Dispersal capacity of Haematopota spp. and Stomoxys calcitrans using a mark-release-recapture approach in Belgium.

The dispersion potential of mechanical vectors is an important factor in the dissemination of pathogens. A mark-release-recapture experiment was implemented using two groups (unfed and partially fed) of the Tabanidae (Diptera) (Haematopota spp.) and biting Muscidae (Diptera) (Stomoxys calcitrans) most frequently collected in Belgium in order to evaluate their dispersion potential. In total, 2104 specimens of Haematopota spp. were collected directly from horses and 5396 S. calcitrans were collected in a cattle farm using hand-nets. Some of these insects were partially fed in vitro and all were subsequently coloured. Overall, 67 specimens of S. calcitrans (1.2%) and 17 of Haematopota spp. (0.8%) were recaptured directly on horses. Stomoxys calcitrans flew maximum distances of 150 m and 300 m when partially fed and unfed, respectively. Haematopota spp. travelled maximum distances of 100 m and 200 m when partially fed and unfed, respectively. Segregation measures seem essential in order to reduce the risk for pathogen transmission. A distance of 150 m appears to be the minimum required for segregation to avoid the risk for mechanical transmission, but in areas of higher vector density, this should probably be increased.

Secreted subtilisin Sub3 from Microsporum canis is required for adherence to but not for invasion of the epidermis.

BACKGROUND: Microsporum canis is a pathogenic dermatophyte that causes a superficial cutaneous mycosis, mainly in cats and humans. Proteolytic enzymes, including subtilisins, have been postulated to be key factors involved in adherence and invasion of the stratum corneum and keratinized epidermal structures. OBJECTIVES: To evaluate the importance of Sub3 as a M. canis virulence factor using a SUB3 RNA-silenced strain. MATERIALS AND METHODS: The stability of a previously constructed RNA-silenced strain IHEM 22957 was tested in three different ways. The involvement of Sub3 in the adherence process was evaluated using a new ex vivo adherence model of M. canis arthroconidia to feline epidermis. In order to investigate the contribution of Sub3 in epidermal invasion, the pathogenicity of the SUB3 silenced strain was compared with that of the control strain in a guinea pig model of experimental M. canis dermatophytosis. RESULTS: The silenced strain was shown to be stable after four in vitro transfers and after the in vivo experimental infection. This strain has dramatic loss of adherence capacity to feline corneocytes when compared with the parental strain. In contrast, no significant differences were observed at any time during the infection between the control strain and the SUB3 silenced strain, indicating that Sub3 secretion is not required for invasion of epidermal structures. CONCLUSIONS: RNA interference is a useful tool to evaluate pathogenic mechanisms of M. canis. For the first time, a role in pathogenicity could be attributed to a protease of a dermatophyte, namely Sub3 from M. canis, which is required for adherence to but not for invasion of the epidermis.

Coprological survey of endoparasite infections in owned dogs and owners' perceptions of endoparasite control in Belgium and the Netherlands.

Infections with endoparasites are common in dogs. Some of these parasites are potentially zoonotic and therefore a public health concern. A survey was conducted in twenty-six small animal practices to evaluate the prevalence of endoparasites in Belgian and Dutch owned dogs older than 6 months as well as risk factors associated with infection. Out of 239 faecal samples screened (168 in Belgium and 71 in the Netherlands), 18 dogs were tested positive for at least one type of endoparasite with three dogs co-infected with two parasitic species. Toxocara sp. was the most frequently found endoparasite (4.6%). Three other dogs were positive for Angiostrongylus vasorum (1.4%) using the Baermann method and confirmed in one dog by the Angiodetect® test. Age and predation behaviour were identified as two risk factors associated with endoparasite infection. Although the majority (77%) of the owners in this study reported to administer at least one anthelmintic treatment per year, only a minority of them (24.3%) were aware of the risk to human health, indicating that owner awareness is sub-optimal. For dog owners, human toxocarosis and other potential zoonoses remain an underestimated health concern. The implementation of sustainable parasite control strategies should be promoted taking also into account the public health risk.

Breakdown of the Z=8 shell closure in unbound 12O and its mirror symmetry.

An excited state in the proton-rich unbound nucleus 12O was identified at 1.8(4) MeV via missing-mass spectroscopy with the 14O(p,t) reaction at 51 AMeV. The spin-parity of the state was determined to be 0+ or 2+ by comparing the measured differential cross sections with distorted-wave calculations. The lowered location of the excited state in 12O indicates the breakdown of the major shell closure at Z=8 near the proton drip line. This demonstrates the persistence of mirror symmetry in the disappearance of the magic number 8 between 12O and its mirror partner 12Be.

Design of a Pilot SOFC System for the Combined Production of Hydrogen and Electricity under Refueling Station Requirements.

The objective of the current work is to support the design of a pilot hydrogen and electricity producing plant that uses natural gas (or biomethane) as raw material, as a transition option towards a 100% renewable transportation system. The plant, with a solid oxide fuel cell (SOFC) as principal technology, is intended to be the main unit of an electric vehicle station. The refueling station has to work at different operation periods characterized by the hydrogen demand and the electricity needed for supply and self-consumption. The same set of heat exchangers has to satisfy the heating and cooling needs of the different operation periods. In order to optimize the operating variables of the pilot plant and to provide the best heat exchanger network, the applied methodology follows a systematic procedure for multi-objective, i.e. maximum plant efficiency and minimum number of heat exchanger matches, and multi-period optimization. The solving strategy combines process flow modeling in steady state, superstructure-based mathematical programming and the use of an evolutionary-based algorithm for optimization. The results show that the plant can reach a daily weighted efficiency exceeding 60%, up to 80% when considering heat utilization.

In vitro entomopathogenic activity of Beauveria bassiana against Psoroptes spp. (Acari: Psoroptidae).

An indigenous strain (IHEM 18747) of Beauveria bassiana (Balsamo) Vuillemin (Deuteromycetes) was evaluated for its in vitro entomopathogenic activity against the parasitic mite Psoroptes ovis Hering (Acari: Psoroptidae) from rabbits. The following aspects were evaluated: (1) effects of conidial concentration on the viability of adult females; (2) influence of the infection on the fertility, and on the hatchability of eggs; (3) and transmission of infection between mites, and from contaminated surface. Adult females immersed into increasing concentrations of conidia (10(4)-10(9)conidia ml(-1)) showed a dose-related susceptibility. At the highest concentration of conidia, LT50 was 1.6 days while LT50 of the controls reached 5.8 days. The fungus was able to sporulate on the body surface and 100% of the mites were covered with mycelium after immersion in solutions containing 10(7)-10(9)conidia ml(-1). One hundred percent of healthy mites exposed to infected cadavers or surfaces acquired the infection (LT50 reached 1.9 and 1.73 days, respectively, versus 6.1 and 5.1 days in controls, respectively). Egg laying was not reduced by the fungal infection but both the hatchability of the eggs and the life span of the emerging larvae were significantly reduced. Eggs directly infected with the fungus did not show reduced hatchability but the life span of the larvae was shortened. It is concluded that B. bassiana has a high entomopathogenic activity against Psoroptes spp. The in vivo use of this biocontrol agent against Psoroptes spp. in rabbit, sheep and cattle deserves further attention.

Neoadjuvant chemotherapy and irradiation in multiple synchronous squamous cell carcinoma of the upper aero digestive tract.

Twenty-four patients with multiple, synchronous carcinoma of the head and neck, lung or esophagus, were treated with induction chemotherapy followed by irradiation to involved areas. Chemotherapy regimen consisted of cisplatinum either alone, or in combination with 5-FU or etoposide. Subsequently, external radiotherapy, 60-65 Gy and 70-75 Gy to the mediastinum and the head and neck areas, respectively, was carried out. Following chemotherapy, three patients (12.5%) had a complete clinical remission in both cervical and mediastinal sites. That rate was significantly increased by radiotherapy (66%). Tolerance was fair or mild even though half of the patients needed a rest break during irradiation. Follow-up ranges from 24 to 38 months. The median survival is 12 months and the actuarial survival rates are 45% and 5% at 12 and 24 months, respectively. It is suggested that induction chemotherapy will not drastically improve the overall prognosis of multiple squamous cell carcinoma of the upper aero digestive tract and that external irradiation remains a major part of treatment which should not be reduced in treated volumes, or in total dose delivered.

Serum levels of CA-50, CA-19.9, CA-125, CA-15.3, enolase and carcino-embryonic antigen in non neoplastic diseases of the lung.

There is not as yet a specific marker for lung cancer. We tested the specificity of six serum markers using radio-immunological assays (CA-50, CA-19.9, CA-125, CA-15.3, Enolase, CEA) in 60 patients with non-neoplastic diseases of the lung (COPD: 28 patients, acute pneumonia: 23 patients, allery: 9 patients). No correlation was found between the percentage of false positivities on the one hand, and sex, age and smoking habits on the other. CA-125 proved to be positive in 74% of acute pneumonia cases. The rate of false positive values is low with CEA (3.3%), Enolase (6.7%) and CA-15.3 (5%) and therefore the cut-off value we chose for these markers was adequate. This is not the case with CA-50, CA-19.9 and CA-125, for which we observed a high rate of false positive values (33.3%, 13.3% and 53.3% respectively) and for which higher cut-off values must be adopted.

CA-50 and CA-19.9 as tumour markers: which is preferable?

CA-50 (Kit IRMA Stena Diagnostic, cut-off value: 16 U/ml) and CA-19.9 (Kit SPAC Mallinckrodt were compared in a prospective study including 323 cancer patients (56% metastatic) and 120 patients with non neoplastic disease. The CA-50 and CA-19.9 sensitivities were 41.8% and 39% respectively; the CA-50 sensitivity was greater in the cancers of the gastro-intestinal (GI) tract (61.3% versus 51.6% alpha less than 0.00001) and did not differ in the other cases. The CA-19.9 specificity was greater (77.5% versus 64.2% alpha less than 0.0001), due to a greater specificity in the case of respiratory diseases (86.7% versus 66.7% alpha less than 0.0001). A good correlation was found between the serum levels of the two markers in each group of patients (cancer r = 0.78, alpha less than 0.001; benign diseases r = 0.69, alpha less than 0.001). This study has shown a close correlation between these two markers; the reliabilities of CA-50 and CA-19.9 were similar, particularly in the gastro-intestinal diseases (58.3% versus 51.3%). In conclusion, CA-50 and CA-19.9 are both good markers of cancers of the GI tract. Their simultaneous assay would be useless.

Analysis of CA-125 levels in the sera of patients with non-ovarian carcinomas and non-malignant diseases.

CA-125 is known as a marker of ovarian carcinoma; it is useful in monitoring response to treatment and it is even said to be a means of detecting ovarian carcinomas. We have studied the serum levels of CA-125 in 260 patients with advanced carcinomas (excluding ovarian cancer) and in 120 patients with non-malignant diseases (excluding gynaecological diseases). Our cut-off value was 20 IU/ml. Sensitivity was 0.53 and Specificity only 0.38; sensitivity was high in lung cancer (0.56), in breast cancer (0.46) and in cancer of the stomach (0.91). Five percent of the cancer patients had values higher than 233.5 IU/ml. Sensitivity was correlated with the presence of a metastatic disease (p less than 0.001). A second assay was obtained in 163 cases; a concordance between the variation of the serum level and the clinical evolution was found in 65% cases. A high rate of false positive values was found in cases of acute pneumonia (0.74) and of gastro-intestinal diseases (0.41). In view of these results, the optimal threshold value was set at 65 IU/ml. CA-125 appears to be a useful marker in the monitoring of advanced non-ovarian carcinomas.

A phase III of cisplatinum versus cisplatinum-etoposide for previously untreated squamous cell carcinoma of the head and neck.

136 patients with previously untreated stage III or IV squamous cell carcinoma of the head and neck entered a prospective randomized trial to compare the efficacy and toxicity of DDP vs DDP-VP 16 213 (Etoposide). 69 patients (group A) were given three courses of DDP 100 mg/m2 administered on day 1, while 67 patients (group B) were given three courses of a combination of Etoposide 100 mg/m2 per os administered on days 1 to 5 and DDP 100 mg/m2 on day 4. Objective response rate appeared to be low in both groups: in group A (60 evaluated patients) CR = 1, PR = 9; CR + PR = 14.5%, and in group B (57 evaluated patients) CR = 3, PR = 8; CR + PR = 16.4% (p greater than 0.4). One drug-related death occurred in each group. There was no difference in toxicity between the two treatments with regard to leukopenia, thrombopenia, vomiting and nephrotoxicity. Thus this schedule of oral Etoposide does not seem to increase either the efficacy or the toxicity of DDP.

Correlation of clinical pharmacokinetic parameters of cisplatin with efficacy and toxicity.

Twenty-two pharmacokinetic studies were carried out in 11 patients receiving cisplatin (20 mg/m2 per d) associated with etoposide (50 mg/m2 per d), as 5-day continuous infusions, every 4 weeks. Blood was withdrawn at 8:30 am from day 1-5. Within 15 min after taking the blood, an aliquot of plasma was filtered for the ultrafilterable platinum (UP) assay. Total platinum (TP) and UP were assayed by flameless atomic absorption. The plasma concentrations and AUC0-120 h of TP were correlated with those of UP (P less than 0.05 to P less than 0.001). TP concentrations increased significantly during the infusion and with each successive course, whereas the increase of plasma concentration of UP during and between courses was not statistically significant. The responders had significantly higher levels of TP (AUC, concentrations) in the first and second courses than the non-responders. No renal toxicity was observed, nevertheless, the AUC0-120 h of TP and UP were positively correlated with the serum creatinine (P less than 0.05). The digestive intolerance (grade 1-3) was significantly correlated with TP concentrations and AUC0-120 h. There was no statistical difference in UP concentrations either between responders and non-responders in any course, nor between toxic and non-toxic courses. Since etoposide was concomitantly administered, we can formulate the conclusion as follows: no "objective" response was observed in the patients with low TP plasma concentrations and AUC0-120 h.

Serum levels of CA-50, CA-19.9, CA-125, neuron specific enolase and carcinoembryonic antigen in lung cancer and benign diseases of the lung.

The serum levels of five markers (CA-50, CA-19.9, CA-125, Enolase (NSE) carcinoembryonic antigen (CEA) were studied in 96 lung cancer patients and in 60 patients with benign diseases of the lung: sensitivity was 0.44, 0.41, 0.54, 0.23 and 0.38 respectively; specificity was 0.67, 0.87, 0.47, 0.93 and 0.97 respectively. Serum levels of CA-125 over 20 U/ml were found in 74% of patients with acute pneumonia. A good parallel existed between the clinical evolution of lung cancer and the variations in the serum level of CA-50, CA-19.9 and NSE. Although the pretreatment result was elevated, successive assays of the marker allowed the clinical evolution to be followed. Conflicting results were found with CA-125 and to a lesser extent with CEA. A close correlation existed between the serum levels CA-50 and CA-19.9 in the 2 groups of patients. In the absence of a specific marker for lung cancer, complementary information can be provided by means of a simultaneous determination of CEA, NSE, CA-19.9--or CA-50--and CA-125.

Microbial contamination of enteral feeding tubes occurring during nutritional treatment.

Enteral nutrition is an effective treatment for catabolic patients with normal intestinal absorption. However, tube-fed patients are at risk from superinfection. Our study is the first to evaluate in vivo the microbial contamination of solutions staying in the nasogastric tube of cancer patients receiving nutritional preparations. After daily feeding, the tube was rinsed with nonsterile tap water. Tap water staying overnight in the tube was considered as tube-rinsing solution. Microbial burden of nutritional preparations was determined on the fifth day of enteral nutrition, from opening the first container and throughout feeding. The next day, a sample of the tube-rinsing solution was cultured. All bacterial species were identified and antibiotic susceptibility pattern was assessed. Thirty-one cancer patients were included, 12 on the hospital's preparations and 19 on commercial feeding. Seven of the hospital--and none of the commercial--preparations were contaminated. Among the 48 samples collected during feeding, 16 were contaminated, including 10 hospital and 6 commercial preparations. All the 31 tube-rinsing solutions were contaminated and 102 strains cultured. Their median concentration was 10(6) colony-forming units/mL (range 10-10(10)). The strains were 48 Enterobacteriaceae, 20 group D streptococci, 9 Candida albicans, 9 Pseudomonas aeruginosa, and 16 others. Multiple antibiotic resistance was present in 12 of the 102 strains. Lower resistance was present in 33. The predominant microorganism of the tube-rinsing solution caused a bacterial colonization for three febrile patients. In conclusion, the feeding tube is an important reservoir for multiple antibiotic-resistant bacteria.

[CA-125 in non-ovarian benign and malignant pathology: study on 380 patients]. / Le CA-125 en pathologie bénigne et maligne non ovarienne: étude portant sur 380 patients.

CA-125, a serum marker of epithelial ovarian cancer, was studied by a radioimmunometric method: the sensitivity and specificity of the assay was studied in 260 patients with non ovarian carcinomas and 120 patients with non malignant diseases. The ideal threshold value has been discussed. Levels higher than 20 UI/ml (cut-off value) have been found in 53% of cases. Sensitivity falls to 25% if the cut-off value is 65 UI/ml. The serum levels correlated well with the existence of a metastatic disease (P less than 0.001). A second assay allowed to study in 163 cases the correlation between the variations of the serum level and the clinical evolution; a good correlation was found except in case of stable disease. High levels have also been found in patients with benign diseases, most of all in cases of pneumonia and severe liver cirrhosis.

[Correlations between clinical pharmacodynamics and pharmacokinetics of cisplatin and etoposide]. / Corrélations entre la pharmacodynamie clinique et la pharmacocinétique clinique du cisplatine et de l'étoposide.

Currently, the dose of anticancer drugs is adjusted according to patient body surface area, although the best criterion for dose adjustment seems to be the plasma concentration of the drug, since a correlation has been established between plasma concentration and efficacy for several drugs. We report here similar results with etoposide and cisplatinum. The plasma concentration and the area under the curve (AUC) of etoposide and platinum (Pt) were higher in responders compared to non-responders, and etoposide clearance was higher in responders. The etoposide toxicity (assessed by the polymorphonuclear blood count) was higher in responders. There was a good correlation between the Pt concentration and creatininaemia. The AUC for Pt was significantly higher in patients with nausea and vomiting. There was no correlation between the infected dose of either drug and efficacy or toxicity. It is not possible to assign efficacy to either compound since they were injected simultaneously. We conclude that when the plasma etoposide or platinum concentrations are low, tumour response is unlikely.

[MRI in the early diagnosis of spinal metastases of bronchial cancer]. / IRM dans le diagnostic précoce des métastases vertébrales du cancer bronchique.

MRI of the whole spine and radionuclide bone scan were performed prospectively on 50 consecutive patients with newly diagnosed non small-cell lung carcinoma. The final diagnosis of vertebral metastasis was made by means of follow-up studies. The prevalence of vertebral metastasis was 24% (12/50 patients). The sensitivity of MR imaging (92%) was superior to that of radionuclide bone scan (67%) in the detection of vertebral involvement, the specificity was the same (94%). MRI of the spine was not useful as a screening procedure before treatment, but offered advantages over radionuclide bone scan in patients with symptoms and when bone scintigraphy detected abnormal foci, including identification of additional vertebral metastatic foci and better analysis of the extent of metastatic involvement within vertebrae.

[Blood levels of CA-50, CA-19.9, CA-125, enolase, CA-15.3 and carcinoembryonic antigen in non-cancerous bronchopulmonary pathology]. / Taux sériques du CA-50, CA-19,9, CA-125, énolase, CA-15,3 et antigène carcino-embryonnaire en pathologie broncho-pulmonaire non tumorale.

At present we do not possess a specific marker of broncho-pulmonary cancers. We propose to test the specificity of six serum markers labelled by radio-immunological methods (CA-50, CA-19.9, CA-125, CA-15.3, enolase, ACE) in 60 patients suffering from non-tumoural broncho-pulmonary disorders: chronic airflow obstruction = 28, acute infective bronchopulmonary disorders = 23, allergy = 9. We have not found any correlation between the percentage of false positives and sex, age or smoking. On the other hand, the CA-125 was often found to be positive in cases of acute pneumonia. Overall the frequency of false positives with ACE (3.3%) enolase (6.7%) and CA-15.3 (5%) is weak. The threshold of positivity obtained is adequate. This is not the case with CA-50 (33.3%), CA-19.9 (13.3%) and above all CA-125 (53.3%), for these we suggest new thresholds of positivity.

[Laser treatment in malignant tracheo-bronchial pathology]. / Le traitement par laser en pathologie maligne trachéo-bronchique.

The laser is of proved efficacy in tracheo-bronchial pathology, provided the indication is well selected. Their current role is minimal. Perspectives are opening up in terms of the photoradiation of dysplasia, carcinomas in situ and small tumors.

[Comparative analysis of serum levels of CA-50, CA-125, CA-19.9, enolase and CEA in bronchopulmonary cancer]. / Analyse comparative des taux sériques de CA-50, CA-125, CA-19.9, enolase et ACE dans les cancers broncho-pulmonaires.

A serum assay of CA-50, CA-125, CA-19.9, ENOLASE (NSE) and CEA was performed in 65 patients with primary lung cancer, 63% of whom had visceral metastases, with the following histological distribution: squamous carcinoma (40), adenocarcinoma (9), large cell carcinoma (4), oat cell carcinoma (12). A raised CEA level was detected in 37% of cases, compared with 40.6% for CA-50, 44.6% for CA-19.9 and 40.6% for CA-125 and only 26.6% for NSE. Overall, at least one marker was positive in 83% of cases. Statistical analysis of the different markers (correlation analysis and principal component analysis) demonstrated the existence of a strict correlation between the levels of CA-50, CEA and CA-19.9 (p less than 0.01). ENOLASE was more frequently elevated in oat cell carcinomas (42%) than in non-oat cell carcinomas (30%), but the difference was not significant. In contrast, CA-125 appears to be a good marker for non-oat cell carcinomas (51%) (p less than 0.05). The authors also found a correlation between the presence of a raised level of CA-50 (p less than 0.05), CA-125 (p less than 0.02) and especially CEA (p less than 0.001) and the presence of visceral metastases. The initial survey of disseminated lung cancers should include the assay of at least 4 of these markers in order to obtain a reliable serum tracer in more than 2/3 of cases.