Air pollution deposition on a roadside vegetation barrier in a Mediterranean environment: Combined effect of evergreen shrub species and planting density

Leaf deposition of PM_10-100, PM_2.5-10, PM_0.2-2.5 and of 21 elements was investigated in a roadside vegetation barrier formed by i) two evergreen shrub species (Photinia × fraseri, Viburnum lucidum), with ii) two planting densities (0.5, 1.0 plant m^-2), at iii) three distances from the road (2.0, 5.5, 9.0 m), at iv) two heights from the ground (1.5, 3.0 m), and on v) three dates (Aug, Sep, Oct). The presence of black and brown on-leaf PM_10-100 and their element composition were detected by microscopy and image analysis. Pollutant deposition was also measured using passive samplers at five distances from the road (2.0, 5.5, 9.0, 12.5, 19.5 m) in the area of the barrier and in an adjacent lawn area. V. lucidum had more PM_2.5-10 and PM_0.2-2.5 on leaves than P. × fraseri, while most elements were higher in P. × fraseri. Most pollutants decreased at increasing distances from the road and were higher at 1.5 m from the ground compared to 3.0 m. Higher planting density in P. × fraseri enhanced the deposition of PM_10-100 and PM_2.5-10, while in V. lucidum, the planting density did not affect the depositions. Black PM_10-100 decreased a long distance from the road and was entirely composed of carbon and oxygen, which was thus identified as black carbon from fuel combustion. The vegetation barrier had a higher deposition of most PM fractions at 5.5-12.5 m, while in the lawn area, depositions did not change. At 19.5 m, the PM_10-100 was 32% lower behind the barrier than in the lawn area. In conclusion, the vegetation barrier changed the deposition dynamics of pollutants compared to the lawn area. These results strengthen the role of vegetation barriers and shrub species against air pollution and may offer interesting insights for the use of new road green infrastructures to improve air quality.

The Role of Fluorine-18-Deoxyglucose (Fdg) Positron Emission Tomography (Pet) Whole Body Scan (Wbs) in the Staging and Follow-Up of Cancer Patients: Our First Experience

We report the results of FDG PET whole body scan in 75 cancer patients in whom tumor extent was defined by surgical, histological or cytological findings and clinical follow-up. Twenty-five had malignant lymphomas, 24 lung carcinomas, and 26 other types of solid tumors. Twenty-three patients were evaluated at disease onset, before therapy, and 37 at the moment of tumor recurrence; the remaining 15 patients were in complete remission after treatment and were taken as controls. Visual and quantitative PET results were compared with conventional imaging (US, CT scan and/or MRI, and Tc99m MDP bone scan).

In the 60 patients with active disease, PET as well as conventional imaging were able to locate the primary tumor in all 23 patients studied at disease onset. However, with regard to lymph node and distant metastases, PET provided the same information as conventional imaging in 31 cases (51.6%), but revealed further neoplastic foci in 29 cases (48.4%), 21 in lymph nodes and 8 at distant sites. The sensitivity of PET, in comparison with conventional imaging, was 100% versus 100% for the detection of the primary tumor, 97.6% versus 55.8% for the localization of node metastases, and 100% versus 55.5% for the visualization of distant metastases. The specificity, calculated in the group of 15 disease-free patients, was 100% for PET and 86.6% for conventional imaging. The therapeutic approach was modified in 12 patients (20%) on the basis of the PET results. Furthermore, in 14 cases (23.3%) with advanced disease, PET provided complete information on tumor spread, otherwise obtainable only by taking together the results of all other diagnostic procedures. Our data indicate a higher accuracy of FDG PET whole body scan compared to conventional imaging techniques in the evaluation of metastatic spread both at initial diagnosis and during follow-up, with an important impact on therapeutic decision-making. Moreover, by providing complete information on tumor spread in some cases, PET can become a profitable tool in terms of cost reduction.

Damage by Dichlorvos of Human Lymphocyte DNA

The action of dichlorvos (2.2-dichlorovinyldimethyl phosphate) was studied with a short-term in vitro system which utilizes human lymphocytes. The parameters studied were the action exerted by the pesticide on scheduled (semiconservative) and unscheduled (reparative) DNA synthesis measured as tritiated thymidine uptake. The results obtained show that dichlorvos affects semiconservative DNA synthesis, damages human lymphocyte DNA inducing low reparative synthesis, and interferes with DNA repair processes after damage exerted by ultraviolet rays.

Tissue Polypeptide Antigen (Tpa) Modifications in Hepatic Cirrhosis, Aggressive Chronic Hepatitis, Persistent Chronic Hepatitis, and in Minimal Pathology

A total of 104 patients with various liver diseases were studied. Hepatic biopsy was performed and the AST, ALT and TPA in serum were measured.

Higher levels of TPA, AST and ALT were found in CAH and LC, lower in CPH and MHP. High serum TPA values, usually suggesting the possibility of neoplasm, should be considered with attention. A follow-up with periodic TPA assays (in addition to AST and ALT) is suggested in patients with acute hepatitis, in order to predict further possible complications such as CAH and LC.

Serum Thymidine Kinase (TK) Evaluation in HIV Infection

Serum thymidine kinase (TK), measured using Prolifigen TK-REA, from AB Sangtec Medical, was investigated in 24 HIV seropositive patients without immunological alterations, 26 seropositives with immunological alterations, 125 LAS, 25 ARC, and 20 AIDS. Subjects with serological markers of prior EBV, HBV, and CMV infection were included but none with acute infectious mononucleosis or acute viral hepatitis. Serum TK was elevated from the beginning of the HIV infection, the seropositive stage, and more markedly afterwards during the course of the infection, with a close correlation with the stage.

TK also increased during AZT treatment, due to bone-marrow toxicity. On lowering the dosage or discontinuing the drug TK returned to basal levels.

Although the rise in serum may well not be correlated only with the HIV infection, it does add to the picture given by other clinical and/or laboratory methods. Serum TK can be a helpful laboratory test in the follow-up ofpatients with HIV infection, especially when serum levels are disproportionate to the stage, opportunistic infections, lymphoproliferative malignancies. In such cases bone-marrow toxicity due to treatment can be suspected.

Nature based solutions to mitigate soil sealing in urban areas: Results from a 4-year study comparing permeable, porous, and impermeable pavements

Soil sealing is one of the most pervasive forms of soil degradation that follows urbanization and, despite innovative pavements (i.e. pervious) are being installed in urban areas to mitigate it, there is little research on the effects of pervious pavements on soil water and carbon cycle and on the physiology of urban trees. The aim of this 4-year experiment was to assess the effects of three pavements, differing in permeability to water and gases, on some soil physical parameters, and on growth and physiology of newly planted Celtis australis and Fraxinus ornus. Treatments were: 1) impermeable pavement (asphalt on concrete sub-base); 2) permeable pavement (pavers on crushed rock sub-base); 3) porous design (porous pavement on crushed rock sub-base); 4) control (unpaved soil, kept free of weed by chemical control). Soil (temperature, moisture, oxygen content and CO₂ efflux) and plant (above- and below-ground growth, leaf gas exchange, chlorophyll fluorescence, water relations) parameters were measured. All types of pavements altered the water cycle compared to unpaved soil plots, but this disturbance was less intense in porous pavements than in other soil cover types. Porous pavements allowed both higher infiltration and evaporation of water than both pavers and asphalt. Reduction of evaporative cooling from soil paved with permeable and impermeable pavements contributed to significant soil warming: at 20cm depth, soils under concrete pavers and asphalt were 4 and 5°C warmer than soil covered by porous pavements and unpaved soils, respectively. Thus, enhancing evaporation from paved soil by the use of porous pavements may contribute to mitigating urban heat islands. CO₂ greatly accumulated under impermeable and permeable pavements, but not under porous pavements, which showed CO₂ efflux rates similar to control. Soil oxygen slightly decreased only beneath asphalt. Growth of newly planted C. australis and F. ornus was little affected by pavement type. Tree transpiration rapidly depleted soil moisture compared to the not-planted scenario, but soil moisture did not fall below wilting point (particularly in the deeper soil layers, i.e. 40-50cm) in any treatment. While C. australis showed similar leaf gas exchange and water relations in all treatments, F. ornus showed a depression in CO₂ assimilation and slight signs of stress of the photosynthetic apparatus when planted in soil covered with impermeable pavement. The effects of soil cover with different materials on tree growth and physiology were little, because newly planted trees have most of their roots still confined in the unpaved planting pit. Still, the reduction of soil sealing around the planting pit triggered the establishment of sensitive species such as ash. Further research is needed to assess the effects of different pavement types on established, larger trees.

Abstract OT3-05-01: Three-monthly dynamic evaluation of CEA and CA15-3 (followed by 18-FDG PET) vs usual practice in the follow-up of early breast cancer (BC) patients (pts): A prospective randomized trial (KRONOS-patient-oriented new surveillance study, Italy)

Background: Current guidelines for BC surveillance in asymptomatic pts recommend annual mammography and periodical physical examination. These recommendations arise from two trials conducted in the 1980's: since then no other randomized controlled trials (RCTs) have been conducted on BC follow-up. However our knowledge on BC biology, diagnosis of metastases and treatment has improved. The aim of this prospective RCT is to verify if the serial measurement of CEA and CA15.3 (followed by 18-FDG PET) can anticipate the diagnosis of breast cancer recurrence compared to control arm. If this intermediate end-point will be met a subsequent extension trial will investigate the impact of the earlier diagnosis of distant metastases on survival. Methods: Pts diagnosed with stage I-III BC, who underwent adequate surgery are eligible. Special histologies and low-risk cases according to St. Gallen criteria are excluded. We will include pts at the beginning of the follow-up after the conclusion of primary treatment (cohort 1), and pts that have concluded without relapse the first 5 years of follow-up (cohort 2). Eligible pts will be randomized in a 1:1 ratio to follow-up according to local practice (control arm) or to three-monthly serial dosing of CEA and CA15.3 and subsequent imaging studies (18-FDG PET) only in case of an increase of CEA and/or CA 15.3 greater than a critical difference (CEA +100% and/or CA15.3 +75%) compared to baseline (experimental arm). The following stratification factors will be used: node negative vs positive, HER2 negative vs positive, ER positive vs negative. Eight-hundred pts will be enrolled over 3 years. For such a calculation, we made the assumption of a 20% 5-year incidence of relapse. The target reduction of 3 months in restricted mean survival time (RMST) between the two arms implies a median time of diagnostic anticipation, conditional on having breast cancer recurrence, of 10 months. The follow-up will continue until 10 years from surgery. The first patient was enrolled on 23rd October 2014, up to now 434 pts have been enrolled. The present trial was approved by the Ethical Commitee of S. Orsola-Malpighi Hospital and is registered on clinicaltrials.gov (NCT02261389).

Citation Format: Zamagni C, Gion M, Mariani L, Stieber P, Quercia S, Rubino D, Bernardi A, Cacciari N, Fini A, Lenzi M, Minichillo S, Pizzirani C, Pagliaro M, Tomasini S, Barbieri E. Three-monthly dynamic evaluation of CEA and CA15-3 (followed by 18-FDG PET) vs usual practice in the follow-up of early breast cancer (BC) patients (pts): A prospective randomized trial (KRONOS-patient-oriented new surveillance study, Italy) [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr OT3-05-01.

Mucoadhesive Tablets for Buccal Administration Containing Sodium Nimesulide

The possibility of improving the flux of nimesulide across the buccal mucosa using the drug in the form of a sodium salt was investigated in our study. The salt form may increase to flux across buccal membrane, starting from a suspension; its lower permeation coefficient is compensated by a higher concentration gradient. The salt was inserted into a mucoadhesive tablet for buccal administration. The tablets were designed to prevent the loss of the drug into the saliva by means of a protective layer and placed on the area not in contact with the mucosa. Ten volunteers were used. The in vitro release from mucoadhesive tablets was examined through a porcine buccal mucosa, using a standard Franz cell, modified for present purposes. The advantages of a higher concentration gradient for the flux, related to a higher solubility of the salt, and to a sufficiently high permeation coefficient of the drug, despite the ionized form, could not be completely exploited, because the composition of the formulation destroys the chemical form of the drug.

Enhancement of Oleyl Alcohol Anti Tumor Activity through Complexation in Polyvinylalcohol Amphiphilic Derivatives

Oleyl alcohol was complexed with new amphiphilic polyvinylalcohol derivatives with the aim of increasing its aqueous solubility, thus improving bioavailability and favoring its antitumor activity. Water-soluble amphiphilic polymers were prepared by polyvinyl alcohol (PVA) substitution with oleyl chains through a succinyl spacer at 2% and 3% substitution degree. The complexes were obtained by spray-drying hydroalcoholic solutions of the substituted polymers and free oleyl alcohol at different weight ratios (3:1; 5:1; 10:1 w/w). The main physicochemical characteristics of the complexes were analyzed and correlated to the cytotoxic activity of oleyl alcohol toward tumor cell lines. The complexes strongly increased the aqueous solubility of oleyl alcohol and provided oleyl alcohol release in the presence of extractive conditions (simulating in vivo absorption). The complexes obtained by 10:1 polymer:fatty alcohol weight ratio offered higher release rates than the 5:1 and 3:1 ratios, respectively. Complexation also increased oleyl alcohol cytotoxicity toward tumor cells due to increased availability of the active molecule in the aqueous phase. Pure polymers were found to be biocompatible and no toxic effect was detected up to the highest concentration used in the present study (500 mu g/ml). The complexation of oleyl alcohol with the polymers analyzed here efficiently increased the availability of the fatty alcohol in aqueous environment. The enhanced cytotoxicity toward tumor cells of the complexed oleyl alcohol and the polymer biocompatibility make these amphiphilic PVA derivatives interesting candidates for soluble pharmaceutical formulations containing hydrophobic drugs whose therapeutic potential is often underestimated due to unsuitable levels of their aqueous solubilization.

Elaboration and “In Vitro” Characterization of 5-ASA Beads

The purpose of this research was to perform the design and in vitro evaluation of alginate beads containing 5-ASA in order to achieve an oral system that protects the drug until it reaches the colon. Alginate beads were prepared by the well-known ionic gelation reaction (Ca2+). The influence of the incorporation of several polymers (Eudragit FS 30D, Eudragit S100, and chitosan) in the initial formulation was studied. In all formulations, entrapment efficiencies of the drug higher than 70% were obtained. The scanning electron microscopy (SEM) study of beads showed homogeneous sizes and shapes in all cases. Finally, the release behavior of these polymeric beads were also studied and compared. The results indicated that Eudragit FS 30D (26%) showed the most favorable dissolution behavior in terms of achieving a controlled release of 5-ASA. To determine the mechanism of drug release from these beads, the Korsmeyer equation was applied. Qt/Qinfinity <0.9 can be described using a Higuchi model and Qt/Qinfinity=0.7 showed a zero-order release period. This formulation was assayed at other different pH values (pH=6; 6.8; 7.2) to assure that there is no release of 5-ASA until the system reaches the colon. No release was observed at pH 6.0. Release was very slow at pH 6.8; averages about 20% an hour at pH 7.2 and was complete within 4 hour at pH 7.4. So, these Eudragit FS beads exhibited interesting dissolution profiles for the therapy of colon pathologies.

Switching to anastrozole versus continued tamoxifen treatment of early breast cancer. Updated results of the Italian tamoxifen anastrozole (ITA) trial

BACKGROUND

Tamoxifen, for many years the 'gold standard' in the adjuvant setting for the management of endocrine sensitive early breast cancer, is associated with an increased risk of endometrial cancer and other life-threatening events. Moreover, many women relapse during or after tamoxifen therapy due to the development of resistance. This provided the rationale for a switching trial with anastrozole, the updated results of which are reported here.

PATIENTS AND METHODS

This trial investigated the efficacy of switching to anastrozole for women already receiving tamoxifen. After 2-3 years of tamoxifen treatment, postmenopausal, node-positive, ER-positive patients were randomized to receive either anastrozole 1 mg/day or to continue tamoxifen, 20 mg/day, giving a total duration of 5-years treatment. The primary end point was disease-free survival and secondary endpoints were event-free survival, overall survival and safety.

RESULTS

A total of 448 patients were enrolled. At a median follow-up time of 64 months (range 12-93), 63 events had been reported in the tamoxifen group compared with 39 in the anastrozole group [HR 0.57 (95% CI 0.38-0.85) P = 0.005]. Relapse-free and overall survival were also longer in the anastrozole group [HR 0.56 (95% CI 0.35-0.89) P = 0.01 and 0.56 (95% CI 0.28-1.15) P = 0.1]. However, the latter difference was not statistically significant. Overall more patients in the anastrozole group experienced at least one adverse event (209 versus 151: P = 0.000). However, numbers of patients experiencing serious adverse events were comparable (37 versus 40, respectively: P = 0.7).

CONCLUSIONS

Switching to anastrozole after the first 2-3 years of treatment was confirmed to improve event-free and relapse-free survival of postmenopausal, node-positive, ER-positive early breast cancer patients already receiving adjuvant tamoxifen.

Design and evaluation in vitro of controlled release mucoadhesive tablets containing chlorhexidine

This investigation deals with the development of buccal tablets containing chlorhexidine (CHX), a bis-bis-guanide with antimicrobial and antiseptic effects in the oral cavity, and able to adhere to the buccal mucosa to give local controlled release of drug. A mucoadhesive formulation was designed to swell and form a gel adhering to the mucosa and controlling the drug release into the oral cavity. Some batches of tablets were developed by direct compression, containing different amounts of hydroxypropylmethylcellulose (HPMC) and carbomer; changing the amount ratio of these excipients in formulations, it is possible easily modulate the mucoadhesive effect and release of drug. The in vitro tests were performed using the USP 26/NF paddle apparatus, a specifically developed apparatus, and a modified Franz diffusion cells apparatus. This last method allows a simultaneous study of drug release rate from the tablets and drug permeation through the buccal mucosa. Similar tests have also been carried out on a commercial product, Corsodyl gel, in order to compare the drug release control of gel with respect to that of the mucoadhesive tablet, as a formulation for buccal delivery of CHX. While the commercial formulation does not appear to control the release, the formulation containing 15% w/w methocel behaves the best, ensuring the most rapid and complete release of the drug, together with a negligible absorption of the active agent as required for a local antiseptic action in the oral cavity.

Modified polyvinylalcohol for encapsulation of all-trans-retinoic acid in polymeric micelles

All-trans-retinoic acid (ATRA) is now included in many antitumor therapeutic schemes for the treatment of acute promyelocytic leukaemia, Kaposi's sarcoma, head and neck squamous cell carcinoma, ovarian carcinoma, bladder cancer and neuroblastoma. Unfortunately its poor aqueous solubility hampers its parenteral formulation. To date, there is no parenteral formulation of ATRA commercially available and oral administration of ATRA is associated with progressively diminishing ATRA levels in plasma, which is related to induction of retinoic acid-binding protein and increased drug catabolism by cytochrome P-450-mediated reaction. An ATRA formulation, obtained by complexation of the drug into polymeric micelles, might be suitable for parenteral administration overcoming these unwanted effects. To this purpose we prepared an amphiphilic polymer by polyvinylalcohol (PVA) substitution with oleyl amine at 1.5% substitution degree (mol substituent per 100 mol hydroxyvinylmonomer) and evaluated its functional properties with regard to ATRA complexation. The substituted polymer displayed ability to interact with ATRA both in aqueous solution and in the solid state following spray-drying of drug-polymer hydro-alcoholic solutions. The spray-dried complexes rapidly dissolved in water providing high levels of ATRA solubilization as a function of the drug-polymer weight ratio. The complexes characterized by 1:5 drug-polymer weight ratio provided higher levels of ATRA solubilization than 1:3 and 1:10 drug-polymer weight ratios respectively. Pre-formed polymeric micelles in water equilibrated in the presence of excess solid ATRA provided the lowest levels of solubilization. The drug release from the complexes was very slow in PBS, indicating their suitability in antitumor drug targeting where a fundamental requirement is stability towards drug release for at least 24 h, corresponding to the average circulation time period of macromolecular carriers. The cytotoxicity studies against neuroblastoma cell lines outlined increased cytotoxicity of complexed ATRA with respect to free ATRA, likely due to the increased bioavailability of the hydrophobic drug from the complex. We conclude that ATRA entrapped into self-assembling polymer micelles may be a useful parenteral ATRA formulation overcoming the unwanted pharmacological mechanism that lead to acquired retinoid resistance.

Modified doxorubicin for improved encapsulation in PVA polymeric micelles

Polyvinylalcohol, partially substituted with lipophilic acyl chains, generates polymeric micelles in aqueous phase, containing a hydrophobic core able to encapsulate lipophilic drugs. Two types of polymers were obtained by conjugation of polyvinylalcohol with oleoyl or linoleoyl chains as pendant groups. The polymers, at a substitution degree of approximately 1%, are soluble in water and form polymeric micelles whose size increases with polymer concentration. Doxorubicin was hydrophobized, by linking an oleoyl chain via amide bond, to make the drug more similar to the substituted polymers and promote its encapsulation into the inner core of the micelles. The properties of the drug-polymer systems were evaluated in solution by dynamic light scattering technique and correlated to the physicochemical characteristics of the drug and the substituted polymers. Solubilization tests revealed that the similarity of the chain, in both the polymer and the drug, promotes better drug encapsulation in the oleoyl than linoleoyl derivative. The drug-polymer systems are stable in phosphate buffer saline (pH 7.4) at 37 degrees C, and the release of the drug is activated by the presence of the proteolytic enzyme pronase-E. The enzyme activated drug release and the size of the polymeric micelles, compatible with the pore dimensions of the tumor vessels, make these systems interesting for targeting lipophilic drugs to solid tumors, where the proteolytic enzyme concentration strongly raises with respect to the other body compartments.

A factor analysis for complex systems containing nimesulide

Binary systems containing Nimesulide and PEG 4000 were prepared by the melting method in the concentration range 3-25% w/w of the drug. The systems are homogeneous in the molten state, while, after cooling, two phases were formed of different density. They were manually separated and separately studied. Upper phases are richer in PEG 4000, while the lower ones contain the drug at levels even higher than those of the starting mixtures. The two phases were examined by DSC and UV techniques; high dissolution rates were observed with upper phases, while lower phases did not display improvement with respect to a physical mixture or micronized drug. With the aim to avoid phase separation, a third component was added to the binary system containing 5% w/w drug, during the melting. The ternary systems were prepared containing sodium dodecyl sulfate, triethanolamine, polysorbate 80, poloxamer, and cetomacrogol: a homogeneous phase was obtained only in two cases (with the addition of sodium dodecyl sulfate and triethanolamine), but only in the presence of triethanolamine dissolution rate was improved. Finally, a factor analysis was performed for complex systems containing a combination of the four additives, each one at two concentrations (1.25 and 2.5% w/w), to evaluate the optimum system in terms of both kinetic and composition parameters. Results suggest that additives affect mainly the physical aspect of the formulation rather than the kinetic behavior, which appears little improved only in a few cases.

Ultrasound-compacted and spray-congealed indomethacin/polyethyleneglycol systems

The product obtained by ultrasound (US)-assisted compaction was compared with a solid dispersion for systems containing polyethyleneglycols (PEGs) of different molecular weights and indomethacin (IMC), at the weight ratio 9:1, obtained by traditional melting and followed by a new US-assisted spray-congealing technique. US-discharge during compaction affects crystallinity of both IMC and PEG: pure IMC changes to an amorphous form and, when in mixture with PEG, partially dissolves in the excipient: this causes an increase of the dissolution rate of the drug. Differential scanning calorimetry (DSC) thermograms do not reveal any endothermic peak associated with the melting of the drug, while X-ray diffractograms show a loss of crystallinity of both IMC and PEG in the US-compacted granules. The extent of a back-crystallisation, which reduces the dissolution rate, as a function of the ageing of the material, depends on the type of the selected PEG. When a molten IMC/PEG mixture was transformed into microspheres by an US-assisted spray-congealing technique, the behaviour at dissolution almost recalls that of US-compacted granulates and some differences are briefly discussed.

Preparation and characterization by morphological analysis of diclofenac/PEG 4000 granules obtained using three different techniques

The steam granulation is a new wet granulation technique, which involves the use of steam water instead of traditional liquid water as granulation liquid. The aim of this work was to evaluate the possibility of using this new technique to prepare diclofenac-polyethylene glycol 4000 accelerated-release granules. Steam granules were prepared in a laboratory scale high-shear mixer, and their properties were then compared to those of granules, having the same composition, obtained by traditional granulation techniques (wet and melt granulation). The results showed that, selecting the proper process parameters, it was possible to obtain granules using all the three methods; however, the total process time was significantly shorter for steam granulation (30 min) in comparison to traditional wet granulation (70 min), due to the lower amount of used water. The morphological characterization of steam, water and melt granules, performed by scanning electron microscopy (SEM) and image analysis, revealed that steam granules had a more spherical shape and a larger surface area with respect to water and melt ones, suggesting a possible difference in dissolution behavior. Moreover, differential scanning calorimetry (DSC) and X-ray powder diffraction analysis evidenced the transformation of the drug from its originally crystalline form into the amorphous one. Finally, the in vitro dissolution tests showed an increased dissolution rate of the drug from the granules (in particular steam granules) in comparison to pure drug and physical mixture. In conclusion, the results of this study suggested that the steam granulation technique could be considered an interesting alternative to traditional wet granulation to improve the dissolution rate of diclofenac.

Alginate/chitosan particulate systems for sodium diclofenac release

Alginate/chitosan particles were prepared by ionic gelation (Ca2+ and Al3+) for the sodium diclofenac release. The systems were characterized by electron microscopy and differential scanning calorimetry. The ability to release the active substance was examined as a function of some technological parameters and pH of dissolution medium. The release of sodium diclofenac is prevented at acidic pH, while is complete in a few minutes when pH is raised up to 6.4 and 7.2. The alginate/chitosan ratio and the nature of the gelifying cation allow a control of the release rate of the drug. The release mechanism was briefly discussed.

Diclofenac salts. I. Fractal and thermal analysis of sodium and potassium diclofenac salts

Sodium and potassium diclofenac salts form hydrates when crystallized from water; the sodium salt contains four crystallization water molecules, while the potassium salt precipitates as a dihydrate. Crystallization from organic solvents occurs with a change of the crystal habit. The fractal dimension of the particle surface of both salts obtained from water is low and is in agreement with the formation of smooth and regular surfaces during crystallization. The fractal dimension for dissolution is relatively high and comparable for hydrate and anhydrate forms of both salts, and the result was interpreted as being due to the surfactant behavior of diclofenac anions. Thermograms of both salts show a couple of endotherms in the range 30-100 degrees C, which disappear when the salts have been previously heated at 100 degrees C, but slowly reappear when the anhydrate forms are stored in a humid environment. Both salts present a complex exotherm of decomposition at 284 and 314 degrees C, respectively. The results are briefly discussed with regard to the formulations of the anti-inflammatory agent diclofenac.

Improvement of the synthesis of diphenylmethyl 7beta-(o-hydroxy)benzylideneamino-3-hydroxymethyl-3-cephem-4-carboxylate

The title product (I) is synthesized currently from 7-aminocephalosporanic acid, and diphenyldiazomethane (DDM) is used as a protective reagent of the acid function for further reactions. When DDM was prepared from benzophenone hydrazone by reaction with chloramine T, it was resulted impure by p-toluenesulfonamide, formed as side product, which cannot be removed during the final purification step carried out according to the literature procedure. Two simple methods are proposed here to obtain I with the suitable degree of purity necessary for a drug.

Channeling agent and drug release from a central core matrix tablet

A new oral dosage form for controlled and complete release of drug after a predetermined lag time is described. The system, designed to exploit the relatively constant small intestine transit time, consists of a drug-containing core coated with a polymeric matrix formed by a channeling agent (NaCl, mannitol, and Emdex) and an inert polymer (Eudragit RS100). The lag time was found to be dependent on type and particle size of the channeling substances used. Also, rheological properties of the binary mixtures (channeling substance--polymer) can affect the lag time periods. On the other hand, the release kinetics were found to be influenced significantly by excipient type and particle size. Results obtained from in vitro dissolution testing demonstrated that this device potentially could be used to deliver drugs orally for up to once-a-day dosing at controllable rates.

Interaction between indomethacin and heavy metal ions in aqueous solution

The interaction between indomethacin anions and heavy metal ions, such as cadmium, zinc and copper(II) ions, was studied in aqueous solution by polarographic techniques. Indomethacin anions form complexes with these heavy metal ions: the complex formed with cadmium ions is sparingly soluble, while more soluble and also stronger complexes are formed with zinc and copper(II). At high concentrations, where indomethacin anions undergo self-aggregation, these last compounds are solubilised. This property is briefly discussed and compared to that of bile salts. In the presence of calcium ions, indomethacin forms a poorly soluble salt and no evidence was detected for the formation of complex species.

Percolation thresholds in ultrasound compacted tablets

Twenty matrix systems with different KCl content (as drug model, from 10 to 90% w/w) and Eudragit RS-PM (as inert excipient) were prepared using an ultrasound-assisted press and a traditional eccentric machine. The release behavior from both types of matrices was examined; the kinetic parameters for the release (intrinsic dissolution) and the technological properties of the final tablets (total porosity) were used to estimate the percolation threshold for the drug model and the excipient in both systems. For the systems compacted by ultrasound (US) the estimated value for the excipient percolation threshold ranges from 13.4 to 20.2% v/v (lower than that found for traditional tablets), that agrees with a continuum percolation model suggesting the presence of a continuum phase inside the tablet. This depends on a thermoplastic deformation of Eudragit RS-PM under ultrasound, that destroyed the particulate system of the excipient and transform it into a continuum medium. The percolation threshold for KCl ranged from 58.6 to 61.0% v/v for US and from 26.7 to 42.2% v/v for the traditional tablets. The higher value for ultrasound compacted tablets can be explained by the difficulty of KCl to outcome from a matrix containing insoluble phase that surrounds KCl crystals.

A rapid procedure to prepare cefotaxime

A rapid procedure is reported for the synthesis of cefotaxime, by acylation of the 7-amino cephalosporanic acid with the 2-mercaptobenzothiazolyl thioester of (Z)-2-[2-aminothiazol-4-yl]-2-methoxyimino acetic acid (MAEM) that is a commercial reagent. The reaction was carried out at room temperature for 1 h, obtaining 95% yield. 2-Mercaptobenzothiazole was recovered as a side-product with a high purity and yield. The proposed method differentiates from those reported previously for a shorter time and very mild reaction condition, as well as for a ready for use reagent.

Synthesis of (Z)-2-(2-formamido-4-thiazolyl)-2-(substituted alkoxyimino) acetic acids

(Z)-2-(2-formamido-4-thiazolyl)-2-(substituted alkoxyimino) acetic acids were synthesized by a new method based on the following sequence of reactions: treatment of the tert-butyl acetoacetate with sodium nitrite, alkylation of the oxime formed with an appropriate alkyl halide, halogenation of methyl alpha-keto group and simultaneous cleavage of tert-butyl ester with sulfuryl chloride, protection of the obtained acid function with diphenyldiazomethane, formation of the 2-aminothiazole ring by the Hantzsch method with thiourea, formylation of the amino group and selective final cleavage of the diphenylmethyl ester by treatment with trifluoroacetic acid and anisol. The developed procedure allows the synthesis of (Z)-2-(2-formamido-4-thiazolyl)-2-(substituted alkoxyimino) acetic acids, with an ester function in the alkoxyimino group employing a simple method and obtaining higher yields in comparison with the habitually used classic method.

Formation of ion-pairs in aqueous solutions of diclofenac salts

In this work we studied the ability of the diclofenac anion to form ion-pairs in aqueous solution in the presence of organic and inorganic cations: ion-pairs have a polarity and hydrophobicity more suitable to the partition than each ion considered separately and can be extracted by a lipid phase. The cations considered were those of the organic bases diethylamine, diethanolamine, pyrrolidine, N-(2-hydroxyethyl) pyrrolidine and N-(2-hydroxyethyl) piperidine; the inorganic cations studied were Li(+), Na(+), K(+), Rb(+), Cs(+). Related to each cation we determined the equilibrium constant (K(XD)) for the ion-pair formation with the diclofenac anion in aqueous solution and the water/n-octanol partition coefficient (P(XD)) for each type of ion-pair formed. Among the alkali metal cations, only Li(+) shows some interaction with the diclofenac anion, in agreement with its physiological behaviour of increasing clearance during the administration of diclofenac. The influence of the ionic radius and desolvation enthalpy of the alkali metal cations on the ion-pair formation and partition was briefly discussed. Organic cations promote the formation of ion-pairs with the diclofenac anion better than the inorganic ones, and improve the partition of the ion-pair according to their hydrophobicity. The values of the equilibrium parameters for the formation and partition of ion-pairs are not high enough to allow the direct detection of their presence in the aqueous solution. Their formation can be appreciated in the presence of a lipid phase that continuously extracts the ion-pair. Extraction constants (E(XD)=P(XD) times K(XD)) increase passing from inorga to organic cations. This study could help to clarify the mechanism of the percutaneous absorption of diclofenac in the form of a salt, a route where the formation of ion-pairs appears to play an important role.

Description and preliminary evaluation of a new ultrasonic atomizer for spray-congealing processes

A new atomizer that operates with ultrasonic energy is described. This apparatus is intended to obtain microparticulate drug delivery systems through spray-congealing or spray-drying technologies. In this work, some experimental results are reported on model systems submitted to spray-congealing. The formulations under examination contained theophylline and fenbufen as model drugs and stearic acid, carnauba wax, Cutina HR(R) and Compritol 888 ATO(R) as low melting excipients. Non-aggregate and spherical-shaped microparticles were obtained with all the materials tested; moreover, they had smooth surface and good flowability. The particle sizes depend on the amount of drug present and in each case the maximum size value of the distribution frequency was found to be 375 mu. In vitro release of the drug depends on its solubility and on the excipient lipophilicity. The results suggest that the ultrasound-assisted atomizer could be proposed as a possible alternative to traditional atomizers used for spray-congealing in the pharmaceutical field.

Dehydration and rehydration of a hydrate diclofenac salt at room temperature

The salt diclofenac/N-(2-hydroxyethyl) pyrrolidine crystallizes from water as a dihydrate, while it precipitates from organic solvents anhydrously: the two salts have different crystal structures. Dehydration of the dihydrate salt was carried out in a desiccator over silica gel at room temperature: the process occurs with the retention of the crystal structure. Slight changes observed in the diffractograms suggest, that soon after dehydration, a phase transition starts, slowly due to the low temperature of the process. The reaction was followed determining the loss of weight as a function of time and by thermal analysis, since the dihydrate and the dehydrate forms have different thermograms, but similar diffractograms. The reaction was complete after 24 h. The analysis of the experimental data suggests a kinetic process related to a one-dimensional diffusion of the crystallization water molecules outwards the solid particles. At room temperature, the dehydrate material rapidly back-absorbs the two molecules of crystallization water from the atmosphere moisture. The interaction with water of the different forms of the salt was discussed as a function of their solid structures as well as of the complex equilibria present in aqueous solution: these can explain previous apparently anomalous results.

Effect of the temperature on a hydrate diclofenac salt

The salt Diclofenac/N-(2-hydroxyethyl) pyrrolidine when crystallizes from water forms a di-hydrate, which looses the crystallization water molecules on heating or in the presence of silica gel, undergoing a phase transition. The two processes were followed at room temperature, at 40 and 50 degrees C by thermal analysis and analyzing the dimensional parameters obtained by scanning electron microscopy as a function of the changes occurring in the solid state. The fractal dimension of the particle surface (DS) was determined for the di-hydrate, the anhydrate and the anhydrous forms: DS values are close together suggesting that the processes modify only slightly the external morphology of the particles. The reactive dimension (DR) to dissolution suggests that the salt after the thermal treatment has a dissolution behaviour identical to that observed for the salt obtained from organic solvents. The two processes de-hydration and phase transition can be carried out at relatively low temperature, suggesting an important pathway to obtain the anhydrous form starting from the di-hydrate one.

[Prevalence of goiter and urine iodine in a school population in an area of the Bolognese Apennines]

We evaluated goiter prevalence and urinary iodine excretion (UIE) in schoolchildren living in three villages of the Appennines in the Bologna district-Castel d'Aiano (CA), Gaggio Montano (GM) and Pietracolora (PC). 175 age-matched schoolchildren living in the urban area of Bologna were considered as control group. In the control area the presence of goiter was documented in 11 out of 175 subjects (6.3%). In the mountain area the presence of goiter was documented in 42 out of 233 subjects (18%) (p < 0.0001 vs control area). In the urban control area the UIE was 159 micrograms/l (median; range 19-298). In the mountain area the UIE was 119 micrograms/l (median; range 10-286) (p < 0.001 vs control area). We observed the highest prevalence of goiter and UIE levels < 100 micrograms/l only in the village of PC, which is still characterized by geographical isolation and rural economy.

Effects of ultrasound-assisted compaction on Ketoprofen/Eudragit S100 mixtures

Ketoprofen alone and in binary mixtures with Eudragit S100 was compacted by an ultrasound-assisted (US) tableting machine at an energy ranging from 50 to 400 J. The final material was analysed by TLC and HPLC: no decomposition product of the active agent was found. IR spectra and HSM revealed the absence of any interaction between the two components. Thermal analysis (DSC) evidenced that ketoprofen inside the mixtures was transformed into an amorphous state, documented by the decreasing of the DeltaHfus as the Eudragit/ketoprofen ratio increases and as US energy increases. While pure ketoprofen recovers its crystalline state quickly after the US treatment, the presence of Eudragit was found to slow down or possibly to prevent the regeneration of the crystallinity.

Study of the antioxidant effect of several selenium and sulphur compounds

Four selenium derivatives (sodium selenate, sodium selenite, selenourea and selenomethionine) and the sulphur analogues (sodium sulfate, sodium sulfite, thiourea and methionine), together with urea, were examined by means of polarography to study their reactivity towards superoxide ion O2. In order that experimental results could be applied to physiological conditions and to control the electroreduction of oxygen, most reactions were carried out in model systems (in the presence and in the absence of triphenyl phosphine oxide and at increasing pH) which are briefly described and discussed. Sodium sulfite and thiourea react with molecular oxygen; selenourea originates an anodic wave, although under other pH conditions. Other compounds (selenate, selenite, seleno-methionine and methionine) display an interesting antioxidant capacity because they catalyse the disproportion of the superoxide ion, as documented by the increase in the limiting current. Methionine appears to be particularly efficient in this respect, since it retains its catalytic ability in a poorly protic environment. Experimental results support the view that exogenous compounds, administered for particular purposes, can display unanticipated, and sometimes positive, side effects.

Myocardial perfusion, glucose utilization and oxidative metabolism in a patient with left bundle branch block, prior myocardial infarction and diabetes

A diabetic patient affected by insulin-dependent diabetes, significant stenosis of left anterior descending (LAD) coronary, thrombolyzed myocardial infarction and complete left bundle branch block (LBBB) was examined by PET. Myocardial perfusion, glucose utilization and oxidative metabolism were evaluated by 13N-ammonia, 18F-fluorodeoxyglucose (FDG) and 11C-acetate, respectively. Despite severe damage in 18F-FDG uptake in the septum, with a septum-to-lateral ratio (S/L R) equal to 0.38, the oxidative metabolism in this area, evaluated quantitatively by dynamic acquisition, was relatively preserved (S/L R = 0.82), with a distribution similar to perfusion (S/L R = 0.87). These data reveal selective damage in glucose utilization in the septum in LBBB, unrelated to perfusion reduction and with preserved oxidative metabolism. Moreover, our experience could suggest an overestimation of the necrotic area by 18F-FDG in LBBB patients.

Interaction of iron(II) with bile salts

Iron(II) ions react with small aggregates of cholate, glycocholate, chenodeoxycholate, and deoxycholate to form soluble and colloidal compounds. Taurocholate under conditions used does not react with the Fe2+ ion. Small aggregates of dihydroxy bile salts (predominating in the premicellar region, at concentrations of the bile salt above 1 mmol dm-3) have a larger affinity for Fe2+ compared to those formed from cholate anions. In their interactions with small aggregates of cholate anions, the Fe2+ ion shows an affinity comparable to that of Cu2+ and Cd2+ and somewhat larger than that of Zn2+. Small aggregates of cholate show a higher ability to mask Fe2+ than those of taurocholate and glycocholate. Interaction of glycocholic acid anions with Fe2+ ions is sufficient to prevent iron(II) precipitation.

Fractal analysis of beta-cyclodextrin-indomethacin particles compacted by ultrasound

An association between indomethacin and beta-cyclodextrin (beta-CD) was obtained by compacting a 1:2 molar physical mixture by ultrasound. The product prepared by this technique was compared with the initial physical mixture and with materials having the same composition but prepared by a simple compaction and kneading process. The samples examined by scanning electron microscopy revealed morphological differences related to the methods of preparation. In particular the material obtained by ultrasound had a smooth surface and on milling produced particles of uniform size; moreover EDAX analysis (energy dispersion analysis by X-rays) also revealed a homogeneous distribution of the two components in each particle examined. Surface fractal dimension of the surface of these particles is very low, suggesting the presence of a regular and smooth surface whereas the sample obtained by kneading had a higher value. The reactive dimension related to dissolution was much higher than the corresponding surface dimension in all cases and had comparable values for all samples regardless of the techniques used. This behavior was attributed to the hydrophilicity of beta-CD, which levels the differences during dissolution and which could be originated by surface imperfections. Experimental results suggested that the material obtained by ultrasound had a dissolution rate comparable to that measured with the kneaded material. The use of ultrasound, however, can both reduce the production time and improve the homogeneity of the association between indomethacin and beta-CD.

Interaction between trace elements: selenium and cadmium ions

The interaction between several inorganic and organic selenium-containing compounds (selenite, selenate, selenourea and selenomethionine) and Cd2+ ions was studied by polarography. The changes in polarographic currents and half-wave potentials of the metal ions as a function of the Se-derivative concentration were followed. Experimental results suggest a different behaviour depending on the oxidation state of selenium. Any interaction between selenate and Cd2+ ions can be excluded. In the case of selenite, the presence of complexes in the solution was demonstrated. The shift in the Cd2+ reduction half-wave potential when a relatively high concentration of selenourea is present indicates formation of complexes, while the decrease in limiting current reflects the limited solubility of the complex itself. Results concerning selenomethionine suggest a very weak interaction with Cd2+ ions. These preliminary results are discussed in comparison with previous findings in cellular systems and may prove helpful in understanding cadmium ion toxicity and the in vivo altered distribution of various metal ions following the administration of selenium compounds.

Fractal analysis of sodium cholate particles

A fractal analysis was carried out on the powder particles of two samples of sodium cholate. A commercial sample had very irregular particles agglomerated, and accordingly the fractal dimension of the surface was 2.98, suggesting a noteworthy roughness of the particle surface; scanning electron microscopy showed that this was due to irregularities caused by a disordered agglomeration of very small particles, resulting in larger particles showing polygonal and smooth but limited facets. A second sample was obtained by recrystallization from ethanol of the commercial sodium cholate and contained large and regular particles, with very smooth surfaces. The fractal dimension therefore was accordingly low. Despite these differences, the two samples had similar, high reactive dimension values to dissolution (2.96 and 2.76, respectively), suggesting that the surfactant behavior of sodium cholate is an important parameter in driving the dissolution of the solid particles and leveling the surface defects.