In vitro food-drug interaction study: Which milk component has a decreasing effect on the bioavailability of ciprofloxacin?

The purpose of the present work was developing an in vitro dissolution test to highlight the possible molecular background causing ciprofloxacin (CPFX)-milk interaction. The in vitro dissolution of CPFX from film-coated tablets (Ciprinol) 500mg) was examined at different pH values, simulating certain parts of the gastrointestinal tract, in the presence of water, low-fat milk, casein- or calcium enriched water. In order to determine the amount of dissolved CPFX, solid phase extraction sample preparation followed by high performance liquid chromatography coupled with mass spectrometry was applied. Comparing the dissolution efficiency values in various media, it can be concluded, that casein has a more pronounced effect on the absorbable amount of the antibiotic at each pH value studied, than calcium. In the case of concomitant intake of CPFX film-coated tablet and milk or other dairy products not only the complexation with calcium, but also the adsorption of CPFX on the surface of proteins decreases the absorbable amount of CPFX.

Characterization of liposomal vesicles encapsulating rhodanese for cyanide antagonism.

The major mechanism of removing cyanide from the body is its enzymatic conversion by a sulfurtransferase, e.g. rhodanese, to the less toxic thiocyanate in the presence of a sulfur donor. Earlier results demonstrated that externally administered encapsulated rhodanese significantly enhances the in vivo efficacy of the given sulfur donor. Present studies are focused on liposomal carrier systems encapsulating rhodanese. Physicochemical properties, e.g. membrane rigidity, size distribution, surface potential, osmolarity, and viscosity, were determined for various liposomal lipid compositions and hydrating buffers to establish in vitro stability and in vivo fate. Lipid composition was also optimized to achieve maximum encapsulation efficiency.

Liposomal oxytetracycline and doxycycline: studies on enhancement of encapsulation efficiency.

Liposomal encapsulations of oxytetracycline (OTC) and doxycycline (DC) with various lipid compositions and hydrating solutions have been studied in order to develop a new liposomal formulation to treat bacterial infections. Encapsulation efficiencies as a function of pH (pH 4.0-8.0) in ionic (phosphate buffers) and non-ionic (mannitol or glucose) hydrating solutions with various lipid compositions (lecithin or α-L-dipalmitoylphosphatidylcholine, with or without cholesterol) were determined and compared to the character of lipid vesicles. Based on our encapsulation efficiency studies and on the drug stability considerations it can be concluded that for OTC/DC encapsulation the use of non-ionic solutions is the most promising.

[Mills' syndrome: a rare clinical entity]. / Syndrome de Mills: une entité clinique rare.

INTRODUCTION: Mills' syndrome is a rare motor neuron disease, initially described by Mills in 1900 as a progressive ascending or descending hemiplegia without significant sensory involvement. This syndrome is of uncertain nosological status, and is supposedly due to unilateral primary degeneration of corticospinal pathway. Some authors have suggested that it could represent a variant of primary lateral sclerosis. METHODS: We retrospectively studied the clinical and paraclinical data from eight patients with suspected Mills' syndrome hospitalized for diagnosis. RESULTS: For all patients, the clinical course was slowly progressive, with motor deficiency, unilateral pyramidal signs (or bilateral with asymmetry), without bulbar signs, fasciculations or sensory deficit. Final diagnosis was Mills' syndrome (n=3), primary lateral sclerosis (n=1), myelitis of unknown origin (n=2), progressive primary multiple sclerosis (n=1), and antiphospholipid syndrome (n=1). The main arguments for final diagnosis were brought by electrophysiology and brain and spinal MRI. CONCLUSION: Mills' syndrome is a rare clinical diagnosis, requiring exhaustive investigations.

Prevalence of accessory tooth cusps in a contemporary and ancestral Hungarian population.

Dental morphological characteristics are useful for providing information for phylogenic and genetic studies and understanding variations within and among species. Carabelli and talon cusps are expressed in several degrees and different frequencies between humans, thus being useful in comparing and characterizing populations. The purpose of this study was to examine the incidence and degree of expression of a Carabelli tubercle and talon cusps in a contemporary Hungarian population compared with similar findings in the dentition of skulls dating from the 11th century, the so-called Arpád-era. The data were collected by examination of dental plaster casts of 600 children aged 7-18 years (304 males, 296 females) undergoing orthodontic treatment. The dentitions of 147 skulls, dating from the 11th century, from the ancient Halimba-Cseres cemetery stored at the Hungarian Natural History Museum were also examined. The incidence and degree of expression of a Carabelli cusp was investigated for the upper first permanent molars and scored according to an eight-grade classification system. The talon cusps on the upper permanent lateral incisors were also examined. A chi-square test was used for statistical analysis. The prevalence of Carabelli cusps was 65.34 per cent in the contemporary and 34 per cent in the 11th century population (P < 0.01). The contemporary group showed a prevalence of talon cusps of 2.5 per cent compared with 40.8 per cent for the skills from the Arpád-era, which was significant (P < 0.001). These findings demonstrate that the contemporary Hungarian population is a mixture of European and Mongoloid races. The data are in agreement with linguistic evidence that shows that distant Hungarian ancestors belonged to the Finno-Ugrian family of people, whose habitats extended from the Baltic to the middle Urals.

Studies on molecular interactions between nalidixic acid and liposomes.

The interaction between nalidixic acid sodium salt (NANa) and liposomes prepared from alpha-L-dipalmitoyl-phosphatidylcholine (DPPC) or from its binary mixture with dioleoyl-phosphatidylcholine (DOPC) was studied with differential scanning calorimetry (DSC) and electron paramagnetic resonance (EPR) spectroscopy. We evaluated the role of broadband ultraviolet-B (UV-B) irradiation on the molecular interactions between the lipids and the NANa, and determined the decay-kinetics of the incorporated spin labeled fatty-acid free radicals. Multilamellar and unilamellar vesicles were prepared by sonication and extrusion. The entrapment efficiencies were determined spectrophotometrically. The size-distribution of the liposomes and its change in time was checked by dynamic light scattering (DLS). Our results indicate that NANa mainly interacts with lipid head groups. However, its effect and presumably the formation of the free radicals, induced by broadband ultraviolet-B, is not localized only to the head group region of the lipid molecules. Depending on DOPC content, interaction between the NANa and the lipids modifies the phase-transition parameters of the liposome dispersions.

Molecular interactions between DPPC and morphine derivatives: a DSC and EPR study.

The interaction between different morphine derivatives (morphine, codeine, N-methyl-morphine, N-methyl-codeine) and alpha-L-dipalmitoyl phosphatidylcholine (DPPC) liposomes was studied with differential scanning calorimetry (DSC) and electron paramagnetic resonance (EPR) spectroscopy. Small unilamellar DPPC-liposomes with the given morphine-derivative were prepared by sonication. The size distribution of liposomes was checked by dynamic light scattering (DLS). The amount of entrapped morphine was determined spectrophotometrically. Our results indicate that the morphine and its derivatives principally interact with the lipid head groups, and this interaction leads to a decrease in the mobility of the polar head groups, especially in case of codeine and N-methyl-codeine.

[Preparations of liposomal morphine. Investigation of the interaction of morphine and its derivatives with the dipalmitoyl phosphatidylcholine membrane]. / Morfin liposzómába zárása. Morfinszármazékok dipalmitoil-foszfatidilkolin membránnal kialakuló kölcsönhatásának vizsgálata.

Liposomes composed of the lipids of biological membranes are suitable for drug delivery. To reach a better therapeutical effect it is important to know the properties of interactions between the drug and lipid molecules. From dipalmitoyl phosphatidylcholine (DPPC) using ultrasound small liposomes containing morphine were prepared. The amount of entrapped morphine was determined with spectrophotometry and luminescence spectroscopy. The interaction between the molecules of morphine and its derivates (codeine, N-methyl-morphine, N-methyl-codeine) and the DPPC lipid was studied with differential scanning calorimetry (DSC) and electron spin resonance (ESR) methods. Our studies indicated that the molecules of morphine and its derivates principally interact with the environment of DPPC lipid head groups. Due to the interaction the mobility of head groups decreases especially in case of codeine and N-methylcodeine.

[Liposomes as drug carrier systems. Preparation, classification and therapeutic advantages of liposomes]. / A liposzóma mint gyógyszerszállító rendszer. A liposzómák elóállítása, alapvetó típusaik és terápiás alkalmazásuk elónyei.

Bangham et al. (1965) created first the concept of the liposome as a microparticulate lipoidal vesicle separated from its aqueous environment by one or more lipid bilayers. Later Gregoriadis and Ryman (1972) suggested to use liposomes as drug carrier systems. Nowadays liposomes are under extensive investigation for improving the delivery of therapeutic agents, enzymes, vaccines and genetic materials. Liposomes offer an excellent opportunity to selective targeting of drugs which is expected to optimize the pharmacokinetical parameters, the pharmacological effect and to reduce the toxicity of the encapsulated drugs. To understand the system it is important to know the basic properties of these lipoidal vesicles. Our aim was to focus on the lipid composition and the method of liposome preparation what determine the liposomal membrane fluidity, permeability, vesicle size, charge density, steric hindrance and stability of the liposomes as principle factors those influence the fate of liposomes, their interactions with the blood components and other tissues after systemic administration or local use.

[Caries, gingivitis and dental abnormalities in patients with cleft lip and palate]. / Az ajak- és szájpadhasadékos betegek cariológiai, parodontológiai és orthodontiai vizsgálata.

Oral health was studied in 31 children aged 10-12 years with cleft lip and palate and compared to 31 noncleft controls matched for sex and age. We found a difference in the prevalence and activity of caries with increase in cleft lip and palate patients. The unilateral crossbite and the congenitally missing teeth were more common in cleft palate children and the supernumerary teeth were fewer. Almost all children used fluoride tablets.

[Open bite and its management]. / A nyitottharapás és kezelési lehetöségei.

Morphological and functional symptoms of various varients of the open bite are reported on. The orthodontic treatment possibilities and, then, the surgical methods applicable after termination of jaw bone development are summarized. The functional disturbances have to be considered in case of both the conservative and the surgical treatment. A patient treated with a fixed device and an operated patient are presented.

Experimental study on the effects of +Gz. Acceleration under gestational conditions. I. Ultrastructural myocardial lesions.

In the course of a complex experimental study concerning the effects of highly positive acceleration on gestation and development of the neonate, investigations were carried out of ultrastuctural myocardial lesions in the pregnant rat exposed to prolonged gravitational stress (+ 2G). The experimental animals presented various disseminated and partly irreversible myocardial lesions whose pathogeny is discussed.