Biomedical subjects

M Marková

Publications and source records attributed to M Marková.

At least 19 recordsLinked to original sources

PubMed2005

Third molar as an age indicator in young individuals.

The authors developed a method of chronological age estimation in young individuals on the basis of third molar developmental stage. The new method is based on the finding that time course of third molar development depends on the number of assessed third molars. That means, in individuals with 1 to 3 third molars agenesis the development of founded third molars is delayed in comparison with individuals having all third molars present. This difference is statistically significant. Retardation of development is directly proportional to the number of congenitally missing third molars. Chronological age corresponding to individual stages of third molar development was calculated separately for individuals with all four third molars present and separately for individuals with 1 to 3 third molars agenesis. With this division it was possible to decrease the error of age estimation to 1.63 years in the group of individuals with all four third molars present and to correct the age underestimation in individuals with agenesis. The elaborated method of chronological age estimation in young individuals shows incomparably much more accuracy in contrary to methods used in adults. In addition this new method is distinguishing by maximum simplicity.

Adolescent↗

PubMed2004

Agenesis of third molars in young Czech population.

The aim of this study is to evaluate the incidence of third molars agenesis in the Czech population. One thousand patient's panoramic radiographs of the pedostomatological department of Second Stomatological Clinic of The First Faculty of Medicine, Charles University, has been analyzed. The age of probands was ranging between 12 to 21 years inclusive. Patients were divided into 10 groups according to age. In each age group were 100 individuals - 50 boys and 50 girls. Agenesis of 1-4 third molars was present in 22.5% (25.6% in boys and 19.4% in girls). Intersexual difference is significant. Further, the incidence of third molars agenesis in individual dentition quadrants, upper and lower jaw and right and left side of dentition was examined. Neither in boys nor in girls were detected significant differences in these values. Agenesis of just one, any third molar occurs in 10.9% (12.0% in boys and 9.9% in girls). For one individual it is mean 1.9 congenitally missing third molars in boys and 2.0 congenitally missing third molars in girls. These intersexual differences are not significant. In boys, the most frequent agenesis was of one, next of two, then of three and at last of four third molars. In girls, agenesis of two was on the first place, then that of one and lastly and equally of three and of four third molars. The results were compared with literature data.

Adolescent↗

PubMed2004

[Hypoplasia of trachea with tracheal bronchus as a complication of surgical correction of tetralogy of Fallot].

A 10 months old infant underwent repair of tetralogy of Fallot with hypoplastic annulus of the pulmonary valve, diminutive pulmonary arteries, right aortic arch and left superior vena cava. The right ventricular outflow tract was reconstructed using a monocusp patch. The postoperative course was unfavourably influenced by respiratory complications due to tracheal bronchus and hypoplasia of trachea, which were not diagnosed preoperatively. Extreme emphysema of the right upper and middle lobes compromised haemodynamics. Repeated reoperations were required. The upper and the middle lobes of the right lung had to be resected, the hypoplastic trachea reconstructed with a pericardial patch and pulmonary homograft inserted. One year later, homograft had to be replaced and tricuspid annuloplasty performed for pulmonary and tricuspid regurgitation and right ventricular dilatation as a consequence of increased pulmonary artery pressure. Three years after the original surgery the patient remains in good clinical condition.

Humans↗

PubMed2004

Thrombelastography monitoring of platelet substitution therapy and rFVIIa administration in haemato-oncological patients with severe thrombocytopenia.

Thrombocytopenic patients refractory to platelet concentrates (PC) could be treated during bleeding episodes with the recombinant activated FVII (rFVIIa). However, monitoring of administration of the rFVIIa or a response to platelet substitution therapy in thrombocytopenia patients is not well documented so far. Using of whole blood ROTEG analysis we monitored the changes in haemostatic parameters following in vivo platelet concentrate administration compared to ex vivo rFVIIa administration in patients with a severe to mild thrombocytopenia secondary to haemato-oncological disease. We use non-activated thrombelastography (NATEG) and a mild intrinsic activation thrombelastography (INTEG). NATEG analysis was sufficiently sensitive to monitor changes following PC and rFVIIa administration. Both, platelet infusion and rFVIIa treatment induced significant shortening of clotting time (CT) and clot formation time (CFT) parameters (p<0.05). When we compared the effect of platelet vs. rFVIIa treated whole blood by NATEG analysis we did not found any significant difference. Analysis with INTEG system was less sensitive and changes in CT and CFT were not significant. The monitoring with thrombelastography could enable efficient application of platelet concentrate and furthermore the using of rFVIIa as an alternative treatment of patients refractory to platelet infusion or with allergic reactions.

Adult↗

PubMed2004

Development of third molar in the Czech population.

The third molar development was studied on the basis of 1700 panoramic radiographs analysis of randomly selected individuals in the age ranging between 5-21 years inclusive. Each age group consisted of 100 probands--50 boys and 50 girls. The characteristics of the third molar development were following: time of dental follicle formation--dynamics of development--the most frequent stages of third molar development in individual age groups-- intraindividual differences and symmetry of development--incidence of 1-4 third molars agenesis--relation between the third molar development and the dental age--differences in the third molar development between individuals with all four third molars present and individuals with 1-3 third molars agenesis--ntersexual differences. On the basis of our analysis of seven stages of development, differences of this process between males and females and the changes in dynamics of development characterizing upper and lower jaw were described. The incidence of the third molar agenesis was statistically significant, being more frequent in boys (24.2%) than in girls (17.6%). The study showed, that when the third molar is not present at the age of thirteen, it could be taken in the Czech population as agenesis. Correlation between developmental stage of third molars and dental age was ascertained. With the exception of the agenesis, no other statistically significant intersexual differences were found.

Adolescent↗

PubMed2003

Anomalous maxillary lateral incisor--the only product of dental lamina, difficult classifiable in the time. Symptom of hypodontia syndrome non-described until present time.

The authors described anomalous development of maxillary lateral incisor non-yet published in stomatologic literature. Diagnostics and clinical findings of the anomaly and the prognosis of the affected tooth they based on the description of six longitudinal observed patients. The principal symptom of the anomaly is the disturbance of time-plan of the tooth development. Terms of the tooth mineralization, the time of eruption and root completion cannot be included either in deciduous or in permanent dentition. The tooth is the only product of the dental lamina; it has no predecessor or successor. Frequent disturbances of the eruption pathway result often in anomalous position of the tooth. Taking into consideration the fact that the anomaly appeared always in connection with hypodontia syndrome, it is possible to consider it to be the symptom of hypodontia syndrome. This fact is more significant as it enables to establish the diagnosis of hypodontia syndrome already in early deciduous dentition.

Adult↗

PubMed2003

NMU-induced mammary carcinogenesis in female rats is influenced by repeated psychoemotional stress.

Epidemiological and experimental studies indicate psychoemotional stress as an important factor in carcinogenesis. The aim of this study was to evaluate the effect of restraint stress on N-nitroso-N-methylurea (NMU)-induced mammary carcinogenesis. Female Sprague-Dawley rats were injected with two intraperitoneal NMU doses each per 50 mg/kg b.w. between 39-49 postnatal days. Three experimental groups were created: 1. NMU (without restraint--control group, 12 animals), 2. NMU+1IMS (group with single restraint, IMS--immobilization stress, 12 animals), 3. NMU+7IMS (group restrained 7 times during a week, 12 animals). Animals were immobilized daily in special boxes for 120 minutes or 7 x 120 minutes, respectively from third day after carcinogen administration. The observation lasted for 20 weeks. The incidence, frequency, latency and volume of mammary tumors were evaluated. In repeatedly immobilized group NMU+7IMS increase in tumor incidence by 57% (p<0.05), marked increase in frequency per group by 153% (p<0.01), increase in frequency per animal by 61% and shortened latency period by 7 days were recorded. The effect of single restraint was not seen. In this experiment repeated immobilization carried out early after carcinogen administration had a remarkable stimulatory effect on chemically-induced mammary carcinogenesis in female rats.

9,10-Dimethyl-1,2-benzanthracene↗

PubMed2002

Variability of mammary carcinogenesis induction in female Sprague-Dawley and Wistar:Han rats: the effect of season and age.

It is important to determine and clarify the variability of mammary carcinogenesis induction in animal experimental studies particularly in connection with chemoprevention projects. The circannual seasonal rhythms of hormone levels or various parameters within the immune system may involve factors participating in mammary gland carcinogenesis. In our study, 19 experiments were conducted and all of them lasted for about 25 weeks after chemical carcinogen administration (DMBA or NMU) under standard laboratory conditions. Females of two rat strains - a medium susceptible Sprague-Dawley strain and a very low susceptible Wistar:Han were used. We observed not only the effect of seasonal changes but also the effect of age after single or repeated carcinogen administration. The seasonal dependence of mammary carcinogenesis with higher tumor incidence during long days in comparison with winter short days has been demonstrated in Sprague-Dawley rats. In experiments on the Wistar:Han strain, certain features of seasonal character were recorded, although the very low susceptibility of this strain to mammary carcinogenesis might have influenced the results. A limited period of carcinogen administration in early puberty around postnatal days 43-46 (higher susceptibility), when compared to the period after postnatal day 50, is the factor significantly increasing incidence and frequency of mammary carcinogenesis in the Sprague-Dawley strain. Our results indicate the need to consider the effect of season and age of animals at the time of carcinogen administration on rat mammary carcinogenesis induction. However, the application of the results obtained in one strain of experimental animals may only lead to misleading conclusions.

Age Factors↗

PubMed2001

[Effect of sideropenic anemia and its therapy on serum levels of leptin].

BACKGROUND: Leptin is a protein hormone produced predominantly by adipocytes. Its major role in human body is probably to regulate the food intake through the hypothalamic satiety center. One of the peripheral effects of leptin, which was studied mainly in vitro so far, is its stimulating effect on the haematopoietic stem cells. The information concerning the changes of serum leptin levels in various haematological diseases is very limited. The aim of our study was to explore changes of serum leptin levels in patients with sideropenic anaemia at the time of diagnosis and in the various phases of their treatment. METHODS AND RESULTS: 18 patients with untreated sideropenic anaemia (SA) and 20 healthy age, gender and weight-matched control subjects were included into the study. The blood testing in SA patients was performed before anaemia treatment, at the time of maximal increase of reticulocytes and after haemoglobin levels normalisation. Blood count, serum leptin, erythropoietin (EPO) and transpherine receptor (TfR) levels were estimated in all samples. Basal serum leptin levels in SA patients did not differ significantly from those of control subjects (13.9 +/- 14.6 SD vs 10.4 +/- 8.8 SD ng.ml-1). Treatment anaemia of did not significantly affect the serum leptin levels in SA patients (13.9 +/- 14.6 SD vs 12.9 +/- 12.6 SD vs 12.8 +/- 15.1 SD ng-ml-1). Serum EPO and TfR levels in SA patients were higher before the start of treatment and decreased significantly after the anaemia recovery. In both groups serum leptin levels correlated positively with body mass index. No unambiguous statistically significant relationships between serum leptin levels and blood count parameters or serum EPO and TfR levels were found in any of the groups studied. CONCLUSION: Neither the changes of red blood cell count during the sideropenic anemia treatment nor the increased erythropoiesis affect significantly serum leptin levels.

Adult↗

PubMed2001

[Exchange of dentition and its control. Overview of current knowledge and personal experience].

Physiological dentition exchange is often interfered with exogenous and endogenous factors. For this reason it must be steadily regulated. The authors present complex view on this topic based on literature studies and own experiences. The authors define fundamental principles "guided exchange", "tooth eruption" and "eruption path". Correct explication of these ideas is necessary for text understanding. Dentition exchange is considered as complex of eruption interactions of individual permanent teeth including molars. The project is based on idea that dentition exchange time is optimal for preventive interventions. At the end the authors underline the importance of global application of the above-mentioned principles on the whole child population.

Child↗

PubMed2000

[Relation between serum leptin levels, blood parameters and erythropoietin levels in hemodialyzed patients].

BACKGROUND: Serum leptin levels are significantly increased in hemodialysed patients compared to healthy subjects. There are some data suggesting the possible relationship of leptin and the regulation of haematopoiesis. The aim of our study was to compare serum leptin levels in two groups of hemodialysed patients: the group treated by recombinant human erythropoietin (n = 40) (HD + EPO), the group without erythropoietin treatment (HD) and the control group of healthy subjects (n = 20) to explore the influence of erythropoietin treatment on serum leptin levels. METHODS AND RESULTS: The tendency towards lower body fat content and higher serum leptin levels was found in both groups of HD patients compared to control group, but the differences did not reach statistical significance due to high variability of those parameters (leptinu levels: HD 19.5 +/- 18.5, HD + EPO 24.9 +/- 23.3, K 10.4 +/- 8.8 ng.ml-1). The erythrocyte count and haemoglobin levels in both groups of HD patients were significantly lower than in control group. The erythrocyte count and haemoglobin levels were significantly lower in HD patients treated by erythropoietin compared to untreated HD group. The leptin/body fat content ratio was significantly higher in HD patients compared to healthy subjects (HD 0.86 +/- 0.72, HD + EPO 0.92 +/- 0.78, K 0.35 +/- 0.21, p < 0.05). Serum leptin levels in all studied groups correlated positively with body fat content and negatively with erythrocyte count. No significant relationships of serum leptin levels to erythropoietin levels or other parameters studied were found in any of groups. CONCLUSIONS: Our study further supported the fact that serum leptin levels in HD patients are relatively higher than in healthy subjects. Serum leptin levels in HD patients treated by recombinant human erythropoietin did not significantly differ from HD patients without this treatment. Except of the negative correlation between serum leptin levels and the erythrocyte count no statistically significant relationships of serum leptin levels and the blood count parameters were found.

Blood Cell Count↗

PubMed2000

[Is leptin physiologically important in the regulation of hematopoiesis?].

Leptin is a protein hormone produced predominantly by adipocytes. Its serum concentrations under stabilised energy balance reflect the total body fat content. Serum leptin levels represent an important peripheral signal informing the hypothalamic satiety center about the body fat stores. Apart from the above mentioned functions the possible physiological significance of leptin in the regulation of angiogenesis, blood pressure, sexual maturation etc. is suggested. The long isoform of leptin receptor belongs to the cytokine receptors group. The leptin receptors were identified in some haematopoietic stem cells. Leptin was found to stimulate the proliferation of haematopoietic stem cells either alone or in combination with some cytokines. Leptin thus seams to represent an additional factor that plays a role in the haematopoiesis regulation as it was demonstrated by some experimental studies. However, this suggestion needs to be further confirmed by clinical studies exploring the changes of serum leptin levels in various phases of haematological diseases and during their treatment.

Animals↗

PubMed2000

Increase of adhesion molecules, fibrinogen, type-1 plasminogen activator inhibitor and orosomucoid in growth hormone (GH) deficient adults and their modulation by recombinant human GH replacement.

OBJECTIVE: GH deficiency (GHD) is usually associated with a higher incidence of cardiovascular disease (CVD). The aim of this study was to establish whether patients with GHD, like those with CVD, show an increase in fibrinogen (FBG), type-1 plasminogen activator inhibitor (PAI-1), acute phase response proteins (APR), and soluble adhesion molecules. The effect of recombinant human GH (rhGH) replacement, on these parameters was also investigated. PATIENTS AND DESIGN: Concentrations of PAI-1 antigen (Ag), adhesion molecules sE-selectin, sP-selectin, and intercellular adhesion molecule-1 (sICAM-1), FBG and levels of APR orosomucoid (ORM), and 'negative APR' transferrin (TRF) were established in 11 panhypopituitary (PHP) patients (eight men and three women, age median 39.0 years, body mass index (BMI) 27. 49 +/- 3.89 kg/m2) before and after 12-month replacement with rhGH. Control values were obtained by examination of 33 healthy age and sex matched subjects (24 men and nine women with BMI 24.16 +/- 1.99 kg/m2). RESULTS: PHP patients had higher concentrations of ORM (0.80 +/- 0.25, vs. 0.61 +/- 0.20 g/l; P = 0.05), FBG (3.22 +/- 0.48, vs. 2.57 +/- 0.47 g/l; P = 0.001), PAI-1 Ag (97.12 +/- 33.23, vs. 44.11 +/- 21.40 microgram/l; P = 0.001), sE-selectin (72.42 +/- 28.35, vs. 42. 80 +/- 12.60 microgram/l; P = 0.004), sP-selectin (221.26 +/- 75.12, vs. 104.79 +/- 26.01 microgram/l; P = 0.001) sICAM-1 (409.75 +/- 137.78, vs. 228.10 +/- 37.54 microgram/l; P = 0.001), and lower levels of TRF (2.14 +/- 0.40, vs. 2.76 +/- 0.39 g/l; P = 0.001) than controls. After 12-month rhGH replacement the patients showed an increase of TRF (2.64 +/- 0.84 g/l, P = 0.037) and decrease of soluble adhesion molecules (sE-selectin 57.98 +/- 27.04 microgram/l, P = 0.01, sP-selectin 121.74 +/- 50.42 microgram/l, P = 0.007; and sICAM-1 279.95 +/- 88.32 microgram/l, P = 0.005), which then, similarly to the ORM (0. 67 +/- 0.12 g/l) and FBG level (2.82 +/- 0.51 g/l), did not statistically differ from the values in the control group. CONCLUSION: rhGH replacement led to modulation of the 'inflammatory response' in panhypopituitary patients. This modulation occurred locally at vascular endothelium level where after rhGH replacement, sE-selectin, sP-selectin and sICAM-1 concentrations decreased, a similar effect as in the systemic inflammatory response, as was also apparent from the changes in acute phase response protein levels.

Adult↗

PubMed2000

Serum leptin levels in diabetic patients on hemodialysis: the relationship to parameters of diabetes metabolic control.

Leptin is a protein hormone produced predominantly by adipocytes that affects food intake and energy expenditure. Its serum levels are significantly higher in patients with chronic renal failure compared to healthy subjects. The aim of this study was to compare serum leptin levels in hemodialyzed patients with type II diabetes mellitus (n=26) with body content-matched hemodialyzed patients without diabetes (n=26) and to explore the relationship between parameters of the long term diabetes metabolic control and serum leptin levels. Serum leptin levels in diabetic patients did not significantly differ from those of non-diabetic patients (25.3+/-8.8 vs 25.7+/-8.7 ng/ml). Serum leptin levels in diabetic patients positively correlated with body fat content, body mass index and predialysis serum insulin levels. No significant relationship were observed between serum leptin levels and blood glucose, glycated hemoglobin, glycated protein, serum urea, creatinine, leukocyte count and total hemoglobin respectively. The multiple stepwise regression analysis revealed that body fat content together with body mass index accounted for 77.8% of variations in predialysis serum leptin levels, while insulin levels and the parameters of diabetes metabolic control had only slight prediction value for leptin concentrations. We conclude that serum leptin levels in hemodialysed patients with type III diabetes mellitus do not significantly differ from those of hemodialysed non-diabetic patients. The body fat content and body mass index are the strongest predictors of serum leptin levels, while parameters of long term diabetes metabolic control play probably only minor direct role in its regulation.

Blood Glucose↗

PubMed2000

Serum leptin levels in patients with sideropenic and pernicious anemia: the influence of anemia treatment.

Leptin is a 16 kDa protein hormone involved in food intake, energy expenditure regulation and numerous other physiological processes. Recently, leptin has been demonstrated to stimulate hematopoietic stem cells in vitro. The aim of our study was to measure serum leptin and erythropoietin levels in patients with sideropenic (n = 18) and pernicious anemia (n=7) before and during anemia treatment. Blood samples for the blood count, leptin and erythropoietin determinations were obtained by venepunction at the time of the diagnosis of anemia and after partial and complete anemia recovery. The relationships of serum leptin levels to erythropoietin levels and blood count parameters were also studied. No significant differences in serum leptin levels between the groups studied were found. The serum leptin levels in none of groups were modified by treatment of anemia (basal levels, the levels during treatment and after anemia recovery were 13.1+/-14.5 vs 12.8+/-15.6 vs 12.0+/-14.8 ng/ml in patients with sideropenic anemia and 7.8+/-8.5 vs 9.5+/-10.0 vs 8.9+/-6.6 ng/ml in patients with pernicious anemia). The erythropoietin levels were higher at the time of anemia in both groups and decreased significantly after partial or complete recovery. Serum leptin levels in both groups correlated positively with the body mass index. No significant relationships were found between serum leptin levels and erythropoietin values or various parameters of the peripheral blood count. We conclude that serum leptin levels in patients with sideropenic and pernicious anemia positively correlate with the body mass index but are not influenced by the treatment of anemia.

Adult↗

PubMed1999

[Initial experience with surgical treatment of tracheal stenosis in small children using extracorporeal circulation].

Severe tracheal stenosis represents a life threatening malformation which necessitates early surgery. Two patients aged one and two years, respectively, were followed-up for signs of congenital stridor. Following respiratory infection both children became critically ill with severe dyspnoea necessitating intubation and artificial ventilation. In the first patient, echocardiography, tracheobronchoscopy and other investigations revealed a pulmonary artery sling with tracheal compression and hypoplasia of the whole trachea. In the second child, presence of a short local tracheal stenosis was found, the cause of which could not be clarified. In the patient with the pulmonary sling, resection and reimplantation of the anomalous left pulmonary artery was performed first. In both children, however, surgical reconstruction of the lower airways was necessary. Surgery was performed from a midline sternotomy approach in extracorporeal circulation. The hypoplastic trachea with circular rings in the first child was enlarged with a pericardial patch. In the second child, the local tracheal stenosis was resected and a direct anastomosis of the trachea was performed. In both patients, transient formation of granulations was observed. Both children, however, survived and their clinical condition remains good 18 and 9 months, respectively, after surgery. Tracheobronchoscopic controls show very good result. Our experience confirms the possibility of successful surgical reconstruction of lower airways in young children using extracorporeal circulation. Good interdisciplinary cooperation between the surgeon and other specialists is an important prerequisite of good surgical results.

Child, Preschool↗

PubMed1999

Studies on agenesis of third molars amongst populations of different origin.

This study contains information on the occurrence of agenesis of one to four third molars among the population and ethnic groups of Europe, North America, Africa and Asia (Japan), based on the results of investigations carried out by dozens of authors. Recent discoveries have been supplemented with corresponding data concerning the skeletal remains of the jaws of individuals living from the ice age to the middle ages. The results show unbelievably large diversities as regards the frequency of agenesis of third molars in different populations from practically zero (Tasmania) to nearly 100% (Mexican Indians). This remarkable fact is not, however, the only reason why the problem of third molars remains a major concern for anthropologists, anatomists and stomatologists. Indeed, agenesis of third molars present only one of the most important anomalies which characterizes this tooth. It is necessary to look for the roots of the said variability in the remarkably complicated phylogenetic development undergone by the third molar from the time of our predecessors to the present day. Most of today's authors are of the opinion that although significant involution changes have occurred in third molars, that with the advent of hominization the number of teeth in individuals has stabilized at eight for every quadrant of dentition. For this reason it is not possible to regard agenesis of third molars as the manifestation of the phylogenetic reduction in the number of teeth, but as the developmental anomaly which is the result of a mutation and selection process based on heredity. The results are completed with an analysis of the value of agenesis of one to four third molars according to the individual quadrants and gender. A knowledge of these indicators is necessary in order to study the relationship between agenesis of third molars and hypodontia of the other teeth.

Biological Evolution↗

PubMed1998

[Can normalization of vascular cytoadhesive activity be explained by the anti-atherosclerosis effect of growth hormone?].

BACKGROUND: The increased mortality caused by premature atherosclerosis has been shown among patients with hypopituitarism receiving conventional hormone treatment but with unsubstituted growth hormone deficiency. This experience belongs among the most important arguments in favour of replacement with growth hormone. The mechanisms of the antiatherogenic effect of growth hormone are poorly understood. The protective effect of growth hormone on the vascular endothel and its intervention in the clotting process, which have not been yet elucidated, may be the causative factors. METHODS AND RESULTS: The endothelial damage as given by measuring of circulating soluble cytoadhesive molecules sE-selectin, sP-selectin and intercellular adhesive molecule 1 (ICAM 1) was measured in 15 adult panhypopituitaric patients before and after 1 year treatment with recombinant human growth hormone. The blood levels of all of these cytoadhesive molecules decreased significantly (p < 0.01) during the treatment. None of the concomitantly followed coagulation tests (prothrombin time, activated partial thromboplastin time, fibrinogen, antithrombin III, von Willebrand's factor and D-dimer) was significantly changed during the treatment. The tendency to decrease (p = 0.054) was observed with antithrombin III. CONCLUSIONS: The decrease of circulating cytoadhesive molecules in blood during the treatment of growth hormone gives evidence for its protective effect, either direct or mediated, on the vascular endothel. These findings could bring an explantation for the premature atherosclerotic changes in hypopituitarism and antiatherogenic effect of growth hormone.

Adult↗