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Short-term on-site composting of poultry carcasses and broiler litter (BL) is considered as a feasible technology for pathogen elimination during events of mass mortality in poultry houses. However, factors related to mass losses and physical transformation of the poultry carcass, and associated emissions of volatile organic compounds (VOCs) and odors, have not been thoroughly evaluated. This study aims to characterize the degradation of separated carcass parts co-composted with BL and the associated air emissions during 30 days of enclosed composting at 50 °C with constant aeration. The study was carried out in lab-scale simulators using five mixtures containing feathers, rib bones, skins, breast muscles, and hearts and livers, prepared at a 1:2 volumetric ratio (carcass:BL). Dry mass losses reached 59.5, 41.1, 60.8 and 103.5% (based on weight) or 48.4, 29.6, 49.7, and 94.8% (based on CO2-C and NH3-N emissions), for rib bones, skins, breast muscles, and hearts and livers, respectively. Visually, most of the carcass parts were degraded, and the typical carcass odor had disappeared by the end of the 30 days. Out of 24 VOCs, dimethyl disulfide (DMDS) and dimethyl trisulfide (DMTS) contributed 80.7-88.3% of the total VOC flux, considering the partial contribution of each part to the emissions involved with the whole carcass. DMDS, DMTS, benzaldehyde, methanethiol, pentanoic acid, and NH3, contributed 90.5-97.9% of the odor activity values during composting. DMDS/DMTS ratio is suggested as a potential biomarker of stabilization and readiness of the compost for transportation toward further treatment or safe burial.

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Understanding and optimization of composting processes can benefit from the use of controlled simulators of various scales. The Agricultural Research Organization Composting Simulator (ARO-CS) was recently built and it is flexibly automated by means of a programmable logic controller (PLC). Temperature, carbon dioxide, oxygen and airflow are monitored and controlled in seven 9-l reactors that are mounted into separate 80-l water baths. The PLC program includes three basic heating modes (pre-determined temperature profile, temperature-feedback ("self-heating"), and carbon dioxide-dependent temperature), three basic aeration modes (airflow dependence on temperature, carbon dioxide, or oxygen) and enables all possible combinations among them. This unique high flexibility provides a robust and valuable research tool to explore a wide range of research questions related to the science and engineering of composting. In this article the logic and flexibility of the control system is presented and demonstrated and its potential applications are discussed.

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Composting in closed polyethylene sleeves with forced aeration may minimize odor emissions, vectors attraction and leachates associated with open windrows. The present study demonstrates the use of this system for composting olive mill wastewater (OMW), the undesired stream associated with the olive milling industry. A polyethylene sleeve of 1.5-m diameter and ca. 20-m long was packed with shredded municipal green waste which was pre-soaked in OMW for 72 h. Process conditions were controlled by means of a programmable logic controller (PLC) equipped with temperature and oxygen sensors. Thermophilic temperatures (>45 °C) were maintained for one month followed by temperatures in the range of 30-40 °C, ca. 20 °C above ambient temperature, for a period of 3.5 months. Oxygen levels were controlled and the system was kept aerobic. Water content gradually decreased with sufficient levels for efficient composting. The finished compost was non-phytotoxic to Cress (Lepidium sativum L.) in a lab bioassay. It was also found suitable as an ingredient in peat, tuff, and coir based growing media, evaluated by plant growth tests with basil and ornamental plants. The viability of this approach for disposing off OMW is much dependent on the liquid absorption capacity of the vegetative waste.

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Composting in polyethylene sleeves with forced aeration may minimize odor emissions, vectors attraction and leachates associated with open windrows. A disadvantage of this technology is the lack of mixing during composting, potentially leading to non-uniform products. In two pilot experiments using biosolids and green waste (1:1; v:v), thermophilic conditions (>45°C) were maintained for two months, with successful control of oxygen levels and sufficient moisture. Emitted odors declined from 1.5-3.8×105 to 5.9×103-2.3×104 odor units m-3-air in the first 3weeks of the process, emphasizing the need of odor control primarily during this period. Therefore, composting might be managed in two phases: (i) a closed sleeve for 6-8weeks during which the odor is treated; (ii) an open pile (odor control is not necessary). Reduction of salmonella, E. coli and coliforms was effective initially, meeting the standards of "Class A" biosolids; however, total and fecal coliforms density increased after opening the second sleeve and exceeded the standard of 1000 most probable number (MPN) per g dry matter. Compost maturity was achieved in the open piles following the two sleeves and the final compost was non-phytotoxic and beneficial as a soil additive.

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Olive mill wastewaters (OMW) were obtained at laboratory scale by milling olives from four cultivars grown at different irrigation levels and harvested at different times. Samples were compared based on wastewater quantity, pH, suspended matter, salinity, organic load, total phenols, NPK, and phytotoxicity. Principal component analysis discriminated between harvest times, regardless of olive cultivar, indicating substantial influence of fruit ripeness on OMW characteristics. OMW properties were affected both by the composition and the extraction efficiency of fruit water. As the fruit water content increased, the concentrations of solutes in the fruit water decreased, but the original fruit water composed a larger portion of the total wastewater volume. These contradicting effects resulted in lack of correlation between fruit water content and OMW properties. The significant effects shown for fruit ripeness, irrigation and cultivar on OMW characteristics indicate that olive horticultural conditions should be considered in future OMW management.

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AIMS: To examine flagella role and cell motility in adhesion of Achromobacter piechaudii to chalk. METHODS AND RESULTS: Transmission electron microscopy revealed that stationary cells have thicker and longer flagella than logarithmic cells. SDS-PAGE analysis showed that flagellin was more abundant in stationary cells than logarithmic ones. Sonication or inhibition of flagellin synthesis caused a 30% reduction in adhesion to chalk. Preincubation of chalk with flagella extracts reduced adhesion, by 50%. Three motility mutants were isolated. Mutants 94 and 153 were nonmotile, expressed normal levels of flagellin, have regular flagella and exhibited reduced adhesion. Mutant 208 expressed low levels of flagellin, no flagella and a spherical cell shape but with normal adhesion capacity. CONCLUSIONS: Multiple cell surface factors affect the adhesion efficiency to chalk. Flagella per se through physical interaction and through cell motility contribute to the adhesion process. The adhesion behaviour of mutant 208 suggests that cell shape can compensate for flagellar removal and motility. SIGNIFICANCE AND IMPACT OF THE STUDY: Physiological status affects bacterial cell surface properties and hence adhesion efficiency to chalk. This interaction is essential to sustain biodegradation activities and thus, remediation of contaminated chalk aquifers.

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OBJECTIVES: Phyllodes tumors of the breast (PTB) are rare fibro epithelial tumors. Their terminology, histological classification and their treatment are exposed to controversy. The aim of our work is to underline the epidemiological, clinical, histological, therapeutical, prognostic and evolutive features of these tumours through a retrospective study and a review of the literature. PATIENTS AND METHODS: We reviewed at the National Institute of Oncology of Rabat, Morocco, between 1985 and 1998, all the files of patients with histological certainty of PTB, doubtful PTB were excluded. We collected epidemiological, clinical, histological, therapeutical, prognostic and evolutive features of these tumours. STATISTICS: quantitative parameters were represented by mean +/- S.D. and qualitative parameters by percentage or effective. RESULTS: We studied nine cases of PTB, which represented 0.09% of all primitive tumors of the breast treated at our institution during the study period. All our patients were female. Mean age was 37.3 +/- 10.07 years. Two of our patients (22.2%) had a history of fibroadenoma and 44.4% were nulliparous. Mean delay before consulting was 60.7 +/- 17.56 months and the median tumour size was 13 +/- 7.47 cm. Pathological findings were six benign or borderline phyllodes tumours (66.7%) and three cystosarcomas phyllodes (33.3%). The treatment consisted in simple mastectomy in seven cases (77.8%) and tumorectomy in two cases (22.2%). All the surgical margins were clear. Two of the three cystosarcomas phyllodes received adjuvant external bean radiation therapy 50 Gy on the thoracic chest wall. After a median outcome of 3 +/- 2 years ranging from 3 to 74 months, we did not note any relapse or metastasis. DISCUSSION AND CONCLUSION: In our series, PTB happened exclusively in females. History of fibroadenoma within 22.2% of the patients suggests the hypothesis of a filiation between these two entities. Their distinctive features were young age in diagnosis, long delay before consulting, important tumor size, predominant benign and borderline histological types, treatment mainly surgical and good local and distant control.

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AIM: To investigate the factors governing the adhesion and activity of the 2,4,6-tribromophenol (TBP) degrading bacterium Achromobacter piechaudii TBPZ-N61 on chalk from a contaminated aquifer. METHODS AND RESULTS: Adhesion kinetics of TBPZ-N61 to grey and white chalk from a polluted fractured chalk aquifer was tested in a batch system. Both grey and white chalk contain ca 80% CaCO3, while grey chalk contains more organic matter (2.4%) than the white chalk (0.3%) and also contains Dolmite and Clinoptilolite. Adhesion of the bacterial cells to the chalk particles (<0.2 mm) occurred rapidly (96% of the cells within 15 min). Langmuir-fitted adhesion isotherms suggest that cells in the stationary phase, which are more hydrophobic, adhere to both grey and white chalk more efficiently than cells in the logarithmic growth phase. Increasing the pH (from 6.7 to 8.1) caused a significant reduction in cell adhesion to the chalk. Activity of attached cells was evaluated in both batch and column experiments. Logarithmic cells adhering to white and grey chalk were more active in TBP degradation than cells in suspension. In column experiments, significant TBP degradation was retained up to 30 days after a single injection of TBPZ cells. Thereafter, activity was fully recovered by amendment of yeast extract. Chalk surfaces that were incubated in situ in contaminated groundwater for 20 days still allowed the adhesion and activity of TBPZ cells. CONCLUSIONS: Taken together, our results show that bacteria adhere efficiently to specific sites on the chalk surfaces, and that sustained bacterial activity of the attached cells can be achieved by adding a carbon source such as yeast extract which also overcome toxic constituents that may occur in some chalk types. SIGNIFICANCE AND IMPACT OF THE STUDY: Bioremediation of TBP-contaminated chalk aquifers is made possible by the injection of bacterial cultures.

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Angiocentric lymphoma of the face is a rare malignancy. During 11 years, only two patients were treated for a lymphoma of the face. The first patient, 31-year-old, had an angiocentric lymphoma of the nasal cavity, the second patient, 40-year-old, had an angiocentric lymphoma of the nasopharynx and the maxillary sinuses, with an extension the hard palate. According to the Ann Arbor classification, the disease was stage IEab and stage IIEbb, respectively. The first patient was treated by chemotherapy alone (COP regimen) and the second patient underwent combined chemotherapy (CHOP) and radiotherapy. The follow-up was marked by progression of the disease 7 and 9 months after the end of the treatment in the two cases. For the angiocentric lymphoma, treatment based on radiotherapy or chemotherapy alone or combined does not often provide local control and the overall survival rate does not exceed 40% at 5 years.

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Nasopharyngeal adenoid cystic carcinoma is a rare tumor, few cases have been reported in the literature. The aim of this report is to present a new case of an adenoid cystic carcinoma of the nasopharynx. We report the case of a 50 years-old woman presenting with an adenoid cystic carcinoma of the nasopharynx with diffuse pulmonary metastasis. The treatment combined chemotherapy, based on cisplatin and adriamycin drugs, and palliative radiation therapy at the dose of 30 Gy. The patient died 6 months after diagnosis establishment. The best treatment of adenoid cystic carcinoma is complete surgical resection but extended resection can be difficult in some locations as nasopharynx. The adjuvant radiation therapy seems to improve local control.

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Muscular metatasis are rare, their number is probably underestimate. The authors report a case of a patient treated, in 1993, for a squamous cell carcinoma of the uterine cervix. Five years later, the patient developed a metatasis to muscular psoas. She underwent combined surgical excision and adjuvant radiation therapy. The patient is alive and well 30 months after diagnosis of the metastasis.

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Primary squamous cell carcinoma of the breast is a rare neoplasma included in metaplastic breast cancer. The histogenesis remains unknown. Clinical and radiological appearances are not specific. Nodal involvement is rare and hormones receptors are negative. The treatment is based on surgery associated to radiation therapy and chemotherapy. Prognosis seems to be similar to others breast carcinoma. We report three cases of primary squamous cell carcinoma of the breast recruited at National Institute of Oncology with review of the literature.

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Botryoïde sarcoma of the uterine cervix is a very rare tumor of the young woman or during genial activity. Less than 100 cases have been reported in the literature. The treatment ranged from radical surgery to conservative surgery followed by chemotherapy. We report a case of cervical botryoide rhabdomyosarcoma occurred in a 33 year-old woman treated primary by chemotherapy followed by surgery and adjuvant chemotherapy. The patient died by extensive metastatic retroperitoneal nodes and lung.

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Hodgkin disease intracranial lesions are uncommon. We report the case of a 24-year-old man who presented with an intracranial relapse without other evidence of disease 24 months after multiple drug therapy and extended field radiation therapy for stage III Bb type 3 Hodgkin disease. The patient was treated by whole brain irradiation (40 Gy/20 fractions/4 weeks). Six months after completion of therapy, the patient had a second relapse, with bilateral inguinal metastatic nodes, which were treated by a second line polychemotherapy. The patient was free of disease 9 months later.

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Mutations in the PITX2 bicoid-like homeobox gene cause Rieger syndrome. Rieger syndrome is an autosomal-dominant human disorder characterized by glaucoma as well as dental hypoplasia, mild craniofacial dysmorphism, and umbilical stump abnormalities. PITX2 has also been implicated in the development of multiple organs and left-right asymmetry in the body plan. The PITX2 homeodomain has a lysine at position 50, which has been shown to impart the bicoid-type (TAATCC) DNA binding specificity to other homeodomain proteins. A mutation (K88E), found in a Rieger syndrome patient, changes this lysine to glutamic acid. We were intrigued by the relatively pronounced phenotypic consequences of this K88E mutation. In the initial analyses, the mutant protein appeared to simply be inactive, with essentially no DNA binding and transactivation activities and, unlike the wild type protein, with an inability to synergize with another transcription factor, Pit-1. However, when the K88E DNA was cotransfected with wild type PITX2, analogous to the patient genotype, the K88E mutant suppressed the synergism of wild type PITX2 with Pit-1. In contrast, a different PITX2 homeodomain mutant, T68P, which is also defective in DNA binding, transactivation, and Pit-1 synergism activities, did not suppress the wild type synergism with Pit-1. These results describe the first dominant negative missense mutation in a homeodomain and support a model that may partially explain the phenotypic variation within Rieger syndrome.

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Severe deficiency of methylenetetrahydrofolate reductase (MTHFR) is the most common inborn error of folate metabolism. Patients are characterized by severe hyperhomocysteinemia, homocystinuria and a variety of neurological and vascular problems. Eighteen rare mutations have been reported in this group of patients. Two polymorphisms which cause mild enzyme deficiencies have been described (677C-->T and 1298A-->C). The first sequence change encodes a thermolabile enzyme and is associated with mild hyperhomocysteinemia. Six novel point mutations are described in patients with severe deficiency of MTHFR, along with their associated polymorphisms and clinical phenotypes. Of the two nonsense mutations (1762A-->T, 1134C-->G) and four missense mutations (1727C-->T, 1172G-->A, 1768G-->A, and 358G-->A), one was identified in the N-terminal catalytic domain, while the others were located in the regulatory C-terminal region. All four residues affected by missense mutations are conserved in one or more MTHFRs of other species. This report brings the total to 24 mutations identified in severe MTHFR deficiency, with two mutations identified in each of 22 patients.

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BACKGROUND: Cystinuria is a hereditary disorder that affects luminal transport of cystine and dibasic amino acids in kidney and small intestine. Three subtypes have been defined on the basis of urinary excretion of cystine in obligate heterozygotes. Mutations in the SLC3A1 gene have been associated with the Type I phenotype. METHODS: We investigated 20 cystinuria patients from Quebec (8 Type I/I, 9 Type I/III and 3 Type II/N) for mutations in SLC3A1. DNA was studied by Southern blotting and by the single strand conformation polymorphism (SSCP) protocol to identify mutations. Expression of mutations in Xenopus oocytes was performed to confirm the effect of missense mutations on cystine uptake. RESULTS: Six novel mutations (2 large deletions, a 2 bp deletion and 3 single bp substitutions) were identified on the Type I allele. Four missense mutations (T216M, S217R, R270L and I618M) were expressed in vitro; the first three changes significantly decreased uptake. CONCLUSIONS: Combined with our previous work, we have identified 15/16 mutations in SLC3A1 on Type I alleles in the eight Type I/I patients, but only one SLC3A1 mutation on the nine Type I alleles of the Type I/III patients. Therefore, we propose that the Type I phenotype could be caused by mutations in other, as yet unidentified cystinuria genes.

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BACKGROUND: Cystinuria patients may be classified into several subgroups based on the urinary phenotype of heterozygotes. However, the relative risk for nephrolithiasis and the prevalence of SLC3A1 mutations in these subgroups are unknown. METHODS: Urinary cystine excretion, age at onset of nephrolithiasis and nature of SLC3A1 mutations were assessed prospectively in 23 cystinuria patients identified primarily through the Quebec Newborn Screening Program. Probands were classified as to cystinuria subtype on the basis of parental urinary cystine excretion. RESULTS: For classical Type I/I cystinuria, both parents excrete cystine in the normal range and probands carry two mutations of the SLC3A1 gene in nearly every case. Between ages 1 to 7 years, mean cystine excretion was high (4566 +/- 480 microns cystine/g creatinine) and exceeded the theoretic threshold for solubility on 70% of visits. Four of eight Type I/I patients began forming stones in the first decade. Type I/III patients (N = 12) excreted less cystine (1544 +/- 163 mumol cystine/g creatinine), exceeded the threshold of urinary cystine solubility less frequently (22% of visits) and had no nephrolithiasis in the first decade; one formed a stone at age 16 years. Only one SLC3A1 mutation was identified in this group. Two Type II/N cystinuria children were identified. In these families, the same level of relatively high excretion (> 600 mumol cystine/g creatinine) was noted in two or three generations, but no SLC3A1 mutations were identified. CONCLUSIONS: Classical recessive Type I/I cystinuria is genetically and phenotypically distinct from the other subtypes (Type I/III and Type II/N) identified in our population.

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Sol gel process was applied for three different applications in environmental biotechnology: (1) thin, fluorescein diacetate-doped sol-gel film made possible epifluorescent microscopic examination of adsorbed Escherichia coli CN13 cells without additional staining: (2) Thiobacillus thiooxidans cell-free extract entrapped into sol-gel matrix displayed oxidative activity on H2S in liquid medium; and (3) two media (E. coli (EC) and sulfate-reducing bacteria (SRB)) were doped into sol-gel and used to enumerate environmental samples for E. coli and sulfate-reducing bacteria, by the most probable number (MPN) method. The comparison of the modified method with the standard enumeration method revealed very good correlation. The sol-gel MPN method is sensitive, saves times, and the substrate can be prepared and stored long-term at room temperature (up to 1 year).

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