Ervin J. Fenyves

Effects of toxic exposure to molds and mycotoxins in building-related illnesses.

The authors studied 100 patients who had been exposed to toxic molds in their homes. The predominant molds identified were Alternaria, Cladosporium, Aspergillus, Penicillium, Stachybotrys, Curvularia, Basidiomycetes, Myxomycetes, smuts, Epicoccus, Fusarium, Bipolaris, and Rhizopus. A variety of tests were performed on all, or on subgroups of, these patients. Sensitivities and exposures were confirmed in all patients by intradermal skin testing for individual molds (44–98% positive), and by measurement of serum antibodies. Abnormalities in T and B cells, and subsets, were found in more than 80% of the patients. The findings of trichothecene toxin and breakdown products in the urine, serum antibodies to molds, and positive intradermal skin tests confirmed mycotoxin exposure. Respiratory signs (e.g., rhinorrhea, sinus tenderness, wheezing) were found in 64% of all patients, and physical signs and symptoms of neurological dysfunction (e.g., inability to stand on the toes or to walk a straight line with eyes closed, as well as short-term memory loss) were identified in 70% of all patients. Objective abnormal autonomic nervous system tests were positive in all 100 patients tested. Brain scans, conducted using triple-head single photon emission computed tomography, were abnormal in 26 (86%) of 30 (subgroup of the 100) patients tested. Objective neuropsychological evaluations of 46 of the patients who exhibited symptoms of neurological impairment showed typical abnormalities in short-term memory, executive function/judgment, concentration, and hand/eye coordination.

Reduction of Chemical Sensitivity by Means of Heat Depuration, Physical Therapy and Nutritional Supplementation in a Controlled Environment

Patients with chemical sensitivity were treated in heat depuration physical therapy units and housed in living facilities, both of which were specially constructed so they were less chemically polluted. Rotary diets of less chemically contaminated water and food were consumed. Two hundred and ten chemically sensitive patients, 156 females and 54 males, aged 13 to 66 years, were placed on the programme. Eighty-six per cent of these improved their symptom scores. Sixty-two per cent, or 48 of 78 patients, had abnormal balance studies. Fifty-seven per cent, or 12 of 21, remeasured after treatment had improved. Fifty per cent or 106 of 210 patients, had autonomic nervous system disorders as measured by the Iriscorder, and 31% had improved after treatment. Sixty-three per cent decreased their levels of toxic chemicals. These results clearly show that heat depuration physical therapy appears to be efficacious in many patients with chemical sensitivity.

New approaches in medical imaging using plastic scintillating detectors

Abstract A small animal imaging camera was built in our laboratory, using-fast plastic scintillating detectors ( τ = 2–4 ns) and position sensitive photomultipliers (Hamamatsu) digitized using flash ADCs. Pinhole collimators were used for 125 I imaging to achieve submillimeter resolution with scintillating plates of 28 mm radius and 1.5 mm thickness. A high resolution PET module was constructed with arrays of 1.0 mm diameter plastic scintillating fibers. The feasibility of high resolution imaging was demonstrated by the study of brain blood flow in a rat using 125 I IMP in single photon detection mode and with 64 Cu PTSM by using PET mode. Construction of single photon and positron emission tomographic imaging systems for small animals and subsequently for human imaging is in progress.

Imaging of folate receptors with I-125 labeled folate using small animal imaging system built with plastic scintillating optical fibers

A small animal whole body imaging device was built with plastic scintillating fibers and application of this system to image folate receptors in mice is described. The prototype imaging device consisted of two layers of 1 mm BCF-10 fibers laid on 6.98 cm acrylic core, one layer with a right handed pitch and the other with a left handed pitch. The fiber readout was performed with a position sensitive photomultiplier and a specialized flash ADC. A coaxial brass mesh collimator (1 mm thick) was used to increase spatial resolution. Histamine- folate conjugate was labeled with I-125 and was found to have receptor binding properties similar to 3H labeled compound. Imaging studies were performed in mice bearing folate receptor +ve (IGROV) tumor and receptor -ve (Meth-A) tumor. In situ imaging of animals sacrificed at 30 min post injection of the tracer showed the localization of the tumor in animals with the folate receptor +ve tumors and the results were negative in animals with receptor -ve tumor. The biodistribution studies confirmed these observations. Our initial studies demonstrate the prospects for development of agents for imaging folate receptors that may have application in drug development and the application of the small animal imaging device built with plastic scintillating detectors in imaging with low energy photons (25 - 35 keV).

Constructing a small laboratory animal imaging device based on scintillating fibers

Scintillating optical fibers have been used to build small detectors for whole-body imaging of small rodents by nuclear medicine techniques. Cylindrical detectors with entrance apertures of 6.8 cm and active lengths of 11.3 cm were constructed using both 3 mm and 1 mm BCF-10 fibers. Fiber readout was performed using position sensitive photomultipliers and a specialized flash ADC system. The efficiencies of these detectors were determined as a function of energy, their resolution was studied, and their potential use for SPECT (single photon emission computed tomography) was explored.

Development of a high resolution scintillating fiber gamma ray telescope

The authors report on further development and testing of a Compton telescope composed of scintillating fibers and position-sensitive photomultipliers. Initial tests of the telescope showed a better than 1-mm (RMS) position resolution and a 17.5-mrad (RMS) angular resolution for 1.2-MeV photons from a collimated /sup 60/Co gamma source. This type of device can be used for constructing large-area telescopes for gamma-ray astronomy. It was shown that this gamma ray telescope worked successfully. >

Testing of the spatial resolution and efficiency of scintillating fiber PET modules

Two experimental PET (positron emission tomography) camera modules were constructed using (1) two 5-cm*5-cm*2.5-cm detector stacks made of parallel 0.5- and 1.0-mm-diameter scintillating fibers and (2) two 5-cm*5-cm*5-cm detector stacks made of alternating x and y layers of 0.5- and 1.0-mm-diameter scintillating fibers. Each stack was viewed by Hamamatsu R2486 position-sensitive photomultipliers. The time resolution of the coincidence system was 10 ns. The spatial resolution and efficiency of the PET modules were tested using an approximately 1 mu Ci. 0. 5-mm-diameter Na-22 source. The best results were achieved with the 1.0-mm parallel fiber stacks: 2.0-mm spatial resolution (full width at half maximum) and 2.3% efficiency. The possibilities of improving the characteristics of this arrangement and particularly the alternating x and y layer stacks are discussed.<<ETX>>

High resolution gamma ray telescope using scintillating fibers and position sensitive photomultipliers

Abstract Recently high photon yielding and long attenuation length step index scintillating plastic fibers have been developed. Scintillating fibers of 1 mm diameter made of polystyrene doped with butyl-PBD and POPOP ( λ = 420 nm), and clad with PMMA (poly-methylmetacrylate) have resulted attenuation lengths over 2 meters. Scintillating fibers stacked up into scintillating fiber planes U, V and W that are rotated by 60° angle relative to each other and coupled to position sensitive photomultipliers can be used as high resolution imaging gamma-ray detectors. We are presenting the design of a large area gamma-ray telescope with high angular and energy resolution for space based experiments, using scintillating fibers and recently developed position sensitive photomultiplier tubes.

Folate receptor imaging with 125I labeled folic acid with a whole body small animal imaging device built with plastic scintillating optical fibers

Abstract A small animal whole body imaging cylindrical device was built with plastic scintillating fibers and position sensitive photomultipliers (Hamamatsu) and digitized using flash ADCs. A co-axial brass mesh collimator (septum thickness 1 mm) was used in combination with an electronic collimation scheme to enhance spatial resolution. Imaging studies with 125 I labeled folic acid were performed in mice bearing folate receptor +ve (IGROV) tumor and receptor −ve (Meth-A) tumor. In-situ imaging of animals sacrificed at 15–30 min post injection of the tracer showed the localization of the tumor in animals with the folate receptor +ve tumors. Our initial studies demonstrate the utility of a device built with plastic scintillating fibers in small animal imaging studies with low energy photons (25–35 keV).

A new method for detection of distant supernova neutrino bursts

Abstract We suggest a new method for detection of neutrino bursts generated by distant supernovas in our galaxy and in the local group of galaxies. This new method is based on the detection of neutrons produced in the inelastic scattering of νμ and ντ neutrinos with nuclei via the neutral current channel. The advantages of such a detector are (1) the enhancement of neutrino scattering cross sections due to nuclear collective effects, (2) the selective detection of νμ and ντ supernova neutrinos, and (3) the existence of large geological deposits of suitable neutrino detector materials in nature.