Synthesis and oligomerization of cysteinyl nucleosides.

Nucleoside and nucleic acid analogues are known to possess a considerable therapeutic potential. In this work, by coupling cysteine to nucleosides, we successfully synthesized compounds that may not only have interesting biological properties in their monomeric form, but can be used beyond that, for oligomerization, in order to produce new types of synthetic nucleic acids. We elaborated different strategies for the synthesis of cysteinyl nucleosides as monomers of cysteinyl nucleic acids using nucleophilic substitution or thiol-ene coupling as a synthetic tool, and utilised on two complementary nucleosides, uridine and adenosine. Dipeptidyl dinucleosides and pentameric cysteinyl uridine were prepared from the monomeric building blocks, which are the first members of a new class of peptide nucleic acids containing the entire ribofuranosyl nucleoside units bound to the peptide backbone.

MicroRNAs: Suggested role in pituitary adenoma pathogenesis.

MicroRNAs (miRNAs) are small non-coding RNA molecules that represent a major class of molecular regulators. miRNAs have been implicated in the pathogenesis of several human tumors, including pituitary adenomas. Altered expression of miRNAs has been described in pituitary adenomas, and specific miRNA signatures are related to clinical and therapeutic characteristics of the tumors. The data suggest that miRNAs influence various genes known to be associated with the pathogenesis of pituitary adenomas and in this review we summarize these currently available studies focusing on miRNAs in pituitary adenomas.

Inhibitory effect of ragweed (Ambrosia artemisiifolia L)-inflorescence extract on the germination of Amaranthus hypochondriacus L and growth of two soil algae.

In this study the ecological importance of common ragweed (Ambrosia artemisiifolia L.; Asteraceae) was investigated in in vitro bioassays as it is one of the most widespread annual weeds occurring on arable land in Hungary. Eight fractions were derived from ragweed inflorescence water extract by low vacuum column chromatography and their biological activity was investigated by Amaranthus hypochondriacus L. cv. Edit (Amaranthaceae) germination bioassay. As a result of the germination bioassay the chromatographic method was modified to harvest the most effective fractions in only one fraction, which was used in three concentration (10, 50, 100 mg x kg(-1)) for algal growth inhibition bioassay. Results showed significant growth inhibition in case of both applied algal species.

Different action patterns for apple pectin methylesterase at pH 7.0 and 4.5.

The mechanism of action of purified apple pectin methylesterase on pectin (degree of methoxylation: DM 75) and methoxylated homogalacturonans (DM 70 and 90) was studied at pH 7.0 (optimal pH of the enzyme) and at pH 4.5 (close to the pH of apple juice). Different interchain distributions of the free carboxyl groups were obtained at pH 7.0 and 4.5: high-performance ion exchange chromatography indicated a typical single chain mechanism at pH 7.0, but a mechanism differing from the single and multiple chain ones at pH 4.5. However, the same intrachain distribution of the newly demethoxylated galacturonic acid residues was observed for both pHs by 1H NMR. The high content of consecutive de-esterified or consecutive esterified galacturonic acid residues suggested that apple PME acted with a multiple attack mechanism on the pectic substrate. The degree of multiple attack of the enzyme was greater than or equal to 10-11.

[The development and action-mechanism of the quadhelix in orthodontic treatment]. / A quadhelix kialakulása és hatásmechanizmusa a fogszabályozó kezelésben.

Authors present a historical review of the development of quadhelix appliance. In conclusion, slow maxillary expansion with the quadhelix appliance provides an alternative approach to rapid maxillary expansion that is particularly beneficial for correction of transverse and arch-length discrepancies during the mixed dentition. There are numerous indications for this approach with two major advantages. First, a lower force that is within the elastic limits of maxillary sutural and periodontal tissue is generated. Second, a low separation rate of 0.4-1.1 mm per week allows for more physiologic adaptation to the expansion that may result in a more stable correction with less sutural relapse. The quadhelix is a versatile appliance that provides practitioners a convenient means to normalize developing malocclusions.

[Psychosomatic correlations in orthodontics--the impact of dentition anomalies on the mental status]. / Pszichoszomatikus összefüggések az orthodontiában--a fogazati rendellenességek kihatása a lelki alkatra.

Authors present the essence of psychosomatics with particular emphasis on the impact of dento-occlusal and cranio-facial anomalies on the mental constitution. In their representation--after giving a historical review--they show the main features of the present state of knowledge in this branch of science based on literary publications by completing it with their own clinical experience.

An exact representation for the generating function for the Moolgavkar-Venzon-Knudson two-stage model of carcinogenesis with stochastic stem cell growth.

The two-stage clonal expansion model of carcinogenesis provides a convenient biologically based framework for the quantitative description of carcinogenesis data. Under this stochastic model, a cancer cell arises following the occurrence of two critical mutations in a normal stem cell. Both normal cells and initiated cells that have sustained the first mutation undergo birth-and-death processes responsible for tissue growth. In this article, a new expression for the probability generating function (pgf) for the two-stage model of carcinogenesis is derived. This characterization is obtained by solving a partial differential equation (pde) satisfied by the pgf derived from the corresponding Kolmogorov forward equation. This pde can be reduced to the hypergeometric differential equation of Gauss, which leads to a closed-form expression for the pgf requiring only the evaluation of hypergeometric functions. This result facilitates computation of the exact hazard function for the two-stage model. Several approximations that are simpler to compute are also given. Numerical examples are provided to illustrate the accuracy of these approximations.

[Esthetic and social indications for the "redressement forcé" technic and the hazards of this surgical procedure]. / A "redressement forcé" esztétikai, szociális indikációja és a mütét kockázata.

The authors report on-, and evaluate the type of operation known as "redressement force" for the correction of retained upper canines. The risk of the surgical intervention is extremely high, but there are good reasons for the indications, too.

[Surgical-orthodontic correction of unerupted upper canine teeth and motivation for the procedure from the patient's viewpoint]. / Retineált felsö szemfogak sebészi-orthodontiai korrekciója és a kezelés motivációja a páciens részéröl.

The surgical correction of the retention of upper canines is made easier by the direct bonding method, furthermore it increases the chances of successful treatment. At the same time at teen-age the treatment is usually missing, since the persistent milk-teeth in the place of impacted canines are ensuring the aesthetic effect. The late treatment is motivated by aesthetic aspects also by loosing the milk-canines. Thus the indication of the treatment is a cure only from the orthodontist's aspect, from the patient's view it's only the aesthetics.

[Burstone's segmented arch technic]. / A Burstone-féle szegmentívtechnika.

The authors have introduced the segmented arch technique of Burstone on the base of the literature and of own experiences. They are reporting about the theory and the advantages of the technique and its adaptability in the daily orthodontic practice.

[Effect of various mouthwashes on wound healing after tooth extraction]. / Különbözö gyógyszeres öblítö szerek hatása az extractiós seb gyógyulására.

The results of the clinical tests involving 200 patients show that after extraction the use of Meridol, NaF and Chlorhexidine mouthrinses along with careful mouth hygiene helps healing to a great extent. The antiseptic affect of solutions in case of solutions of fluoride content are manifested in an antibacterial way, while solutions of chlorhexidine content act in an antiseptic way. Furthermore the solutions foster good oral hygiene and in this way lessen the number of complications. This is shown by the decreased frequency rate of gingivitis and also the opinions of the patients. Their reports confirm that there is less foetor ox ore, pain and functional insufficiency in mastication. Based on these facts we can state that any of the three mouthrinses considerably helps complication-free healing.

[Clinical experience with the use of ceramic orthodontic brackets]. / Klinikai tapasztalatok porcelán orthodontiai zárakkal.

The advantage and disadvantage of applying ceramic orthodontic brackets were compared on base of practical experiences. The application of ceramic brackets is recommended in the clinical practice, considering that also enamel injuries may develop by debonding.

[Indications for preventive removal of impacted third molars]. / Az impactált bölcsességfogak preventív eltávolításának indikációi.

The impacted third molars are clinically important due to the pathological alterations caused by them. It is important from orthodontic viewpoint, that during their development the anomalies combined with the constriction, or unsuitable length of the dental arch may lead to recrudescence. For this reason the preventive removal of impacted third molars is suitable at the proper stade of their development.

[Orthodontic treatment as prevention of periodontal changes]. / Fogszabályozó kezelés mint a parodontalis elváltozás prevenciója.

Even the general dental practitioners consider the orthodontic therapeutical interventions carried out with removable appliances as a harmful procedure. It is much less known how the lack of adequate orthodontic treatment endangers the peridontium. Clinical data show a cause related correlation between the maxillary incisor protrusion, mandibular frontal jammed dentition, deep vertical overbite, openbite, crossbite early deciduous tooth extractions and the periodontal pathological happenings. So it is very important to start an early orthodontic treatment to avoid the periodontal consequences of malocclusion before it has become irreversible.

Results of a 3-year oral hygiene programme, including amine fluoride products, in patients treated with fixed orthodontic appliances.

This paper reports the results of a 3-year study on children treated with fixed orthodontic appliances. They were all regularly instructed in oral hygiene maintenance and used a standardized fluoride-free toothpaste during the course of the study. The patients were divided into three groups. Groups one and two, respectively, had a fluoride gel and fluoride fluid (Elmex amine fluoride products, GABA International Ltd, Basle, Switzerland) applied. Group three used only the toothpaste supplied, had oral hygiene instruction, but not topical applications. Caries increments were lowest and gingival health best in the two groups using amine fluorides, especially the gel group.

General anaesthesia of out-patients in pedodontics.

Complete dental treatment of 180 children has been undertaken under general anaesthesia. Indications for this were mental retardation and dental fear. Because of the simple technique and advantageous pharmacological properties, ketamine, and later its Hungarian analogue, Calypsol, were used.

[Experience with amalgams manufactured by Southern Dental Industries (Australia)]. / Tapasztalataink az SDI cég által gyártott amalgámmal.

The gamma 2 phaseless amalgam of the firm Southern Dental Industries (SDI) was tested. None of the 205 fillings showed level deviations, unevenness, secondary caries and breakage. A minimum size gap was found in 2 cases.

[The teaching of preventive directives in pediatric dentistry in the curriculum of dental education]. / A gyermekfogászati komplex megelözés oktatása a fogorvosképzésben.

The four directional (right nourishment, mouth hygiene, fluorides, early treatment) complex Infant Dentistry prevention and its teaching viewpoints are summarized. It is emphasized that no order of importance must be made among the four directions since lasting success can be achieved only by consequent carrying out of all tasks.