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Aceria fraxiniflora (Felt, 1906) is reported from Europe for the first time. This mite has never been described before and we therefore describe and illustrate the female and the nymph. The species was collected from the galled inflorescences and fruits of the introduced species Fraxinus pennsylvanica Marshall (Oleaceae) in Hungary, and from Fraxinus americana L. in Indiana, USA.

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CONTEXT: An in situ gelling liquid suppository is liquid at room temperature but forms a gel at body temperature. In our work, Metolose® SM-4000 (methylcellulose) is studied that basically shows thermal gelation at 68°C (2%, w/w). OBJECTIVE: The objective was to study the potency of different factors (concentration, pH, additives) to change the value of thermal gelation temperature (T (t)) for Metolose® to form an in situ gelling liquid suppository. MATERIALS AND METHODS: We studied the effect of Metolose® concentration, pH, and salts (sodium chloride, potassium chloride, sodium hydrogen carbonate, and sodium monohydrogen phosphate) on T (t) by viscosimetry. To choose the appropriate compound, in vitro drug release was examined. Rectal safety test was performed on rats in vivo after 12-hour application. RESULTS: Increasing the Metolose® concentrations (0.5-4%, w/w), T (t) can be decreased, but it also altered the consistency of gel. pH does not affect the T (t). The water-soluble salts allowed reducing the gelation temperature to 37°C. Sodium monohydrogen phosphate in 4.5% concentration was found to be the most appropriate. The impact of examined factors on in vitro drug release of piroxicam from the in situ-formed gel was characterized according to Fickian diffusion. Metolose® and the chosen salt did not cause any morphological damage on the rectal tissues. DISCUSSION: According to our study, Metolose® has the physical and chemical potential to be used as base for liquid suppositories.

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The aim of this study was the formulation and examination of a novel thermoresponsive and bioadhesive, in situ gelling drug delivery system, which can be used in the treatment of oesophageal pain and inflammation. A bioadhesive cellulose derivative (Metolose) 60SH) was used as a thermoresponsive material, because Metolose has thermal gelation properties at certain temperature. The thermal gelation temperature (T(2)) of Metolose 60SH 2 w/w% solution is above body temperature (65-66 degrees C), but by using different methods (Metolose 60SH concentration, auxiliary materials), it can be shifted near to body temperature. The pH alteration between pH=2-10 and the application of different alcohols did not influence the gelation temperature, but using water-soluble salts and changing the concentration of Metolose 60SH solution between 2 and 3 w/w% the thermal gelation point could be decreased. Different NSAIDs were used as model drugs and which had not influence on thermal gelation temperature, but difference in in vitro liberation and penetration can be observed. In vitro adhesion test pointed out that the condition of investigated membrane can change the adhesion. Morphological test of oesophageal tissue showed that investigated materials had no irritative or tissue-damaging effect on the oesophageal mucosa even after 12h.

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The purpose of the present study was to formulate a novel thermoresponsive membrane controlled therapeutic system from Metolose for possible transdermal application. Metolose gel shows thermal gelation property, which can be characterized by two (T(1), T(2)) temperatures. A sharp decrease of viscosity can be measured at T(1), but gelation can be observed at T(2). Different types of Metolose polymers were compared considering their thermoresponsive behaviour. Only thermal gelation was observed in the case of Metolose SM, while Metolose SH showed a sudden decrease of viscosity at T(1). Since this temperature is above the body temperature, so it should be shifted to the skin temperature in case of possible transdermal application. Modulation of thermoresponsibility was followed by rheological method, and the thermoresponsive drug release from Metolose gel was studied by static liberation test. Our results demonstrated that the effect of different salts (NaCl, NaHCO(3), KCl) of various concentrations in Metolose SH gel reduced T(1) to the skin temperature, which enabled enhanced drug release.

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Transdermal therapeutic systems (TTSs) were studied applying different sucrose fatty acid esters (SEs) as drug delivery agents. Matrix and membrane controlled TTSs were prepared and compared. Membrane was made from a methacrylic polymer (Eudragit NE) of pH independent permeability which can achieve diffusion controlled drug liberation. Model drug was a water soluble beta-blocker, metoprolol, which has short biological half-life, so applying it in a TTS, the duration of its action could be prolonged. Sucrose fatty acid esters of different fatty acid chain lengths and consequently different hydrophilic-lipophilic balance (HLB) values were studied considering their effect on the metoprolol release from TTSs. Different mathematical models were applied for the evaluation of the release process. The results of the in vitro studies indicated that SEs of shorter fatty acid chain length and higher HLB value increased the amount of released drug about 10 times. SEs could be promising agents in transdermal therapeutic systems to control the drug release and cutaneous absorption.

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The Marble gallwasp Andricus kollari has a native range divided into two geographically separated lifecycles. In Eastern Europe and Turkey, the lifecycle involves a sexual generation on Turkey oak, Quercus cerris, while in Iberia and North Africa the sexual generation host is cork oak, Q. suber. Over the last 500 years, A. kollari has expanded its range into northern Europe, following human planting of Q. cerris from Italy and the Balkans. We ask: (i) what is the genetic relationship between eastern and western distributions of Andricus kollari? Can we determine which lifecycle is ancestral, and how long ago they diverged? (ii) To what extent have eastern and western native ranges contributed to northwards range expansion? (iii) Is there any evidence for hybridization between the two life cycle types? We present analyses of allozyme data for 13 polymorphic loci and of sequence variation for a 433 bp fragment of the mitochondrial cytochrome b gene. These show: (i) that four haplotype lineages (one in Spain, two in Hungary/Italy and one in Turkey) diverged more or less simultaneously between 1 and 2 million years ago, suggesting the existence of at least four refuges through recent ice age cycles. Our data cannot resolve which lifecycle type is ancestral. (ii) Populations north of putative refuges are divided into two sets. Populations in south-west France are allied to Spain, while all remaining populations in northern Europe have been colonized from Italy and the Balkans. (iii) The transition from one race to another in south-west France is marked by abrupt transitions in the frequency of refuge-specific private alleles and corresponds closely to the northern limit of the distribution of cork oak. Although hybrids were detected in north-west France, none were detected where the two lifecycles meet in south-western France. The biology of oak gallwasps predicts that any hybrid zone will be narrow, and limited to regions where Q. cerris and Q. suber meet. Our data suggest that eastern and western A. kollari are effectively separate species.

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The stability of atenolol solutions was evaluated under accelerated isothermal degradation conditions at 90 degrees C. A specific and sensitive HPLC method was adapted to study the pH dependence of the stability. The maximum stability of atenolol was achieved at pH 4 with a k value of 1.1 x 10(-3) h-1. The degradation of atenolol followed first-order kinetics at above mentioned conditions.

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The influence of different solvents (propylene glycol, glycerol, ethanol), as well as different technological procedures (melting, rapid and slow cooling), on the formation of polymorphous piroxicam modifications was examined in the course of the elaboration of a "soft-patch" type of semisolid pharmaceutical dosage form. The thermodynamical behavior, some physicochemical properties (such as melting point, dissolution rate), and infrared (IR) spectrum of the formed (needle and cubic) crystal modifications were studied, and the possibilities of their formation and their avoidance were examined.

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Field surveys of cynipid gall-inducer occurrences on Quercus species were conducted in Florida, North Carolina, and Pennsylvania, USA. All cynipids demonstrated strong host species and organ fidelity. One result of this specialization is effective niche partitioning among cynipids. The host-association patterns of these specialist herbivores should reflect similarities among oaks, thus we clustered oak species according to their cynipid distributions. Cynipids distinguished small differences among their hosts. A dendrogram of oak species based on cynipid distributions was largely congruent with botanical arrangernents. Cynipid occurrences offer information helpful to resolving some aspects of oak systematics. Collaborative efforts between taxonomic botanists and entomologists will be useful in resolving a variety of plant and insect systematic problems.

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The stability of atenolol solutions was evaluated under accelerated isothermal degradation conditions at 90 degrees C. A specific and sensitive HPLC method was adopted to study the pH dependence of the stability. The maximum stability of atenolol was achieved at pH 4. The degradation of atenolol followed first-order kinetics at 90 degrees C, pH 4 with k value of 1.1.10(-3) hour-1.

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Authors call attention on the possibilities that drug release from solid preparations can be influenced by solubility and dissolution rate according to the clinical requirements regarding the duration of action. The therapeutic time interval may be modulated influencing the rate of absorption by controlling dissolution rate and changing the transport through the membranes. The results obtained from dissolution, absorption and efficacy studies of the evaluated active substances (magnesium oxide, metoprolol, nitrofurantoin) demonstrate the significance of mass transfer processes in the drug formulation.

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