Diagnosis of transfusion-associated graft-versus-host disease by polymerase chain reaction in fludarabine-treated B-chronic lymphocytic leukaemia

Transfusion-associated graft-versus-host disease (TA-GVHD), has rarely been reported associated with B-chronic lymphocytic leukaemia (B-CLL). We report a patient diagnosed with B-CLL, previously treated with fludarabine, who developed TA-GVHD after being transfused during surgery for splenectomy. Diagnosis was confirmed by polymerase chain reaction (PCR) detection of donor DNA in the patient, by amplification of Y-chromosome sequence and analysis of minisatellite polymorphisms. B-CLL patients treated with fludarabine appear to be at risk for TA-GVHD and should be regarded as candidates for transfusions with irradiated blood products. This case illustrates that PCR is a rapid technique for the early diagnosis of TA-GVHD.     

Fatal Campylobacter jejuni infection in a patient splenectomised for thalassaemia

A 35 year old man with a fatal Campylobacter jejuni infection is described. He had HbE/beta zero thalassaemia and had undergone splenectomy nine months previously for hypersplenism; he also had chronic hepatitis C infection. He presented with high grade fever but no gastrointestinal symptoms and rapidly progressed to septicaemic shock and hepatic encephalopathy despite treatment with penicillin, gentamicin, and, later, chloramphenicol and ceftazidime. Only one case of Campylobacter jejuni septicaemia occurring post-splenectomy has been reported previously, also in an iron overloaded thalassaemia patient. Unusual Gram negative bacilli must be covered by the chosen antibiotic regimen when splenectomised thalassaemic patients present with high grade fever.     

On the influence of environment gases, relative humidity and gas purification on dielectric charging/discharging processes in electrostatically driven MEMS/NEMS devices

In this paper, we investigate the impact of environment gases and relative humidity on dielectric charging phenomenon in electrostatically actuated micro- and nano-electromechanical systems (MEMS and NEMS). The research is based on surface potential measurements using Kelvin probe force microscopy (KPFM). Plasma-enhanced chemical vapor deposition (PECVD) silicon nitride films were investigated in view of applications in electrostatic capacitive RF MEMS switches. Charges were injected through the atomic force microscope (AFM) tip, and the induced surface potential was measured using KPFM. Experiments have been performed in air and in nitrogen environments, both under different relative humidity levels ranging from 0.02% to 40%. The impact of oxygen gas and hydrocarbon contaminants has been studied for the first time by using different gas purifiers in both air and nitrogen lines. Voltage pulses with different bias amplitudes have been applied during the charge injection step under all investigated environmental conditions in order to investigate the effect of bias amplitude. The investigation reveals a deeper understanding of charging and discharging processes and could further lead to improved operating environment conditions in order to minimize the dielectric charging. Finally, the nanoscale KPFM results obtained in this study show a good correlation with the device level measurements for capacitive MEMS switches reported in the literature.     

Discoloration of a red cationic dye by supported TiO(2) photocatalysis

The degradation under UV, visible and sunlight irradiation of C.I. Basic Red 46 (BR 46) dye used for acrylic fibers dyeing has been studied in a lab-scale continuous system with two different immobilized TiO(2) systems. Catalyst I was based on TiO(2) particles deposited on cellulose fibers; Catalyst II combined TiO(2) particles deposited on a layer of cellulose fibers (as in Catalyst I) with a layer of carbon fibers and finally a layer of cellulose fibers. The treatment of aqueous dye solutions and industrial wastewater contaminated with the same dye has been evaluated in terms of color removal and chemical oxygen demand (COD) decrease. With UV light, aqueous solutions containing dye were decolorized slightly more rapidly with Catalyst II than with Catalyst I. Sunlight was also very effective and experiments involving sunlight irradiation showed Catalyst II to be the more efficient, giving more than 90% discoloration after 20 min of treatment. Comparing the discoloration yield by adsorption or under visible light for both catalysts, it was observed that the difference between them is below 5%. The adsorption kinetics was found to follow a second-order rate law for Catalyst I and a first-order rate law for Catalyst II. The kinetics of photocatalytic degradation under UV or sunlight were found to follow a first-order rate law for both catalytic systems. Under sunlight the COD removal yield for textile wastewater reaches 33% with Catalyst I against 93% with Catalyst II.     

The nervous system function of patients with periodontitis

Analysis of the function of the nervous system, based on clinical, neurological, and psychological studies in 78 patients with generalized periodontitis, revealed central regulation disorders without signs of organic lesions of the brain in 76% patients. The authors claim that stress and a high level of personal anxiety may be responsible for the development of these disorders, which was confirmed by the results of psychological testing.     

A region within murine chromosome 7F4, syntenic to the human 11q13 amplicon, is frequently amplified in 4NQO-induced oral cavity tumors

Our previous reports have shown that two thirds of 4-nitroquinoline-1-oxide (4NQO)-induced murine oral squamous cell carcinomas (SCC) have Hras1 mutations. Loss of heterozygosity (LOH) involving the distal portion of chromosome (Chr) 7 occurred in half of the tumors with Hras1 mutations. Here, we demonstrate that five of six tumors with LOH have 4-8-fold amplification involving the distal portion of Chr 7 (7F4). Ccnd1. Fgf4 and Fgf3, within the most telomeric region of Chr 7 (70.5 cM), are co-amplified. The region is syntenic to a previously identified human amplicon at 11q13. Only one out of eight tumors without LOH at Chr 7 had twofold amplification; the other seven had no detectable amplification. Significant amplification is restricted to the chromosome with the Hras1 mutation. Gene amplification occurred without overexpression since only one of five tumors with amplification and one of six tumors without Ccnd1 amplification expressed increased protein. Although amplification of 11q13 occurs rather frequently in human tumors, 4NQO-induced oral cavity tumors in inbred mice are the first example of a murine tumor with consistent amplification. Our observations are strikingly similar to human head and neck SCC where overexpression of genes within the 11q13 amplicon is inconsistently detected. The amplification of genes localized to human 11q13 and the syntenic region on murine Chr 7 during tumorigenesis suggests that similar structural elements are present which predispose these regions to amplification during malignant transformation.