Preparation of Co2+/ZSM5 Catalysts by Solid-State Reaction: Influence of the Precursor on Cobalt Speciation

Co2+/ZSM5 catalysts (Co/Al = 1, overstoichiometric ratio) have been prepared by solid-state reaction at 500 °C in argon from H-ZSM5 and four Co(II) precursors: formate, nitrate, chloride and acetate. Co3O4 particles supported by the zeolite grains are the only cobalt-containing phases detected when formate is used. When cobalt nitrate is the precursor, Co3O4 particles appear to be independent from the grains. A fraction of cobalt has nevertheless migrated into the zeolite; this is linked with [Co(H2O)6](NO3)2 low melting point and wetting of the zeolite grains by the molten salt at the beginning of the thermal treatment. Catalysts prepared from cobalt chloride contain both nanometric Co3O4 particles on the support grains and cobalt ions inside the zeolitic channels. Ion exchange is possible, at least partly, due to the fact that unlike nitrate and formate, cobalt chloride has not decomposed before reaching the temperature at which the exchange process is activated. This process is chemically driven by the release of HCl in the gas phase. Finally, the major phase detected when cobalt acetate is the precursor is a poorly organized cobalt phyllosilicate surrounding zeolite grains. Acetate ions attack the zeolitic framework from outside during the solid-state reaction; cobalt ions are inserted in the silicate matrix and progressively migrate deeper in the grains upon thermal activation.

[Late neurotoxicity after nasopharyngeal carcinoma treatment]

PURPOSE

A retrospective analysis of risk factors for late neurological toxicity after nasopharyngeal carcinoma radiotherapy.

PATIENTS AND METHODS

Between 1993 and 2004, 239 patients with non metastatic nasopharyngeal carcinoma were treated by radiotherapy associated or not to chemotherapy. Radiotherapy was delivered with two modalities: hyperfractionated for 82 patients and conventional fractionation for 157 patients. We evaluated the impact of tumour stage, age, gender, radiotherapy schedule and chemotherapy on neurological toxicity.

RESULTS

After a mean follow-up of 107 months (35-176 months), 21 patients (8.8%) developed neurological complications, such as temporal necrosis in nine cases, brain stem necrosis in five cases, optics nerve atrophy in two cases and myelitis in one case. Five- and ten-year free of toxicity survival was 95 and 84% respectively. Young patients had greater risk of temporal necrosis, and hyperfractionated radiotherapy was associated with a significantly higher risk of neurological complications (14.6% vs 5.7%, p=0.02). On multivariate analysis, hyperfractionation and age were insignificant.

CONCLUSION

Late neurological toxicity after radiotherapy for nasopharyngeal carcinoma was rare. Younger age and hyperfractionation were considered as risk factors of neurological toxicity in our study.

Chronic neck pain and vertigo: Is a true balance disorder present?

OBJECTIVE

We sought to establish whether chronic neck pain patients suffering from vertigo and instability have true balance disorders.

PATIENTS AND METHODS

Ninety-two patients having suffered from chronic neck pain for at least 3 months were enrolled in the present study. Patients with a history of neck trauma or ear, nose and throat, ophthalmological or neurological abnormalities were excluded. The patients were evaluated in a clinical examination (neck mobility) and a test of dynamic and static balance on the Satel((R)) platform in which mediolateral (Long X) and anterior-posterior deviations (Long Y) were monitored. Our patients were divided into three groups: a group of 32 patients with neck pain and vertigo (G1), a group of 30 patients with chronic neck pain but no vertigo (G2) and a group of 30 healthy controls.

RESULTS

All groups were comparable in terms of age, gender, weight and shoe size. Osteoarthritis was found in 75% and 70% of the subjects in G1 and G2, respectively. Neck-related headache was more frequent in G1 than in G2 (65.5% versus 40%, respectively; p=0.043). Restricted neck movement was more frequent in G1 and concerned flexion (p<0.001), extension (p<0.001), rotation (p<0.001), right inclination (p<0.001) and left inclination (p<0.001). Balance abnormalities were found more frequently in G1 than in G2 or G3. Static and dynamic posturographic assessments (under "eyes open" and "eyes shut" conditions) revealed abnormalities in statokinetic parameters (Long X and Long Y) in G1.

CONCLUSION

Our study evidenced abnormal static and dynamic balance parameters in chronic neck pain patients with vertigo. These disorders can be explained by impaired cervical proprioception and neck movement limitations. Headache was more frequent in these patients.

Investigations on the leaf surface ultrastructure in grapevine (Vitis vinifera L.) by scanning microscopy

Several Scanning microscopy techniques were used to investigate the leaf surface ultrastructure in the local "Razegui" grapevine cultivar (Vitis vinifera L.). Conventional scanning electron microscopy performed on glutaraldehyde-fixed samples allowed observation of well-preserved epidermal cells with an overlaying waxy layer. At a high magnification, the waxy layer exhibited crystalline projections in the form of horizontal and vertical platelets. Also, to avoid eventual ultrastructural alterations inherent in the use of solvents during sample preparation, fresh leaf blade samples were directly observed by environmental scanning electron microscopy. A classical image of convex living epidermal cells was observed. At 2400x magnification, epicuticular waxes exhibited a granular structure. However, high-magnification images were not obtained with this device. The atomic force microscopy (AFM) performed on fresh leaf blade samples allowed observation of a textured surface and heterogeneous profiles attributed to epicuticular wax deposits. AFM topography images confirmed further, the presence of irregular crystalloid wax projections as multishaped platelets on the adaxial surface of grapevine leaf.

[Neurofibromatosis type 1 revealed by malignant peripheral nerve sheath tumor]

Neurofibromatosis type 1 or Von Recklinghausen's disease is an affection with variable clinical expression. Malignant transformation is rare and dangerous.

OBJECTIVE

The aim of this work is to study diagnostic criterias as well as treatment of this malignant transformation.

CASE REPORT

Sixteen years old patient presented with gradually progressive basicervical mass without compression nor dysthyroidy signs. Physical examination revealed a painless, hard and well limited mass measuring 4 cm. It was located in front of sternal manuhrium and associated to multiples "café au lait" spots, iris Lisch nodules and generalized neurofibromas. This mass was excised by cervical surgery. The histological exam concluded to a low grade malignant peripheral nerve sheath tumour Unfortunately despite a larger reoperation including resection of the manubrium, the limit of this excision were not safe. Early recurrence was observed, although treated by surgery, chemotherapy and radiotherapy, the patient died by mediastinal invasion.

[Cervical spondylodiskitis revealed by retropharyngeal abscess]

INTRODUCTION

Spondylodiskitis is rare in the cervical vertebrae. We report a case of cervical spondylodiskitis revealed by a retropharyngeal abscess caused by a pyogen agent. The aim of our work was to shed light on the diagnosis and therapeutic difficulties of spondylodiskitis associated with a retropharyngeal abscess.

CASE REPORT

A 70-year-old patient was admitted to the emergency department for a progressive laryngeal dyspnoea of 3 months duration. Clinical examination showed severe dyspnoea. Oropharynx and pulmonary exams were unremarkable. Failure of medical treatment led to the performance of an emergency tracheotomy after which the patient developed a flaccid quadriparesis. Medullar MRI revealed a spondylodiskitis with medullary compression and a retropharyngeal abscess. Surgical biopsy concluded to a pyogen osteitis. Treatment in the form of antibiotics and cervical immobilisation was instituted. Evolution was marked with septicaemia, multiple organ failure and ionic disturbance leading to death.

COMMENTS

Cervical spondylodiskitis is rare. Its revelation by retropharyngeal abscess is also rare. MRI is the tool of choice for diagnosing discovertebral infections and its prevertebral extensions. Treatment is medical and surgical.

TiIV Exchanged K10-Montmorillonite: Characterisation and Catalytic Properties in Liquid-Phase Sulfide Oxidation

Titanium-containing K10 has been synthesised and characterised by X-ray diffraction, UV-visible reflectance, solid state NMR spectroscopy, N2 nitrogen adsorption at 77K and chemical analysis. Two different titanium species have identified with a high dispersion in K10. The first is in an isolated penta- and hexa-coordinated state and the second is in the form of polymerised hexacoordinated species, which contains Ti-O-Ti bonds. These titanium species were found to be the catalytic sites that readily interact with oxidant to offer an active and selective catalytic system for the oxidation of sulfides. This catalytic system was studied in the asymmetric oxidation of methyl phenyl sulfide, using different types of chiral modifier, and gives excellent conversion and sulfoxide selectivity, together with a significant enantioselectivity in the range of 16–18% ee with (R)-binol.

Efficient procedure for grapevine embryogenic suspension establishment and plant regeneration: role of conditioned medium for cell proliferation

An efficient system for the establishment and multiplication of highly prolific embryogenic cell cultures of grapevine (Vitis sp.) was developed. Using anther-derived pro-embryogenic masses as starting material, cell suspensions of different grapevine cultivars (Tempranillo, Cabernet-Sauvignon) and rootstocks (Kober 125 AA, Kober 5 BB, 110 Richter) were initiated in liquid medium containing NOA (1.0 mg l(-1)) and BAP (0.25 mg l(-1)) as growth regulators. Conditioned medium was recovered and utilised for establishing new, highly totipotent cell cultures. The suspensions obtained, showed embryogenic competence resulting in somatic embryo induction and subsequent plant regeneration. In this study, a simplified establishment procedure for grapevine embryogenic cell suspension allowing the fast multiplication of embryogenic material is described. Evidence for the promoting effect of the protein fraction derived from conditioned medium, on cell proliferation was found. In bioassays, addition of ss-D: -GlcY affect cell proliferation suggesting that arabinogalactan proteins are required for growth processes in grapevine cell cultures.

Prognostic factors in metastatic nasopharyngeal carcinoma

BACKGROUND

The current retrospective study aimed to identify some determinants of survival in metastatic NPC.

METHODS

The study concerned 95 patients with metastatic nasopharyngeal carcinoma treated between 1993 and 2001. Statistical comparison between patients subgroups survival was carried out employing the log-Rank test (statistical significance was defined as p<or=0.05). Multivariable analysis was performed using the Cox model (p<or=0.05 was used as the cut-off value of statistical significance). Factors that were considered included: age group(<or=45 years or>45 years and<or=25 years or>25 years), gender, performance status at diagnosis of metastatic disease (PS 0-1 or 2-3), time of metastasis diagnosis(at presentation or later), number of metastatic sites (single or multiple), specific metastatic sites(bone, liver, lung, distant nodes), number of bone metastasis (single or multiple), disease free survival (DFI) (<or= or >6 months), prior chemotherapy, radiotherapy of metastatic sites.

RESULTS

Negative prognostic factors in univariate analysis were: poor PS (>or=1), multiple metastatic sites, multiple bone metastasis, previous chemotherapy, visceral or node metastasis and non irradiated metastasis. Poor PS, multiple metastatic sites, and prior chemotherapy were independently significant negative prognostic factors in multivariable analysis.

CONCLUSIONS

In this study we identified new prognostic factors in univariate and multivariate analysis. A regular and careful follow-up of patients treated for NPC is then recommended in order to detect early metastatic dissemination (with minimal localizations) while patients have still a good PS.

[Pyogenic abscess of the breast: clinical and therapeutic aspects]

OBJECTIVE

The goal of this retrospective work was to study the clinical aspects and the principles of management of the abscess of the breast in order to determine a convenient and recent therapeutic attitude.

PATIENTS AND METHODS

Our retrospective survey concerns 114 cases of breast abscess collected in a surgery department over a period of 14 years, from 1990 to 2003. All patients have been operated and the diagnosis confirmed through the operation. The puerperal abscesses have been noted in 31 cases.

RESULTS

One hundred and four women and ten men were concerned, with a sex-ratio of 0.1. The medium age was 33 years old for the women and 42 years for the men. The diagnosis was based on the clinical criteria, confirmed by the ultrasonography in 11 cases out of 16 and by the mammary puncture in 15 cases out of 22. Two non-puerperal abscesses have revealed an infiltrating canal carcinoma. The Staphylococcus aureus was the germ the most frequently met, concerning 8 cases out of 16. The surgical biopsies carried out in 52 cases revealed a fibrocystic mastopathy in six cases, a canalar ectasia in two cases and an infiltrating canalar carcinoma in two cases. The surgical treatment, performed in any case, was associated to an anti-staphylococcus antibiotherapy. The recurrence of the abscess has been observed in four cases.

DISCUSSION AND CONCLUSION

The frequency of pyogenic abscess of the breast, particularly the puerperal abscesses, has considerably decreased. The non-puerperal abscesses often pose a differential diagnosis problem with the very aggressive inflammatory cancers. The percutaneous ultrasonography guided drainage must be proposed in first intention to treat the abscesses of the breast. However, surgical treatment is still valid with an abscess either relapsing or chronic, or else the failure of the non-operative processes.

Occurrence of pathogenic fungal species in Tunisian vineyards

Mycotoxins are secondary metabolites produced by filamentous fungi detected in food, such are grapes. OTA was evaluated in ten handle musts from different Tunisian vineyard. This mycotoxin was found at levels 1.1 mug/L to 4.3 mug/L. A survey was conducted to assess the contamination of the Tunisian vineyard with pathogenic fungal species, in particular those responsible of the OTA production. The results were evaluated for the first time in parcels cultivated in the North, in the Centre and in the South of the country. Italia Muscate and Superior Seedless varieties were concerned at three developmental stages of the berry, setting, veraison and maturity. Carigon variety was used as positive control for musts contaminating by OTA. The main fungal species isolated were Aspergillus spp. (33.32%), Botrytis cinerea (23.32%), Alternaria spp. (12.80%), Cladosporium spp. (10.59%) and Penicillium spp. (8.3%). The isolates of the Aspergillus genus were identified as Aspergillus niger aggregate (77%), Aspergillus carbonarius (15%) and Aspergillus flavus (8%). Their presence was characterized by a significant decrease in the Centre during the veraison and a slight increase in the North and the South during the maturity stage. Furthermore, when comparing Superior Seedless and Italia Muscate cultivated in the same area, the aspergilli were particularly less abundant at the setting stage in the case of Superior Seedless. There is no correlation between the OTA amount in musts and the contamination by Aspergillus species in different vineyards and for grape varieties studied.