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Fluoxetine (d,l-N-methyl-3-phenyl-3-[(alpha,alpha,alpha,-trifluoro-p-tolyl)oxy]propyl-amine) is the parent drug of the SSRI (selective serotonin reuptake inhibitor) antidepressant class. After administration, fluoxetine is subject to hepatic metabolism by cytochrome P450 enzymes, whose main product is the demethylated metabolite norfluoxetine, which has comparable pharmacological activity. In the past few years, our research group has developed sensitive methods based on HPLC with fluorimetric detection for the therapeutic drug monitoring of fluoxetine and norfluoxetine in human plasma. Recently, however, we have been required to determine very high fluoxetine levels in patients who took an overdose of the drug and we have found that the previously developed methods are unsuitable. For this reason, an alternative, rapid and feasible HPLC procedure with diode array detection (DAD) has been developed. The mobile phase is composed of an acetonitrile / aqueous tetramethyl-ammonium perchlorate mixture, while the stationary phase is a C8 reversed phase column; quantitation of the analyte peaks is carried out at 230 nm. The application of the method to plasma samples requires a sample pre-treatment step, which is carried out by means of solid-phase extraction, loading 250 µL of plasma on Oasis HLB cartridges and eluting the analytes with methanol. This procedure gives satisfactory extraction yield values, as well as good sample purification from matrix interference. The method seems to be suitable for the analysis of fluoxetine and its metabolite in human plasma for toxicological purposes.

La sertralina, (1S,4S)-4-(3,4-diclorofenil)1,2,3,4-tetraidro-1-naftil(metil)ammina, è un derivato della naftalenammina con predominante attività farmacologica inibitoria del reuptake presinaptico della serotonina. La sertralina è indicata per il trattamento della depressione maggiore, attacchi di panico, disturbi ossessivo compulsivi e stress post traumatico. Questo farmaco è somministrato per os in dosi giornaliere comprese tra 50 e 200 mg e poiché viene assorbito lentamente, un'unica somministrazione giornaliera è terapeuticamente efficace. La sertralina subisce un intenso metabolismo di primo passaggio ad opera del CYP450, è bio-trasformata in desmetil-sertralina, un metabolita debolmente attivo che si accumula in alte concentrazioni nel plasma allo "steady state". I livelli plasmatici terapeutici della sertralina sono compresi tra 2.8 e 112 ng/mL, sebbene con pronunciata variabilità interindividuale. Il farmaco non è esente da effetti collaterali, come ad esempio perdita dell’appetito, nausea, insonnia, che sono dose-correlati. Nel presente lavoro viene descritto un rapido e preciso metodo HPLC per la determinazione di sertralina e desmetil-sertralina in plasma umano. La separazione della sertralina e della desmetil sertralina è stata ottenuta utilizzando come fase stazionaria una colonna a fase inversa C8 e come fase mobile una miscela di tetrametilammonio perclorato e acetonitrile (50/50, v/v). La rivelazione spettrofotometrica degli analiti è stata effettuata a 230 nm. Un selettiva ed efficiente purificazione dei campioni plasmatici dalla matrice biologica è stata sviluppata per mezzo di una procedura estrattiva in fase solida che consente di concentrare il campione migliorando la sensibilità del metodo. La procedura analitica sviluppata è stata applicata all'analisi di sertralina in plasma di pazienti depressi in terapia farmacologica con Zoloft® 50 mg. Il metodo proposto sembra promettente per il TDM (Therapeutic Drug Monitoring) della sertralina come strumento per una giusta personalizzazione della terapia e attenta valutazione della compliance del farmaco e delle interazioni farmacologiche in pazienti in terapia con sertralina.

Mirtazapine (1,2,3,4,10,14b-hexahydro-2-methyl-pyrazino[2,1-a]-pyrido[2,3-c][2-benzazepine]), is the first noradrenergic and specific serotonergic antidepressant ('NaSSA'), that was approved by the Food and Drug Administration for the treatment of depression in June 1997. It is administered clinically as Remeron®, a 50:50 mixture of S(+) and R(-) enantiomers, that is supplied for oral administration as scored film-coated tablets containing 15 or 30 mg of mirtazapine. It has two major metabolites, N-demethylmirtazapine and 8-hydroxymirtazapine. The parent compound demonstrates the major pharmacological activity. Some minor activity is shown by the demethyl metabolite while the hydroxy metabolite is not pharmacologically active. The receptor binding affinities of the enantiomers of mirtazapine are different, the (+) enantiomer being the more potent adrenoceptor antagonist of the two. For this reason a chiral separation of the enantiomers may be important in pharmacokinetic studies and for evaluating the clinical response. Aim of this study is the development of a capillary electrophoretic method for the enantioseparation of mirtazapine and its active metabolite. For method optimisation several parameters were investigated, such as cyclodextrin and buffer concentration, buffer pH and capillary temperature. Baseline enantioseparation of the racemic compounds was achieved in 2.5 minutes using a fused silica capillary (50 μm I.D. and 48.5, 40.0 cm, total and effective length, respectively), filled with a background electrolyte consisting of a 50 mM phosphate buffer at pH 2.5 supplemented with 0.3% (w/v) carboxymethyl-beta-cyclodextrin sulfate at 12.5°C and applying a voltage of 20 kV. UV detection was set at 205 nm. The implemented fast CZE stereoselective separation of mirtazapine has been applied for the determination of the enantiomeric purity of preparats containing racemic mirtazapine. The extraction of mirtazapine from the tablets consisted of a simple one-step dissolution with methanol, centrifugation and dilution. The electrophoretic procedure demonstrated to be very rapid and feasible and seems to be suitable for quality control of mirtazapine tablets. Experiments are in progress in order to apply the method to the determination of mirtazapine and its active metabolite in biological fluids.

of the bone around the implants was observed. Conclusion Titanium needle impla­ nts can be used with immediate load­ ing in the posterior atrophic sector, especially in the elderly people, in the zone below the maxillary sinus, in the upper front area. They also give stability to other implants. In all cases, intra­oral welding is necessary and requires specific clinical train­ ing. Needle implants are not suitable for deep and wide ridges containing dense spongy bone.

β-cyclodextrin derivatives, namely 6A methylamino-β-CD and hepta-methylamino-β-CD have been used as chiral selectors for the enantiomeric separation of a number of acidic and basic compounds by capillary electrophoresis employing either coated or uncoated capillaries. The effects of the CD type and concentration and the pH of the background electrolyte on the mobility and chiral resolution of the analytes have been studied. The use of monomethylamino-β-CD in a coated capillary allowed the enantiomeric resolution of phenyl lactic acid, warfarin and acenocoumarol but was not successful for tiaprofen and its 3-isomer. The heptamethylamino derivative, under the same experimental conditions, was a better chiral selector than the monosubstuted CD toward the arylpropionic acids and phenyl lactic acid while the anticoagulant drugs showed poor or no chiral resolution. Inversion of migration order was obtained for phenyl lactic acid, warfarin and acenocoumarol enantiomers. The enantiomers of basic compounds of pharmaceutical interest, namely propranolol, terbutaline, ketamine, chlorpheriramine and isoproterenol were only resolved using monomethylamino-β-CD dissolved in a phosphate buffer containing tetramethylammonium ions.

This paper reports the use of novel phenyl-hexyl core-shell particles packed into fused silica capillaries in nano-LC. Capillary columns of different id of 25, 50, 75, 100, and 150 mwere packed employing the slurry packingmethod. The columns were used for the separation of a model mixture containing five aromatic hydrocarbons. Benzene, toluene, ethylbenzene, n-propylbenzene, and n-butylbenzene were separated utilizing an isocratic elution mode. Mixtures of water/ACN at different ratio were studied to find optimal experimental conditions for baseline separation of all sample components. As expected with this novel stationary phase, an RP chromatographic mechanism was observed. A mixture of water/ACN, 30:70, v/v allowed the complete resolution of the studied analytes. Efficiency increased by decreasing the capillary id recording the highest number of plates per meter with capillaries of 25 m id. The decrease of the column id also resulted in a flatter dependence of the plate numbers on the linear flow rate of the mobile phase allowing the increase of the flow rate of the mobile phase without significant decrease of efficiency.

The separation of enantiomers of ten chiral arylpropionic acid derivatives was studied on six different polysaccharide-based chiral HPLC columns with various normal-phase eluents. Along with the successful separation of analyte enantiomers, the emphasis of this study was on the effect of the chiral selector and mobile phase composition as well as of the separation temperature on the elution order of enantiomers. The interesting phenomena of reversal of enantiomer elution order function of the polysaccharide backbone (cellulose or amylose), type of derivative (carbamate or benzoate), nature and position of the substituent(s) in the phenylcarbamate moiety, the polar modifier of the mobile phase (ethanol or 2- propanol), its content in the mobile phase, and separation temperature were investigated. In addition, an unusual increase in retention with increasing temperature was observed for some arylpropionic acid derivatives.

Enantiomers represent a class of compounds extensively investigated since they can show totally different behaviors when they interact with a chiral environment. Because of their identical chemical structure (they differ only in the spatial arrangement of the atoms in the molecule), the separation of optical isomers is a challenging task of analytical chemistry. So far employed methods for the separation of enantiomers are mainly based on chromatography. CE as well was considered as an analytical technique suitable for chiral separations, characterized by high efficiency and low consumption of reagent. Recently, miniaturization was introduced in LC to answer the needs to perform analyses in the minimum time, to use the smallest amount of samples and to reduce environmental pollution. Nano-LC represents nowadays a valid alternative to the abovementioned conventional analytical techniques, and can be advantageously exploited for enantiomeric separation especially because it needs minute amounts of the chiral material necessary to carry out enantiomeric separations. This review describes the development and applications of nano-LC in the field of chiral separations. The data reported in literature show its relevance for the study enantiomers-chiral selectors interaction, as well as for application in pharmaceutical and clinical research. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

Titanium (Ti) is the most widely used material in implantology for dental, orthopedic and maxillofacial purposes due to their excellent biocompatibility and mechanical properties Several data suggest that implant anchorage to bone and soft tissue can be modulated by surface characteristics. Fibroblasts are the soft tissues cells concerned in producing extracellular matrix and collagen. The aim of this work is to compare five different titanium surface treatments in order to investigate which one had the best behavior using Human Fibroblast (HFb) after seven days in culture medium. The expression levels of some adhesion and traction-resistance related genes (COL11A1, COL2A1, COL9A1, DSP, ELN, HAS1, and TFRC) were analyzed using real time Reverse Transcription-Polymerase Chain Reaction (real time RT-PCR). Titanium disks can lead to implant integration promoting the production of protein involved in cell-cell and cell-matrix adhesion and in stress-resistance, required for a good outcome in dental implantology

A chiral continuous bed was realized by a simple one-step synthesis and used to perform enantioseparations of drugs in nano-liquid chromatography (nano-LC). The capillary format of columns of this miniaturized technique allows to easily prepare in situ the chromatographic media. The continuous bed (also called monolithic) column was synthesized employing water-soluble comonomers and hydroxypropyl-? -cyclodextrin (HP-?-CD) was selected as chiral selector. In order to make possible the one-step synthesis, HP-?-CD was previously activated as the allyl derivative. Several polymeric mixtures were studied to increase the enantiorecognition capability of the column. Analyses were carried out employing aqueous mobile phases, and the effect of organic modifiers and pH on enantiomeric resolution were studied. Among tested compounds, nomifensine and naproxen were baseline resolved, using a mobile phase containing respectively 20/80 methanol/water and 20/80 acetonitrile/water, both buffered with 0.1% triethylamine-acetate. A partial resolution was achieved also for praziquantel, metomidate and 5-methyl-5-phenyl-hydantoin.

Narrow diameter implants (NDI) (i.e. diameter 3.75 mm) are a potential solution for specific clinical situations such as reduced interradicuiar bone, thin alveolar crest and replacement of teeth with small cervical diameter. NDI have been available in clinical practice since the nineties but only a few studies have analyzed their clinical outcome. Since no report is available on a new type of implants, a retrospective study was performed. A total of 47 narrow diameter (i.e. x ≤ 3.40 mm) two-piece implants (FMD srl, Rome, Italy) were inserted, 35 in females and 12 in males. The median age was 60 ± 11 (min-max 30–80 years). Implants were inserted 22 in the maxilla and 25 in the mandible; they replaced 11 incisors, 3 cuspids, 21 premolars and 12 molars. Implant' length was shorter than 10 mm, 10.30 ≤ x ≤ 12.30, equal to 13 mm and longer than 13 mm in 17,28,1 and 1 fixtures, respectively. Implant' diameter was narrower than 3.5 mm. There were 3,18 and 26 Elisir, I-fix and Shiner implant types. No implant on single tooth rehabilitations was lost and thus survival rate was 100%. Then peri-implant bone resorption (i.e. delta IAJ) was used to investigate SCR. Seven fixtures have a crestal bone resorption greater than 1.5 mm (SCR = 85.1). Statistical analysis demonstrated that diabetes (p=0.044) and smoke (p=0.001) have a higher peri-implant crestal bone resorption. In conclusion FMD implants are reliable devices for oral rehabilitation with a very high SCR and SVR although smoker and diabetic patients have a worse clinical outcome.

Implant prostheses are often used to restore partially or completely edentulous patients but limited bone height, especially in the posterior mandible, may restrict the use of dental implants. Short implants (i.e. x ≤ 10 mm) may be selected in these situations. They have several advantages: 1 - restricting the need for sophisticated and expensive surgical procedures like sinus lifting, bone grafting and mandibular nerve transposition, 2 - placing short-span dentures and 3 - avoiding cantilevers in the posterior sextants. The limited surface area of SIs, conversely, can be a potential disadvantage as it has less resistance to occlusal forces. Since no report is available on a new type of implants, a retrospective study was performed. A total of 148 short (i.e x ≤ 10 mm) two-piece implants (FMD srl, Rome, Italy) were inserted, 91 in female and 57 in males. The median age was 58 ± 12 (min-max 25–80 years). Implants were inserted 68 in the maxilla and 80 in the mandible. One implant was lost, survival rate = 98.52%. Among the studies variables post-extractive implants on single tooth rehabilitations (p=0.043) was the only significant variable. Then peri-implant bone resorption (i.e. delta IAJ) was used to investigate SCR. Among the remaining 147 implants, 18 fixtures have a crestal bone resorption greater than 1.5 mm (SCR = 87.75). Statistical analysis demonstrated that only diabetes has a negative impact on peri-implant crestal bone resorption (p=0.016). In conclusion FMD implants are reliable devices for oral rehabilitation with a very high SCR and SVR.

In the last two decades, several investigators have reported immediate placement of dental implants into extraction sockets achieving excellent results with a two-stage surgical procedure. Recently immediate loading has become an emerging technique as it has been documented to be a successful and time saving procedure. As regard the possibility of immediate/early loading of implants placed in fresh extraction sockets few reports are available. In addition they are based on limited series with short follow-up. Thus we decided to perform a retrospective study on a series of post-extractive implants. A total of 40 two-piece implants (FMD srl, Rome, Italy) were inserted in post extractive sockets, 22 in females and 18 in males. The median age was 52 ± 11 (min-max 24–69 years). Twenty-one implants were inserted in upper jaw and 19 in mandible. Fixtures replaced 7 incisors, 3 cuspids, 12 premolars and 18 molars. Implant' length was x ≤ 10 mm, 10,30 ≤ x ≤ 12.30, equal to 13 mm and x ≥14 mm in 6,14,9, and 11 cases, respectively. Implant' diameter was narrower than 3.5 mm, equal to 3.8 mm and wider than 4.0 mm in 1,7, and 32 cases, respectively. There were 28, 2 and 10 Elisir, I-fix, and Shiner implant types, respectively. No implant on single tooth rehabilitations, was lost, survival rate = 100%. Then peri-implant bone resorption (i.e. delta IAJ) was used to investigate SCR. Seven fixtures have a crestal bone resorption greater than 1.5 mm (SCR = 82.5%). Statistical analysis demonstrated that there was a difference between surgeons (p= 0.005). In conclusion FMD implants are reliable devices for oral rehabilitation with a very high SCR and SVR.

Aloe emodin is an anthraquinone compound found in Aloe vera and other species of the Asphodelaceae and the Polygonaceae families, which has recently attracted much attention as a prospective antineoplastic agent. A HPLC method with tandem UV absorption and fluorimetric detection, was developed and validated for the analysis of aloe emodin in products obtained from Aloe leaves, such as capsules, tablets, dried extracts and mother tinctures. The stationary phase was a C18 reversed-phase column and the mobile phase was composed of water and methanol (30/70, v/v). Satisfactory linearity was obtained over the 10.0-1000.0 ng/mL range for photodiode array detection (limit of detection: 3 ng/mL) and over the 2.5-1000.0 ng/mL range for fluorimetric detection (limit of detection: 0.8 ng/mL). Aloe emodin levels were determined in A. vera extracts and commercial formulations by both detection means, with good precision (R.S.D. < 9%) and accuracy (recovery > 85%) and consistent results. Thus, the method seems to be suitable for the analysis of aloe emodin in different herbal and commercial products; it could also be useful for the identity confirmation of formulations and extracts.

A large number of oral cancer patients shows poor or partial response to chemotherapy and the mechanisms are poorly understood. Glutathione-S-transferase (GST) is one of the molecules involved in resistance to natural product-based chemotherapeutics. It is an enzyme able to conjugate several substances (metabolites, drugs) to reduct glutathione. Today several isoenzymes of GST are known: GST-alpha, GST-mu, GST-pi, GST-theta. Over-expression of glutathione S-transferase-pi class isozyme is often associated with malignant transformation. Several studies reported that GST-pi staining patterns and their distribution may be helpful in identifying high-risk oral lesions. However, GST is surely involved in resistance to alchilant agents.To verify the possibility of implication of GST in oral cancerogenesis and in natural chemioresistance, the authors examined the protein expression patterns by immunohistochemistry in paraffin-embedded specimens of primary untreated oral cancers (OSCC).GST-a and GST-pi expression in 17 cases of OSCC at different degree of cellular differentiation have been evaluated by immunohistochemistry.The GST-pi expression in primary tumours predominantly varied from mild to moderate levels. The GST-a expression was often quite similar to GST-pi expression with a few exceptions.Expression of GST enzymes is an important signal for multidrug resistance: positive staining for both GST-pi and GST-a could constitute a hallmark of chemoresistant groups of OSSC.

The S-(-)-enantiomer of ofloxacin, a chiral fluoroquinolone antibiotic, exhibits an antibacterial activity 8-128 times higher than that of the R-(+)-isomer. A new stereospecific nano-LC method for the enantioseparation of the ofloxacin racemic mixture was developed using an achiral reversed phase column (Pinnacle II Phenyl 3 ¼m, 15 cm x 100 ¼m ID) and heptakis-(2,3-diacetyl-6-sulfo)-beta-cyclodextrin (HDAS-beta-CD) as a mobile phase chiral additive. Best enantioresolution was achieved using a mobile phase containing acetonitrile, 50 mM sodium acetate buffer pH 3 (30:70, v/v) and 5 mM of HDAS-beta-CD. The flow rate thorough the capillary column was estimated in 620 nL/min and the wavelength for the UV detection was set at 290 nm. Good separation of the enantiomers was obtained is less than 10 min with a resolution and selectivity factor of 1.66 and 1.88, respectively. The effect of several experimental parameters on the chiral separation was also evaluated and the method was successfully validated in terms of linearity, accuracy and precision, showing the enantiorecognition capability of the employed sulfated beta-CD toward the ofloxacin chiral drug.