana protein; proHB-EGF; that is shed by specific metalloproteases, releasing soluble growth factor(sHB-EGF). It exerts biological activity trough activation of the EGFR. sHB-EGF is implicated in diverse biological processes: angiogenesis, shin wound, blastocysts implantation, atherosclerosis, tumor formation moreover it acts as the Diphtheria Toxin (DT) receptor. HB-EGF It's an important molecule because could be a novel targeting for cancer and atherosclerosis therapy.


Asunto(s)
Péptidos y Proteínas de Señalización Intercelular/fisiología , Animales , Aterosclerosis/tratamiento farmacológico , Aterosclerosis/fisiopatología , Transformación Celular Neoplásica , Resistencia a Medicamentos/fisiología , Implantación del Embrión/fisiología , Receptores ErbB/fisiología , Factor de Crecimiento Similar a EGF de Unión a Heparina , Humanos , Péptidos y Proteínas de Señalización Intercelular/química , Péptidos y Proteínas de Señalización Intercelular/uso terapéutico , Ratones , Mitosis/fisiología , Metástasis de la Neoplasia , Neovascularización Fisiológica/fisiología , Estructura Terciaria de Proteína , Ratas , Receptor ErbB-4 , Regeneración/fisiología , Cicatrización de Heridas/fisiología
11.
J Microsc ; 229(Pt 2): 337-43, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18304095

RESUMEN

We demonstrate a novel optical method for characterizing single Au nanoparticles by acquiring their scattering patterns. This technique combines confocal microscopy and higher-order laser modes for detecting the light scattered by sub-wavelength-sized nanoobjects. The optical patterns are generated by the coherent superposition of the field scattered by individual metallic particles and the excitation field reflected at the cover slide-air interface and provide information about the particles' position, orientation, size and shape. Detectable changes in the full width at half maximum (FWHM) of the signal intensity permit to distinguish between 20- and 60-nm diameter Au spheres. The confocal images are also very sensitive to the particle's geometry and polarizability, that is, Au nanospheres, Au nanorods and triangular Au nanoplates give different characteristic patterns if the excitation wavelength is varied.

12.
Clin Ter ; 158(6): 519-22, 2007.
Artículo en Italiano | MEDLINE | ID: mdl-18265718

RESUMEN

The pituitary gland and infundibulum can be involved in a variety of medical conditions, including infiltrative diseases, fungal infections, tuberculosis, primary and metastatic tumors. Metastases to the pituitary gland are absolutely rare, and they are generally secondary to pulmonary carcinoma in men and breast carcinoma in women. Pituitary metastases more commonly affect the posterior lobe and the infundibulum than the anterior lobe. The posterior lobe involvement may explain why patients with pituitary metastases frequently present with diabetes insipidus. We are presenting a case report of a 48-year-old male patient with sudden onset of polyuria and persistent thirst. Laboratory results revealed central diabetes insipidus. Computed tomography (CT) scan of the brain showed a mass located in the sella turcica and suprasellar region. CT scan of the chest showed a mass in the right superior lobe with mediastinal lymphadenopathy. Bronchoscopy and biopsy demonstrated a pulmonary adenocarcinoma. Thus, we made a diagnosis of lung cancer with local and pituitary metastases. The patient received radiotherapy on the pituitary gland and adjuvant chemotherapy. As a result the intrasellar and suprasellar mass decreased in size and urinary output accordingly decreased. In conclusion, in patients presenting with sudden onset of diabetes insipidus pituitary metastases should be taken in account in differential diagnosis.


Asunto(s)
Adenocarcinoma/diagnóstico , Diabetes Insípida/etiología , Neoplasias Pulmonares/diagnóstico , Neoplasias Hipofisarias/complicaciones , Neoplasias Hipofisarias/secundario , Adenocarcinoma/secundario , Biopsia , Broncoscopía , Diabetes Insípida/complicaciones , Diagnóstico Diferencial , Humanos , Neoplasias Pulmonares/patología , Metástasis Linfática , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Poliuria/etiología , Sed , Tomografía Computarizada por Rayos X
13.
J Biomed Opt ; 6(3): 292-9, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11516319

RESUMEN

During the last years, measurements considerably beyond the conventional "Abbe-Limit" of optical resolution in far field light microscopy were realized by several light microscopical approaches. Point spread function (PSF) engineering, spectral precision distance microscopy (SPDM), and related methods were used to demonstrate the feasibility of such measurements. SPDM allows the measurement of position and multiple distances between point-like fluorescent objects of different spectral signatures far below the optical resolution criterion as defined by the full width at half maximum of the PSF. Here, we report a software method to obtain online visualization of light distribution in the lateral and axial direction of any object detected in a spatially modulated illumination (SMI) microscope. This strongly facilitates routine application of SMI microscopy. The software was developed using Microsoft Visual C++ running on Windows NT. Furthermore, some aspects of the theoretical limits of the SPDM method were studied by virtual microscopy. For the case of SMI microscopy the precision of axial distance measurements was studied, taking into account photon statistics and image analysis procedures. The results indicate that even under low fluorescence intensity conditions typical for biological structure research, precise distance measurements in the nanometer range can be determined, and that axial distances in the order of 40 nm are detectable with such precision.


Asunto(s)
Procesamiento de Imagen Asistido por Computador , Microscopía de Polarización/métodos , Microscopía de Polarización/normas , Simulación por Computador , Predicción , Rayos Láser , Microscopía de Polarización/instrumentación , Programas Informáticos , Interfaz Usuario-Computador
17.
Minerva Cardioangiol ; 44(1-2): 33-7, 1996.
Artículo en Italiano | MEDLINE | ID: mdl-8767620

RESUMEN

In a controlled study of 100 patients, mean age 65 years old, suffering from chronic peripheral obliterative arterial disease, Leriche's stage II, were randomised in two groups treated respectively with defibrotide (400 mg bid) or heparan-sulfate (40 mg bid) by the oral route for a period of 6 months. At basal and after 30, 90 and 180 treatment days, patients were assessed for pain, paresthesias, rigidity and or tiredness in the leg, Winsor index (WI) relative and absolute walking distance (RWD, AWD), and time of recovery from pain. In order to evaluate microcirculation the following parameters were tested: resting flow (RF), standing flow (SF), veno-arteriolar reflex (VAR) and a capillaroscopy study was conducted. All patients showed an improvement in the clinical and instrumental parameters but more pronounced in the defibrotide group; the difference between the beginning and the end of the therapy was significantly better for defibrotide (p < 0.01). The tolerability observed was good, no side-effects were reported during the study.


Asunto(s)
Arteriopatías Oclusivas/tratamiento farmacológico , Fibrinolíticos/uso terapéutico , Heparitina Sulfato/uso terapéutico , Pierna/irrigación sanguínea , Inhibidores de Agregación Plaquetaria/uso terapéutico , Polidesoxirribonucleótidos/uso terapéutico , Adulto , Anciano , Arteriopatías Oclusivas/diagnóstico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores de Tiempo
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