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Biomedical subjects

Iu A Petrovich

Publications and source records attributed to Iu A Petrovich.

At least 19 recordsLinked to original sources
PubMed2006

[Influence of mandibular fracture upon intensity and prevailing direction of carbonate and citrate transport between blood and bones].

Using new coefficient of the difference relative radioactivity (CD(RRA)) bone/blood there was studied [(14)C]-carbonate and [3-(14)C]-citrate in 1-month and 6-months rats after right-side fracture of the mandible in prevailing direction between blood and bone. Animals were taken out from the experiment 20 min after intraperitoneal injection of [(14)C]-carbonate and [3-(14)C]-citrate on 7th day after (stage of cell-fibrous callosity), on 14th day after (stage of chondroid callosity) and on 28th day after (stage of the primary bone callosity) the experiment start. Changes after injections of marked citrate and carbonate were similar. Input % (ratio pulse/min in bone and blood serum) and RRA in 1 week increased sharply, decreased in 2 weeks and less changing in 4 weeks. After fracture CD(RRA) in traumatized mandible and non traumatized femur in rats were changing in the opposite directions that testifies to the different prevailing directions of marked substances transport between blood and bones.

Animals↗
PubMed2004

[Study of age-specific changes in labeled citrate metabolism in health and disease].

A new coefficient - mineralized tissues/biological fluids (MT/BF) - is suggested for evaluating the distribution of compounds adsorbed by MT and dissolved in BF. The relative radioactivity (RRA) was estimated for the periods of 10 min to 96 h after intraperitoneal injection of [3-(14)C]citrate to rats aged 1 and 3 months and over 1 year by dividing the percent of incorporation in MT by the percent of incorporation in BF. Changes in RRA for molar root/blood serum (R/BS) and RRA for dentin/blood serum (D/BS) are similar: low values at the beginning of experiment, an increase 1 h postinjection, a decrease 2-3 h postinjection, and another increase (65-80 times) by 96 h postinjection. A biphasic reaction with a rapid elevation and decrease after 1-2 h and a second elevation before the end of the experiment due to citrate adsorption on hydroxyapatite and influence of D and R proteins on stable hemosorption of citrate by MT was observed. The time course of RRA enamel/oral fluid was different: a decrease 1 h postinjection and an increase 2-3 h postinjection. Two weeks after crossing the inferior alveolar nerve, the R/BS RRA decreased to a lesser degree in 1-month-old rats in comparison with 3-month-old animals, which can be explained by higher efficiency of the adaptive-compensatory mechanisms in growing rats.

Age Factors↗
PubMed2004

[Effect of cariesogenic diet and age on selenium distribution between blood and mineralized tissues in rats].

The distribution of Se in the blood and teeth (in the jaw and femoral bones) was evaluated using a new coefficient of relative radioactivity (RRA), representing the ratio of (75)Se in the teeth (bones) and blood. Changes in all RRA were studied during 1-192 hours after intraperitoneal injection of [(75)Se]selenate in one-month-old rats receiving common fodder; a biphasic pattern of changes was observed, with peaks 6 and 48 h and lowering 24 and 192 h postinjection. The first peak was mainly due to Se adsorption on hydroxyapatite, the second to chemo-adsorption on it and Se binding to protein. In 3-month-old rats receiving common fodder the peak of all RRA was delayed to 12-48 h postinjection, the values decreasing by 192 h. The peak of specific activity (SA) of (75)Se protein in the bones was recorded 24 h and its decrease 192 h postinjection. In one-month-old rats receiving sucrose-casein diet during 2 months all RRA and SA after 6 and 12 h and part of RRA after 24 h were higher than in the control, that is, Se absorption by bones and teeth from the blood decreased.

Aging↗
PubMed2002

[Calcium homeostasis disorders in children with multiple caries].

A saliva of the examined children of 3, 6, 12 years old with intensive caries are characterized by a changing of calcium homeostasis which is accompanied with redistribution of calcium fractions in a mixed nonstimulation saliva. In this case the concentration of Ca2+ is raisign considerably while the concentration of general calcium is raising slightly.

Calcium↗
PubMed2002

[Pathogenetic validation of xidiphone use in combined therapy for periodontal diseases].

It is well grounded for the application of a preparation from group bisphosphonates xydiphone is justified (reasonable). For treatment and preventive maintenance of a tooth stone for want of periodontal inflammation. Is shown on 30 patients with acute parodontitis and at 10--with gingivitis (in a stage of a peaking), that the application of xydiphone will neutralize an alkaline response having a place up to treatment, due to what it(he) exhibits antiseptic of a property. Xydiphone, linking ionized Ca and free Fe, simultaneously hinders with activation of free--radical oxidation, reduces blood-flux and blocks process of crystallization.

Acute Disease↗
PubMed2001

[Integral coefficient characterizing free radical oxidation and antioxidant defense, and the new "residual" coefficient reflecting the efficiency of using antioxidants in periodontitis].

The new integral coefficient between free-radicals oxidation (FRO) and antioxidant defense (AOD) during periodontitis is offered. This "residual" index may be used for evaluation of the decrease or increase in the balance between FRO and AOD in different fluids and organs under different conditions.

Adult↗
PubMed2001

[Volatile compounds in air and oral saliva in healthy people, and in periodontitis and gingivitis patients].

21 healthy persons, 7 patients with chronic generalized periodontitis and 4 patients with chronic generalized gingivitis aged between 18 and 42 years were examined. Air from the oral cavity was collected with a special device; liquid samples were collected by washing the oral cavity with sterile water. Chemical compounds of the air and the washed liquid were analyzed by chromato-mass-spectrometry, gas-adsorption and gas-liquid chromatography. The content of dimethyl sulphide, dimethyl disulphide increased in the oral air and such volatile short chain fatty acids (VSCFA) as butyrate, propionate, acetate rose, but their aldehydes (butyraldehyde, acrolein, acetaldehyde decreased in oral fluid during periodontitis. The concentration of these compounds were found to be between the levels in control persons and during periodontitis. The content of pentane decreased in oral air. That depended on the intensity of inflammation and vessel disturbances. The results suggest that VSCFA produced by Porphyromonas, Prevotella, Fusobacterium and other periodontopathic bacteria, penetrate the oral mucosa and severely harm the periodontal tissue. The increase of dimethyl sulphide contributed to oral malodor during periodontal inflammation.

Adolescent↗
PubMed2000

[The evaluation of periodontal status by the chemical composition of the oral media].

Twelve patients aged 21-38 years with gingivitis and periodontitis and 9 subjects with intact periodontium were examined. Air from the oral cavity was collected with a special device, liquid samples were collected by gargling with sterile water. Chemical composition of the air and washings was analyzed by chromato-mass-spectrometry, gas adsorption and gas liquid chromatography. Inflammation of periodontal tissues was associated with a sharp increase in the oral air concentration of methylethylketone. The concentrations of isovaleric, n-valeric, and n-enanthic aldehydes increased appreciably. Ethanol predominated over n-butyl alcohol. The levels of dimethylsulfide and isoprene increased several times. In the washings from the oral cavity, the content of microorganism's vital activity products (fatty acids) was increased. Possible metabolic mechanisms of the detected shifts are discussed.

Adult↗
PubMed1998

[Lacrimal and salivary antioxidants in viral infection].

The activities of antioxidant enzymes in the cornea and tears in patients with ophthalmic herpes and in the saliva in those with herpetic stomatitis were assessed. Impaired inhibition of hydroxy radical and a drop of antioxidant enzymes activities and of the level of ascorbic acid in herpes-infected cornea and tears are factors in the pathogenesis of ophthalmic herpes. Measurements of enzymatic activities in the tears and saliva in herpetic infection are a valuable diagnostic test and a criterion of treatment efficacy.

Acute Disease↗
PubMed1997

[The nature of the action of chemical substances on the activity of the microflora in soft dental deposits].

Effects of the principal mineral and mineralizing components of the saliva, nutrient organic acids (carbohydrate and some others substances' metabolites) on the activity of microflora of soft dental deposit were studied in vitro. The inhibitory effect was assessed visually from the appearance or absence of deposit coating, pH measurement, and by photo- and nephelometry. Concentrations of lactic acid and sucrose were measured. The inactivating effects of the reagents were assessed by double control: qualitative, by comparing the specimen with the optic density of the extract from aqueous suspension of the deposit, and time control, by comparing the specimen with the optic density of extracts from deposit suspensions directly after mixing with the medium. Acid medium was found to block the formation of soft dental deposit and inhibit the production of lactic acid by bacterial deposit. Hence, weakly acid gargle is recommended as an effective and physiological measure preventing cariogenic situation resultant from the intake of easily fermenting carbohydrates.

Cariostatic Agents↗
PubMed1997

[Ionized calcium in the saliva of children with multiple caries].

Ionized calcium and total content of all Ca fractions were measured in mixed saliva and blood serum of children aged 4 to 12 with solitary carious lesions or multiple caries. The level of ionized Ca was much higher in multiple caries than in individual lesions, and the content of bound Ca (protein-bound and in complex with other compounds) was decreased. The authors propose that recharging of salivary proteins caused by acidification of the saliva and dental deposit due to production of lactate and other organic acids is mainly responsible for redistribution of Ca fractions in mixed saliva. Ca release which results from demineralization of teeth, changed rate of salivary secretion and permeability of the blood-saliva barrier, and other factors may also contribute to redistribution of Ca fractions in the saliva, which plays an important role in the pathogenesis of caries.

Calcium↗
PubMed1989

[The effect of the method of collecting lacrimal fluid on its composition].

The authors have examined the relationship between the technique of the tear collection and the lacrimal enzymes activity. The studies have revealed that lactate dehydrogenase (LDH) appears in the tears of normal subjects only if the tears are collected by mechanically affecting the cornea and the conjunctiva. Microinjuries of the corneal epithelium result in LDH release into the tears. If the tear is collected from the cheek after ammonium hydroxide inhalation, it contains no LDH. The activities of the lacrimal acid and alkaline phosphatases do not vary when collected by different methods. Therefore, the method for the tear collection should be taken into consideration when interpreting the results of biochemical analyses.

Humans↗
PubMed1989

[Glycosidase activity of the tears in patients with ophthalmic herpes].

The activity of three glycosidases in a tear has been studied in 26 patients with ophthalmic herpes, the diagnosis being confirmed by the method of fluorescent antibodies. The study has shown that in patients with herpetic keratitis the activity of beta-N-acetylglucosaminidase increases and that of beta-glucosidase and beta-glucuronidase appears in a tear of the injured eye and to a lesser degree in a tear of the contralateral eye as compared to that in a tear of healthy persons. The appearance of acid glycosidases or increase of their activity is connected with the departure of enzymes from the infected cornea and destruction of glycoside-containing compounds being important for the structure and functions of the cornea.

Adolescent↗