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Abstract Background Differences in duration of bone healing in various parts of the human skeleton are common experience for orthopaedic surgeons. The reason for these differences is not obvious and not clear. Methods In this paper we decided to measure by the use of real-time RT-PCR technique the level of expression of genes for some isoforms of bone morphogenetic proteins (BMPs), whose role is proven in bone formation, bone induction and bone turnover. Seven bone samples recovered from various parts of skeletons from six cadavers of young healthy men who died in traffic accidents were collected. Activity of genes for BMP-2, -4 and -6 was measured by the use of fluorescent SYBR Green I. Results It was found that expression of m-RNA for BMP-2 and BMP-4 is higher in trabecular bone in epiphyses of long bones, cranial flat bones and corpus mandibulae then in the compact bone of diaphyses of long bones. In all samples examined the expression of m-RNA for BMP-4 was higher than for BMP-2. Conclusion It was shown that m-RNA for BMP-6 is not expressed in the collected samples at all. It is postulated that differences in the level of activation of genes for BMPs is one of the important factors which determine the differences in duration of bone healing of various parts of the human skeleton.

Comparison of the effectiveness of three techniques used for the programmed augmentation of mandibular bone, which is part of the therapeutic procedure used in pre-prosthetic, pre-implantology surgery. The techniques are based on stimulation of natural events continuously present in living bone, that is, the process of bone remodelling. We compared the effects of stimulation of osteogenesis of alveolar bone by transplants of 1. autologous bone marrow; 2. freshly isolated mononuclear cells from bone marrow containing CD34+ cells; and 3. platelet rich plasma (PRP). It was shown that newly formed bone augmented under the influence of platelet rich plasma shows the closest similarity to the control contralateral bone. Less effective was the treatment by the population of CD-34 bone marrow derived stem cells or autologous bone marrow. It seems that guided bone regeneration of mandibular bone needs the active products as cytokines or growth factors contained in platelet rich plasma. Most probably they are released more quickly after transplantation than from progenitor cells derived from bone marrow. "The gold standard" of autogenic bone grafts was not used, because we believe that if possible, alternative techniques should be applied to avoid additional trauma to patients. [ABSTRACT FROM AUTHOR]

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The diagnosis of renal osteodystrophy (RO) in chronic renal failure (CRF) in everyday practice depends on noninvasive methods. Still there is no widely accepted bone resorption marker in RO. The aim of the study was to evaluate the correlation of serum cross-linked C-terminal telopeptide of type I collagen (s-CTx) as the resorption marker with clinical and biochemical data and to evaluate s-CTx level changes after treatment with low dose of alfacalcidol and calcium carbonate. Sixty patients (36 men and 24 women) with creatinine serum level 3.0 ± 1.5 mg% were examined. The result of s-CTx was normal in 27 patients and increased in 33. There was a significant positive correlation of s-CTx and serum creatinine (p < 0.001), alkaline phosphatase activity (p < 0.05) and duration of CRF (p < 0.05) in men and serum creatinine (p < 0.001) and phosphorus (p < 0.05) in postmenopausal women. Patients with increased s-CTx had significantly higher serum creatinine (p < 0.001), phosphorus (p < 0.01), alkaline phosphatase activity (p < 0.001) and longer duration of CRF (p < 0.001) than patients with normal s-CTx. Next, 25 patients were treated for 6 months with alfacalcidol in dose of 0.25 μg every other day and calcium carbonate in dose of 3.0 μg per day and 25 patients with calcium carbonate only. There was a statistically significant decrease of s-CTx in both groups of patients (p < 0.01). We conclude, that in patients with CRF, s-CTx can be taken as the marker of bone resorption changes after treatment of RO but the value of s-CTx as a diagnostic marker in these patients ought to be evaluated in comparison with histomorphometry.Copyright © 2002 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

High-speed autoradiography with stripping film of H-thymidine-labelled cells was tested. The tests involved: (a) various times of immersion of emulsion-covered cell preparations in the mixture of dioxane-PPO-POPOP, at 20°C, (b) exposure of cell preparations and blanks for various times at either −70°C or +20°C, with different humidity levels. Autoradiographs of good quality could be produced by 2-min immersion in the scintillator, exposure time ≥1 h at either temperature and relative humidity 20-30%. A linear relationship between autoradiographic efficiency and exposure time of 1-7 h was found at either temperature, although the efficiency of autoradiographs exposed at −70°C was by approximately 30% higher than that of autoradiographs exposed at +20°C. Background values of autoradiographs dried with a fan and exposed for 1/4-7h at either −70°C or +20°C were 0.6-0.8 grain/100 μm. Theoretical calculations and experimental data showed that high-speed autoradiographs are 30-50 times more efficient as compared with conventional stripping film autoradiographs, thus allowing a shortening of the respective exposure time. Theoretical aspects of efficiency and resolution of high-speed autoradiography are considered. [ABSTRACT FROM AUTHOR]

Purpose: Arborisation of retinal vessels might be influenced by the physiological activity of the retina. It seems that the pattern of retinal vessels is an obvious object for fractal analysis. The fractal dimension of normal retinas was therefore used by us as a control value for comparison with the values collected from patients with amblyopia in one eye connected with strabismus and normal vision in the other., Methods: The 'box-counting method' was used for calculation of self-similarity dimension in 54 control patients, i.e. comparing 54 left retinas with 54 right ones. Statistical analysis was performed for these groups. This value was therefore used as a control for comparison with the values of fractal dimensions measured in patients with amblyopia connected with strabismus in one eye and normal vision in the other. The retinas of 30 patients with strabismus in one eye and of 1 patient with strabismus in both eyes were analysed., Results: The measurements performed on digitised photos of the retinas of these patients proved statistically significant differences between the control group and the fractal dimensions for the arborisation of retinal vessels in the eyes of patients with normal vision as well as differences in comparison with the retinas of functionally disabled eyes with defective vision connected with strabismus., Conclusion: The final conclusion is not obvious. It seems that normal vision has a statistically confirmed influence on the development of retinal vessels. Defective vision connected with strabismus is disturbing the process of arborisation of the retinal vessels. The retinal vessels of the patient eyes with normal vision differ from the normal pattern as defined by fractal dimensions of control eyes., ((c) 2009 S. Karger AG, Basel.)

Mineral crystallinity of bone tissue is subject to changes during one's development, as well as in many systemic diseases, especially renal osteodystrophy. The aim of the study was qualitative evaluation of the mandibular bone tissue in patients suffering from renal osteodytrophy, treated with renal-replacement therapy: hemo-dialysis or allogeneic kidney transplantation. The mineral crystallinity coefficient was evaluated using electron paramagnetic resonance (EPR) based on the observation that ionizing radiation induces paramagnetic centers in hydroxyapatites. The concentration of these centers was used to establish an indicator of crystallinity rate which is a measure of the crystallinity of tissue mineral. On the basis of these results, it is possible to widen the indications for implantological treatment in specific clinical cases.

Background: The mechanism of heterotopic ossicle formation induced by grafted transitional epithelium, described in several species, has not yet been elucidated. This phenomenon is not species specific, but in xenogeneic systems, immunosuppression of the host is needed to protect the implant long enough for it to exert its osteoinductive potency. We showed a strong correlation between the intensity of bone induction caused by implantation of HeLa cell lines and their ability to synthesize and secrete seven different isoforms of BMPs (bone morphogenetic proteins). We decided to discover whether the urothelium of guinea pig, having high osteoinductive potency, differs in BMP content from human urothelium, which does not induce heterotopic bone., Material/methods: The RT-PCR technique was used to investigate the expression of BMP family genes. PCR products were directly sequenced with an ABI Prism 310 sequencer. The obtained sequences were analyzed using BLAST., Results: Two isoforms of BMP (BMP-3 and BMP-4) were detected in the guinea pig urinary bladder mucosa. The sequences of these products were identified by BLAST analysis and compared with human mRNA and protein. The experiment performed on human urinary bladder mucosa failed to detect the expression of these BMPs, while b-actin mRNA was detected., Conclusions: Our findings explain the reason for the osteoinductive properties of guinea pig urothelium and are in line with the explanation of the osteoinductive properties of HeLa cells. Moreover, human urothelium, which did not express any BMP mRNA, therefore probably lacks osteoinductive competence.

The theoretical and practical aspects of applying stem cells in medicine are discussed.

Unlabelled: The aim of the study was to evaluate the effect of salmon calcitonin on bone mineral density, parathyroid and thyroid C cells, and calcium-phosphate metabolism in chronic hemodialysis patients with uremic hyperparathyroidism. Forty five patients with serum 1-84 PTH >220 pg/ml were divided into 2 groups: group I (n = 25), treated with intranasal salmon calcitonin (200 IU, thrice a week) and control group II (n = 20). Patients received calcium carbonate (up to 6 g/d) alone or with aluminum hydroxide (up to 3 g/d) as phosphate binders; dialysate calcium was 1.75-2 mmol/l. The observation period was 12 months. The following parameters were measured: bone mineral density (BMD) with dual-energy X-ray absorptiometry in: lumbar spine (L2-L4), femoral neck and total body, before and after the study; serum endogenous calcitonin, before and after the study; serum PTH, alkaline phosphatase and total hydroxyproline, before and after 1, 3, 6, and 12 months; and serum calcium and phosphate monthly. During 12 months of the study, a substantial reduction in BMD was observed in all examined regions in group II (-2.8 +/- 2.1%; p<0.01 in L2-L4, -2.4 +/- 2.0%; p<0.01 in femoral neck, and -1.9 +/- 1.4%; p<0.01 in total body), whereas in group I a slight increase of bone mineral was noted, however insignificant. The inhibition of bone resorption was accompanied by a marked decrease in serum hydroxyproline. No changes in parathyroid activity were noted nor any decrease in serum phosphate. The treatment had no influence on serum endogenous calcitonin; initial concentrations were elevated in 47% of patients., Conclusion: Intranasal salmon calcitonin: 1) has no influence on bone mineralization in dialysis patients with uremic hyperparathyroidism; 2) has no significant effect on serum phosphate concentration; 3) provided adequate calcium supplementation doesn't stimulate parathyroid glands; 4) has no influence on endogenous calcitonin secretion.

Monitoring of iron metabolism has become a major clinical issue in end-stage renal patients undergoing hemodialysis. It can be done at three levels: storage, transport and marrow availability. The objective of that study was to evaluate if a combination of an iron storage marker, serum ferritin (SF) with red cell zinc protoporphyrin (ZPP), a marker of iron availability for erythron, will improve diagnostic value of both tests. In a baseline survey in the population of 186 haemodialysis patients (75% treated with rHuEpo), the following parameters were determined: complete blood count, serum transferrin saturation (TSAT), transferrin, SF, hypochromic red cells % (HRC) and ZPP; the ZPP/logSF ratio was calculated. Iron deficiency was defined as a fernitin saturation--TSAT < 20%. In the second part of the study, 24 pts with SF < 50 ng/ml were given 50 mg of i.v. iron weekly for three months, then the same tests were repeated. During that time the doses of rhuEpo were stable. An increase in hemoglobin of > 1.0 g/dl was considered as a positive response. In 186 studied patients mean SF was 274 +/- 335 ng/ml, and mean ZPP was 68 +/- 44 mumol/mol heme. A ZPP/logSF ratio > or = 40 had the best combination of diagnostic sensitivity and specificity in detecting iron deficiency (76% and 83% vs: 56% and 89% for ZPP > 90 mumol/mol heme, 84% and 34% for HRC > 5%, 68% and 58% for HRC > 10%) and the strong correlations with all other examined parameters were found. The index showed also the highest correlation with the response to the i.v. iron (r = 59; p < 0.01) of the tests evaluated. After three months the values of ZPP/logSF ratio decreased from 80 +/- 105 to 39 +/- 19 (p < 0.01). A significant difference between responders and nonresponders was found for basal ZPP/logSF (p < 0.05) but not for ZPP. Our data suggest that the ZPP/logSF index provides a new valuable parameter for the identification of hemodialysis patients with iron deficiency and the prediction an erythropoietic response to iron supplementation.

The results of the studies of hypophyseal-gonadal axis in dialysis women are not uniform. Mostly the increased serum concentrations of prolactine and pituitary gonadotropins are observed; the data about ovarian secretion are much more scanty and contradictory. The aim of this crossectional study was to assess changes in sexual hormones secretion and their associations with menstrual disturbations in premenopausal women with end-stage renal failure undergoing hemodialysis. Sixty three women from six mazovian dialysis units, aged 18-45 years (mean 35 +/- 7 years) were enrolled into the study. They were divided into four groups according to their menstrual pattern: I--eumenorrhoea (n = 17), II--polymenorrhoea (n = 9), III--oligomenorrhoea (n = 16) i IV--amenorrhoea n = 21). There were no differences between both groups in respect to age, age of menarche, time on hemodialysis, and body mass index. In all subjects gynecological examination was performed and serum prolactin, FSH, LH, estradiol, progesterone and testosterone concentrations were assayed. In 49% women high serum prolactin concentrations were noted (the highest in group IV--1699 +/- 1022 vs 441 +/- 205 microIU/ml in group I; p < 0.05). Mean serum FSH and LH were increased in group IV only (33 +/- 59 and 22 +/- 31 mIU/ml); no significant differences among groups examined were seen. Serum estradiol was increased in groups I-III (95 +/- 46, 72 +/- 33, and 83 +/- 55 pg/ml, respectively) and decreased in group IV (27 +/- 22 pg/ml; p < 0.001 in respect to remaining groups). Mean serum progesterone and testosterone concentrations were normal in all four groups, but serum progesterone was significantly lower in groups II-IV than in group I (p < 0.05). No differences in hormonal status between patients receiving and not receiving rHuEpo were observed. Menstrual disturbances are common (73%) in premenopausal women with end-stage renal failure, with amenorrhea constituting a half of them. Hyperprolactinemia is the most frequently seen alteration in their hormonal profile with the highest concentrations in those with secondary amenorrhea. Increased serum gonadotropins and reduced serum estradiol concentrations are mostly seen in amenorrheic women, whereas in menstruating women serum estradiol is often slightly increased.

The mechanism of formation of the maxillary sinuses is not elucidated as yet, although their morphology during embryogenesis is well described. In the prenatal period, the pneumatization hypothesis is not valid. As the molecular approach to this problem is difficult to apply to human samples, we decided to apply immunohistochemical reactions to analyse the synthesis of selected molecules involved in the rebuilding of tissues. Hematoxylin-eosin staining and immunohistochemical reactions for the detection of MMPs (matrix metalloproteinases), one of their inhibitor TIMP 1 (tissue inhibitor of MMPs), BMP 6 (bone morphogenetic protein 6) and TGF-beta (transforming growth factor beta) were performed in the epithelium the mucosa of the maxillary sinuses of several human foetuses from the collection of the Anatomical Institute. The age of the foetuses was 8, 11, 15, 16, 17, 18 and 22 weeks. An intense positive reaction for MMPs 1, 2 and 3 was found in the mucosal epithehum of developing sinuses in the whole series of foetuses was found. The reaction was more intense in advanced stages of foetal development. Tissue derived inhibitor TIMP was hardly detectable, regardless of the age of samples. However, the intensity of the reaction for TGFbeta was strong in both young and more mature sinus epithelium. The presence of BMP 6, a member of the superfamily of TGFbeta, was detected although the intensity of this reaction in the epithelium was rather weak. Both TGFbeta and BMP 6 are well known as regulators of differentiation in the course of organogenesis. Results of the histochemical analysis suggest the possible involvement of the epithelium in the growth and formation of the maxillary sinuses. The main argument for this is intense reaction for MMP proteases which, as in bone, regulate the turnover and rebuilding processes of the extracellular matrix (ECM).