Hubert van den Bergh

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From lidar signals detected with a shot/shot differential absorption lidar instrument tuned for tropospheric O3 measurements and recording each individual return, histograms of their sampled values for each channel of their digitizers were reconstructed. Anal. of their shape permits correction of measurements for exptl. biases. In particular, a neg. correlation was obsd. between the histogram skew and the intensity of backscattered light. The skew comes from a tail at high sampled values, interpreted as due

The timing has been optimized of photodetection (and possibly also phototherapy) of early cancer in the upper aerodigestive tract and bronchi and the relative concn. of fluorescent components of Photofrin II measured in patients as a function of the time after i.v. injection. In most cases, the measurements have been made on the tumor, neighboring normal tissue, and distant skin. The obsd. kinetics will be correlated in the future, among other parameters, with the staging of the early cancer, in particular,

Purpose: The present study was initiated to det. the conditions under which a single photodynamic treatment would induce maximal damage to a tumor with no or at least minimal reversible damage to a normal striated muscle. Methods and Materials: The techniq ...

Although the versatility of photodynamic therapy (PDT) is well established, the technical aspects of light delivery systems vary significantly depending on the targeted organ. This article describes the optical properties of a light and drug delivery syste ...

The changes in the autofluorescence characteristics of the bronchial tissue is of crucial interest as a cancer diagnostic tool. Evidence exists that this native fluorescence or autofluorescence of bronchial tissues changes when they turn dysplastic and to ...

Autofluorescence is emerging as a useful tool for the detection of early cancers in the bronchi. It has already produced interesting results, which have been implemented in commercial imaging devices. Their design relies on the spectroscopy of the tissues ...

Light propagation in two-layered turbid media having an infinitely thick second layer is investigated in the steady-state, frequency, and time domains. A solution of the diffusion approximation to the transport equation is derived by employing the extrapol ...

We describe a new fluorescence imaging device for clinical cancer photodetection in hollow organs in which the image contrast is derived from the fluorescence lifetime of the fluorochrome at each point in a 2D image. Lifetime images are created from a series of images obtained from two gain-modulated image intensifiers. One of them (II-1) detects the light-induced tissue fluorescence, whereas the other (II-2) detects the backscattered fluorescence excitation light. This light is modulated at the same freque

SF6 in a free jet was vibrationally excited by a continuous-wave CO2 laser. The subsequent energy transfer processes, in which vibrational energy is degraded, lead to changes in the beam's spatial, velocity and cluster-size distributions. These changes were obsd. by mass-spectrometric techniques. The laser-induced perturbations of the free jet depend strongly on the location at which the laser beam is focused on the SF6 free jet. The largest perturbations were obsd. on irradn. close to the nozzle exit. Meas

The authors have recently shown that immunophotodetection of human colon carcinomas in nude mice and in patients is possible by using anti-carcinoembryonic antigen monoclonal antibodies (MAb) coupled to fluorescein. The most common clin. application of pho ...

Acute coronary syndrome is a life-threatening condition of utmost clinical importance, which, despite recent progress in the field, is still associated with high morbidity and mortality. Acute coronary syndrome results from a rupture or erosion of vulnerab ...

A 49-year-old man with the idiopathic hypereosinophilic syndrome (HES) and a unique chromosomal abnormality 46,XY,t(5;9)(q32;q33) is reported. Complete cytogenetic remission was induced by interferon alpha-2b (IFN-alpha). The beneficial action of IFN-alpha in different stem-cell disorders such as CML, HES, multiple myeloma and solid tumours such as hypernephroma or malignant melanoma suggests a common regulatory effect possibly by immunomodulation or other (immune-mediated) mechanisms, but the exact pathoph

The prognosis of superficial bladder cancer in terms of recurrence and disease progression is related to the bladder tumor multiplicity and the presence of concomitant 'plane' tumors such as high grade dysplasia and carcinoma in situ (CIS). This study on 33 patients tries to demonstrate the interest of fluorescence cystoscopy in transurethral resection of superficial bladder cancer The method is based on the detection of the protoporphyrin IX (PpIX) induced fluorescence in urothelial cancer cells by topical

Several parameters affect clin. trials in photodynamic therapy and influence the therapeutic outcome. Beside drug dose, light dose, drug-light interval and other variables, the fluence rate is a parameter that can influence the therapeutic results. In this ...

OBJECTIVE: To evaluate the safety and short-term visual and fluorescein angiographic effects of a single photodynamic therapy treatment with verteporfin with the use of different dosage regimens in patients with choroidal neovascularization (CNV) from age-related macular degeneration. DESIGN: Nonrandomized, multicenter, open-label, clinical trial using 5 dosage regimens. SETTING: Four ophthalmic centers in North America and Europe providing retinal care. PARTICIPANTS: Patients with subfoveal CNV caused by a

The sepn. was demonstrated by studying the IR multiphoton dissocn. of CF2DCl [1495-14-3] and CF2HCl/CF2DCl mixts. It is shown how the parameters which control the IR photochem. of CF2DCl such as the temp. and the pressure, as well as the wavelength, the energy fluence and the intensity of the laser pulse, can be optimized for D sepn. IR anal. of the disappearing CF2DCl and CF2HCl peaks indicates isotopic selectivities in excess of 104. Dissocn. yields of up to 5% are obsd. at fluences around 6 J cm-2 with 3

Targeted angiostatic therapy receives major attention for the treatment of cancer and exudative age-related macular degeneration (AMD). Photodynamic therapy (PDT) has been used as an effective clinical approach for these diseases. Since PDT can cause an an ...

Time-resolved measurements of endogenous tissue autofluorescence were carried out on the bronchial mucosa of 18 patients during endoscopy by the means of an optical fibre-based spectrometer. The objective was to assess the fluorescence lifetime as a new contrast parameter between normal and malignant tissue and to explain the origin of a previously observed contrast in fluorescence intensity. The intra- and interpatient variation of tissue autofluorescence intensity and decay on normal tissue was determined

In vivo spectrofluorometric analysis represents a tool to obtain information about fluorophore distribution in tissue. Based on a Peltier-cooled CCD we designed a fluorescence excitation and emission spectrograph which allows to obtain tissue spectra endoscopically and in a clinical environment. Clinical studies were performed on patients with positive cytology or tumor recurrence in the urinary bladder. Patients received a 50 ml instillation of 3% ALA solution at pH 5.5 during 3 to 4 hours and underwent a

This paper concerns an evaluation of ozone (O-3) and planetary boundary layer (PBL) dynamics over the complex topography of the Grenoble region through a combination of measurements and mesoscale model (METPHOMOD) predictions for three days, during July 1999. The measurements of O-3 and PBL structure were obtained with a Differential Absorption Lidar ( DIAL) system, situated 20 km south of Grenoble at Vif (310m ASL). The combined lidar observations and model calculations are in good agreement with atmospher

Hubert van den Bergh

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Correction scheme for experimental biases in differential absorption lidar tropospheric ozone measurements based on the analysis of shot per shot data samples

Photofrin II pharmacokinetics and optical dosing in tissue: apparatus and clinical measurements for the pharynx, esophagus, and tracheobronchial tree

Interstitial photodynamic therapy with tetra(m-hydroxyphenyl)chlorin: tumor versus striated muscle damage

Optical Characterization of an Intra-Arterial Light and Drug Delivery System for Photodynamic Therapy of Atherosclerotic Plaque

In vivo autofluorescence imaging of early cancers in the human tracheobronchial tree with a spectrally optimized system

Absolute autofluorescence spectra of human healthy, metaplastic, and early cancerous bronchial tissue in vivo

Noninvasive determination of the optical properties of two-layered turbid media

Endoscopic frequency-domain fluorescence lifetime imaging for clinical cancer photodetection: apparatus design

Infrared laser action on the spatial, velocity, and cluster-size distributions in a sulfur hexafluoride free jet

Antibody-indocyanin conjugates for immunophotodetection of human squamous cell carcinoma in nude mice

Photodynamic therapy for the treatment of atherosclerotic plaque: Lost in translation?

Further evidence for the clonal nature of the idiopathic hypereosinophilic syndrome: complete haematological and cytogenetic remission induced by interferon-alpha in a case with a unique chromosomal abnormality

Fluorescence photodetection of urothelial neoplastic foci in superficial bladder cancer

In-vivo fluence rate effect in photodynamic therapy of early cancers with tetra(m-hydroxyphenyl)chlorin

Photodynamic therapy with verteporfin for choroidal neovascularization caused by age-related macular degeneration: results of a single treatment in a phase 1 and 2 study

Deuterium separation and infrared photochemistry in chlorodifluoromethane (CF2HCl)

Angiostatic kinase inhibitors to sustain photodynamic angio-occlusion

Time-resolved autofluorescence spectroscopy of the bronchial mucosa for the detection of early cancer: Clinical results

Fluorescence excitation and emission spectra of ALA-induced protoporphyrin IX in normal and tumoral tissue of the human bladder

An investigation of ozone and planetary boundary layer dynamics over the complex topography of Grenoble combining measurements and modeling