Changes in articular cartilage and subchondral bone histomorphometry in osteoarthritic knee joints in humans

In this study, we have examined the correlation between the histological and histochemical changes of articular cartilage and bone parameters of the underlying subchondral bone. The aim was to elucidate patterns of bone parameter changes within different depths of subchondral bone in the joints with macroscopically normal cartilage and in joints with osteoarthritis (OA). Ten tibial plateaus were taken from patients during total knee replacement surgery due to severe OA. They were compared with 10 sets of tibial condyles obtained from autopsy subjects with no history of bone or joint disease. The cylindrical cartilage-bone samples were taken out from the anterior, posterior, external, and internal areas of the condyles for cartilage assessment (Mankin score) and subchondral bone histomorphometry. Four histomorphometric parameters were measured: bone volume (BV/TV), trabecular thickness (Tb.Th), trabecular number (Tb.N), and trabecular separation (Tb.S). Our study showed that subchondral bone from the OA group had significantly higher bone volume (54.1 +/- 10.6%) than control group (37.8 +/- 8.1%) (P < 0.01). In addition, trabecular parameters from the OA subchondral bone showed a smaller number of sparsely distributed and thicker trabecules than in control group (P < 0.05). Medial and lateral condyle from the control group did not differ significantly, while medial condyle from OA group showed a high increase of bone volume (62.8 +/- 13.3) and consecutively different trabecular parameters when compared with the lateral condyle from the same group. Also, it was shown that there are regional differences (anterior, posterior, internal, and external) in bone parameters between both condyles within both, control and OA groups. Comparison of bone parameters from three different stage of articular cartilage degeneration (Mankin score) showed that higher degree of cartilage degeneration is followed by significant changes in subchondral bone architecture. Furthermore, we have found that progression of cartilage degeneration leads to changes in bone parameters which affected deeper levels of subchondral bone. According to these results, it can be suggested that changes in histomorphometric parameters of subchondral bone are secondary to cartilage damage and proceed deeper into subchondral bone with increasing cartilage degeneration.

Expression of bone morphogenetic proteins and cartilage-derived morphogenetic proteins during osteophyte formation in humans

Bone- and cartilage-derived morphogenetic proteins (BMPs and CDMPs), which are TGFbeta superfamily members, are growth and differentiation factors that have been recently isolated, cloned and biologically characterized. They are important regulators of key events in the processes of bone formation during embryogenesis, postnatal growth, remodelling and regeneration of the skeleton. In the present study, we used immunohistochemical methods to investigate the distribution of BMP-2, -3, -5, -6, -7 and CDMP-1, -2, -3 in human osteophytes (abnormal bony outgrowths) isolated from osteoarthritic hip and knee joints from patients undergoing total joint replacement surgery. All osteophytes consisted of three different areas of active bone formation: (1) endochondral bone formation within cartilage residues; (2) intramembranous bone formation within the fibrous tissue cover and (3) bone formation within bone marrow spaces. The immunohistochemistry of certain BMPs and CDMPs in each of these three different bone formation sites was determined. The results indicate that each BMP has a distinct pattern of distribution. Immunoreactivity for BMP-2 was observed in fibrous tissue matrix as well as in osteoblasts; BMP-3 was mainly present in osteoblasts; BMP-6 was restricted to young osteocytes and bone matrix; BMP-7 was observed in hypertrophic chondrocytes, osteoblasts and young osteocytes of both endochondral and intramembranous bone formation sites. CDMP-1, -2 and -3 were strongly expressed in all cartilage cells. Surprisingly, BMP-3 and -6 were found in osteoclasts at the sites of bone resorption. Since a similar distribution pattern of bone morphogenetic proteins was observed during embryonal bone development, it is suggested that osteophyte formation is regulated by the same molecular mechanism as normal bone during embryogenesis.

Bone morphogenetic protein-7 reduces the severity of colon tissue damage and accelerates the healing of inflammatory bowel disease in rats

Bone morphogenetic protein-7 (BMP-7) is a growth and differentiation factor and belongs to the TGF-beta superfamily of proteins. Previous studies have shown an abundant expression of BMP-7 in the developing intestine and an association with a perturbed BMP/SMAD downstream signaling leading to a malignant phenotype and inflammation in the gut. In the present study, we have evaluated the effect of systemically administered recombinant human BMP-7 against trinitrobenzenesulfonic (TNBS) acid induced inflammatory bowel disease (IBD) in rats. The TNBS administered rats treated with BMP-7 have developed much less severe form of colitis based on macroscopic and histological scoring when administered 1.5 h before or 24 h after colitis induction. Bioavailability studies in healthy rats have revealed that significant portion (3.6%) of i.v. administered BMP-7 is targeted for BMP-7 receptors in the stomach and ileum, respectively, suggesting its availability to target tissue upon administration. Immunohistochemical and RT-PCR analyses have shown elevated expression of pro-inflammatory (IL-6, TNF-beta, ICAM-1) and pro-fibrogenic (TGF-beta) cytokines, and BMP-7 treatment significantly reduced their expression in the intestine; among which the suppression of IL-6 appeared to be the most important. Taken together, the results of this study suggest that BMP-7 plays an important role in the regulation of anti-inflammatory response in the adult gut tissue.

Microstructural alterations of femoral head articular cartilage and subchondral bone in osteoarthritis and osteoporosis

OBJECTIVE

Explore whether osteoporosis (OP) in humans influences the morphological status of the articular cartilage and the subchondral bone. Explore the relationship between the macroscopic aspect of the articular surface and the rate of microscopic changes of both the cartilage and the subchondral bone in OP and osteoarthritis (OA).

METHODS

Femoral heads after total hip replacement were obtained from patients with OP or hip OA (OP, n = 56; OA, n = 12). Cartilage degeneration was assessed using the Mankin grading system whereas subchondral bone was evaluated using histomorphometry and Micro-computed Tomography (μCT) scanning system. Thickness of the cartilage layers and subchondral cortical bone (SCB) was measured.

RESULTS

Samples with higher total Mankin score have significantly reduced cartilage thickness. Mankin score differed between all OP specimens. In OP samples with lower Mankin scores the thickness of SCB shows a trend of an increase caused by increased levels of bone remodeling. In OP samples with higher Mankin scores we observed thinning of SCB. Structural indices of subchondral trabecular bone (STB) were significantly lower in OP than in OA samples.

CONCLUSION

Thinning of SCB, found in OP samples with higher Mankin scores could be related with the progression of the cartilage degeneration indicating an early-stage OA. Increased levels of bone remodeling and evidently changed morphology of subchondral bone found in OP samples with lower Mankin score indicated that bony bed level must have a role in the progression of the cartilage degeneration.

Variations of the great arteries in the carotid triangle

The variations of the common carotid artery, as well as of the external and internal carotid arteries, are described. During anatomic dissection on adult cadavers, we investigated the variability of appearance of 40 carotid arterial systems. Special consideration was given to the topographic relations such as the level of the bifurcation of the common carotid artery, the relationship between the external and internal carotid arteries, and the origin of the great collateral branches. Special attention was paid to the origin of the superior thyroid artery. In this article the practical importance of these variations is stressed.

Osteopontin expression correlates with nuclear factor-κB activation and apoptosis downregulation in clear cell renal cell carcinoma

Osteopontin (OPN) is a phosphoglycoprotein implicated in tumorigenesis and tumor cell metastasis. Apoptosis inhibition is one of the mechanisms that contribute to development and progression of cancer, and might be initiated by OPN interaction with tumor cells. The aim of this study was to analyze the relation between OPN and nuclear factor-kappa B (NF-κB) expression in clear cell renal cell carcinoma (CCRCC), as well as their relation to apoptotic activity of tumor cells. Expression of OPN protein and p65 NF-κB subunit was analyzed immunohistochemically in 87 CCRCC samples, and compared mutually and with apoptotic index. Expression of OPN mRNA was analyzed using quantitative real-time PCR and compared with OPN and NF-κB protein expression in 22 CCRCC samples. Statistical analysis showed an association of p65 NF-κB with OPN mRNA (p=0.015) and protein (p<0.001). Also, we found an inverse relationship of OPN with NF-κB protein expression and apoptotic activity of tumor cells (p=0.006 and p=0.022, respectively). Our results indicate that p65 NF-κB signaling pathway may be involved in OPN-mediated CCRCC progression, partly by protecting tumor cells from apoptosis. Therefore, both molecules can constitute potential targets for therapeutic intervention in CCRCC.

Hypothyroidism and Nonalcoholic Fatty Liver Disease: Pathophysiological Associations and Therapeutic Implications

Nonalcoholic fatty liver disease (NAFLD) is a complex clinical entity which can be secondary to many other diseases including hypothyroidism, characterized by lowering of thyroid hormones and increased thyroid stimulating hormone (TSH). A lot of emerging data published recently advocates the hypothesis that hypothyroid induced NAFLD could be a separate clinical entity, even suggesting possible treatment options for NAFLD involving substitution therapy for hypothyroidism along with lifestyle modifications. In addition, a whole new field of research is focused on thyromimetics in NAFLD/NASH treatment, currently in phase 3 clinical trials. In this critical review we summarized epidemiological and pathophysiological evidence linking these two clinical entities and described specific treatment options with the accent on promising new agents in NAFLD treatment, specifically thyroid hormone receptor (THR) agonist and its metabolites.

Age- and region-dependent changes in human lumbar vertebral bone: a histomorphometric study

STUDY DESIGN

Histomorphometric evaluation of autopsy material.

OBJECTIVES

To explore region-dependent changes that occur with aging in trabecular and cortical bone of the human vertebral body.

SUMMARY OF BACKGROUND DATA

Human vertebral bone is continuously subjected to external forces (loads) that promote changes in inner architecture. This functional adaptability is limited, however, and when lost, vertebral bone progressively deteriorates and becomes subject to injury with increases in mechanical loading.

METHODS

Bone cylinders were drilled with a trephine from three regions (central anterior, central posterior, and lateral) of the third lumbar vertebral bodies of 48 autopsy cases 31 to 76 years old. Two consecutive 5-microm sections obtained 150 microm apart were stained with toluidine blue and Masson trichrome and photographed at x40. Differences in numerous morphometric factors were evaluated by age and region of the vertebra using repeated-measures analysis of variance and Tukey's Honestly Significant Difference test.

RESULTS

Starting at about 50 years of age, significant, linearly progressive decreases occurred in trabecular and cortical bone volume (P < 0.005), trabecular surface area (P < 0.001), number of trabeculae (P < 0.001), and thickness of trabeculae (P < 0.001). Space between trabeculae increased from ages 31 to 70 years and then decreased (P < 0.001). Trabecular deterioration was significantly more pronounced in central versus lateral regions (P < 0.001). Cortical bone thickness decreased significantly with aging in central regions but increased in lateral regions between ages 61 and 70 years (P < 0.001).

CONCLUSIONS

The balance between cortical and trabecular bone maintains the strength of the vertebral body until about the age of 50 years, when irreversible deterioration begins in central regions and subsequently involves lateral regions.

BMP signaling in rats with TNBS-induced colitis following BMP7 therapy

Beyond stimulating bone formation, bone morphogenetic proteins (BMPs) are important in development, inflammation, and malignancy of the gut. We have previously shown that BMP7 has a regenerative, anti-inflammatory, and antiproliferative effect on experimental inflammatory bowel disease (IBD) in rats. To further investigate the BMP signaling pathway we monitored the effect of BMP7 therapy on the BMP signaling components in the rat colon during different stages of experimentally induced colitis by 2,4,6-trinitrobenzene sulfonic acid (TNBS). The results showed a significantly decreased BMP7 expression in the acute phase, followed by a significantly increased BMP2 and decreased BMP6 expression during the chronic phase of colitis. BMP7 therapy influenced the expression of several BMPs with the most prominent effect on downregulation of BMP2 and upregulation of BMP4 in the chronic phase of colitis. Importantly, connective tissue growth factor and noggin expression were elevated in the acute stage and significantly decreased upon BMP7 therapy. BMP receptor I expression was unchanged, whereas BMP receptor II was decreased at day 2 and increased at days 14 and 30 of TNBS inflammation. However, an opposite pattern of expression following BMP7 therapy has been observed. BMP7 increased the expression of BR-Smad including Smad3 and Smad4. Inhibitory Smads were increased in colitis and significantly decreased following BMP7 therapy at later stages of the disease. We suggest that BMP signaling was altered during TNBS-induced colitis and was recovered with BMP7 administration, suggesting that IBD is a reversible process.

Shape, structural properties, and cortical stability along the femoral neck: a study using clinical QCT

This study used clinical quantitative computer tomography (QCT) to obtain detailed estimates of the structural properties and cortical dimensions of cross-sections (CSs) along the femoral neck (FN). The computer tomography scans of both proximal femora of 27 postmenopausal women (mean age 81, range 65-86yr) with osteoporosis were processed and analyzed. The cross-sectional shape, cortical and trabecular bone area, and section moduli under different fall directions were calculated. Furthermore, each CS was divided into 8 sectors and cortical thickness and buckling ratio were estimated for each octant. The cross-sectional shape was found to be increasingly elliptic and both tensile and compressive section moduli increased significantly (by a factor of up to 1.8) from the proximal to distal half of the FN. The section modulus was dependent on the fall direction; it was maximal when falling 20 degrees anterior and at its lowest (reduced by as much as 37%) when falling 50 degrees posterior on the greater trochanter. The cortex was significantly thinner (< or =1mm) in the anterior, superoanterior, superior, superoposterior, and posterior octants than the inferomedial aspect of the FN. In conclusion, multiple site measurements are required for a comprehensive assessment of FN structural properties, which can be studied based on clinical QCT.

Tributaries of the human and canine coronary sinus

The coronary sinus is an anatomic landmark and conduit for many diagnostic and therapeutic procedures. We studied 40 human and 40 canine coronary sinuses of the heart in order to ascertain various functional anatomic features of the coronary sinus and its tributaries. We performed a comparative analysis of human and canine cardiac veins. We also studied the formation, tributaries, length, diameter and the ostium of the coronary sinus. The tributaries of the coronary sinus were highly variable in human and dog. The main and constantly present tributaries of both the human and canine coronary sinus were the great and the middle cardiac veins. We also found a rare case of a small cardiac vein connecting two cardiac venous systems--the coronary sinus and its tributaries and the anterior cardiac veins. In two cases we found a common trunk of the small cardiac vein and middle cardiac vein which opened into the coronary sinus. An intramyocardial course of the anterior interventricular vein was found in 2 cases and in 1 case the vein curved twice around the anterior interventricular branch of the left coronary artery. The Thebesian and Vieussens valves and ostial valves of other cardiac veins were also found.

How activity of inflammatory bowel disease influences bone loss

Bone loss is a common problem for individuals with inflammatory bowel disease (IBD). The aim of our study was to assess bone mineral density (BMD) in patients with IBD and to investigate the role of corticosteroid (CS) use and duration and activity of disease on BMD. Ninety-two patients (56 men and 36 women) with IBD, of whom 32 had ulcerative colitis (UC) and 60 had Crohn's disease (CD), underwent clinical assessment. Lumbar and femoral neck BMDs were measured by dual-energy X-ray absorptiometry. Osteopenia was observed in 14 patients (43%) with UC and in 24 patients (40%) with CD (p=0.187). Four patients (12%) with UC and 7 patients (11%) with CD had osteoporosis (p=0.308). Femoral BMD decreased in patients with long duration of CS use and correlated inversely with disease activity. Multiple regression analysis of BMD showed that statistically significant risk factors were duration of active disease and body mass index as well. Based on our results, it is necessary to take into account the risk of decreased BMD in patients with IBD. It is most important to achieve disease remission as soon as possible in addition to nutritional support.

Study of the healing process after transplantation of pasteurized bone grafts in rabbits

Different bone allografts (pasteurized, autoclaved, and frozen) were compared based on their osteoinductive properties. Our primary purpose was to examine the biologic qualities of pasteurized allografts, as pasteurization inactivates most viruses transmitted by transplantation. Frozen, pasteurized, and autoclaved allografts were packed into a standard defect of rabbit ulna. The animals were sacrificed at 2 and 4 weeks after surgery. The parts of bones with experimental defects were explored en bloc, and a roentgenogram was carried out. Ulna bone samples were then embedded in methyl-methacrylate. Roentgenograms showed that after 2 weeks, calluses were well-formed, but irregular in shape in all 3 types of allografts. After 4 weeks, the calluses were regular in shape in all but the autoclaved grafts. After 2 weeks, the healing processes had begun in the frozen and pasteurized grafts, with the reaching approximately the same stage, while in the autoclaved grafts these processes were not seen and the bone particles were surrounded by connective tissue without any changes. After 4 weeks, osteoinductive processes were very strong, with the first signs of complete bone remodeling at the bone edges of the defect in pasteurized and frozen allografts. The osteoinductive values of these 2 types were very high and similar. Autoclaved allografts, on the other hand, had very low osteoinductive values, as they were still at the very beginning of the healing process. Histomorphometric analysis revealed a significant difference in both newly formed osteoid thickness and osteoblast number per microm of bone surface in all experimental groups (P < 0.005). Values of osteoid thickness and osteoblast number were significantly higher in both frozen and pasteurized grafts when compared with the autoclaved ones (P < 0.005). Osteogenic properties of pasteurized bone allografts were preserved, and the allografts have been gradually replaced with newly formed bone. As such, pasteurized bone grafts from a bone bank have approximately the same biologic validity as frozen grafts, while autoclaved grafts impair bone healing.

Expression of receptor activator of nuclear factor-kappa B ligand in leukocytes during acute kidney rejection after transplantation in rats

BACKGROUND

Acute cellular rejection of the transplanted kidney is an important cause of impaired graft function. One of the basic characteristics of acute cellular rejection according to the latest Banff classification of renal allograft pathology is the presence of a large number of T lymphocytes in the allografted tissue. Osteoprotegerin, receptor activator of nuclear factor-kappa B (RANK) and RANK ligand (RANKL), three relatively novel members of the tumor necrosis factor superfamily, have crucial roles not only in physiologic and pathologic bone metabolism but also in immunologic processes. The aim of our study was to determine the expression of RANKL and RANK by T lymphocytes and macrophages in acute cellular kidney allograft rejection in rats.

METHODS

The study included 15 male Wistar rats of 3 months old and 250-300 g as recipients and 15 male DA rats donors of 3 months old; and weight 250-300 g. When animals were sacrificed at 3 weeks to extract the transplanted kidney for pathohistologic analysis and immunoflorescence. all samples showed acute cellular rejection. Kidney sections were examined by dual-labeled immunofluorescence to detect CD4, CD8, or CD68 (red) and RANK or RANKL (green) with coexpressing cells as orange.

RESULTS

RANKL-positive expression colocalized with CD4(+) and CD8(+) T lymphocytes in acutely rejected kidney tissue. There was no association between CD4(+) and CD8(+) T cells with RANK expression, which was evident by infiltrating CD68-positive macrophages in the kidney tissue interstitium.

CONCLUSION

RANK and RANKL were expressed by T lymphocytes and macrophages in acute cellular kidney rejection after transplantation in rats.

Immunoregulating effects of peptidoglycan monomer linked with zinc in adult mice

Since it is well known that both zinc ions and bacterial immunostimulants influence the function of the immune system, in the present study we investigated the immunomodulating activity of a new analog of peptidoglycan monomer (PGM), in which the basic molecule was linked to zinc (PGM-Zn). Its effects in BALB/c mice, aged 10-12 months, were compared with the effects of equimolar doses of PGM and ZnCl2. The treatment lasted 26 days (one i.p. injection every fifth day). The results showed that PGM-Zn may markedly enhance antibody production to sheep red blood cells, as well as spontaneous and concanavalin A (ConA)-induced blastogenesis. The generation of plaque-forming cells in individual mouse was positively correlated with the expression of class II antigens in the liver and negatively correlated with the total quantity of hepatic proteins. PGM-Zn also induced the appearance of peritoneal macrophages, which in cocultures with syngeneic splenocytes were less able to enhance the spontaneous, and particularly the ConA-induced blastic transformation. The enhancing activities of PGM-Zn were in some respects more closely correlated with the action of PGM, whereas the induction of suppressive macrophages resembled more the activity of ZnCl2. The data emphasize that PGM-Zn may both stimulate and inhibit immunoregulative pathways by mechanisms which are not identical to those of PGM or ZnCl2.

Therapeutic Potential of BMP7 in the Treatment of Osteoporosis Caused by the Interaction between Inflammation and Corticosteroids in Inflammatory Bowel Disease

Individuals with inflammatory bowel disease (IBD) have an increased risk of bone impairment, which is a process controlled by the RANKL/RANK/OPG system, mostly due to chronic inflammation and corticosteroid treatment. Bone morphogenic protein 7 (BMP7) has a complex role in maintaining inflammation and bone remodeling but little is known about its anti-inflammatory potential in chronic colitis. We investigated the effect of systemically administered BMP7 and corticosteroids on the severity of inflammation, macrophage differentiation, and bone regeneration in a chronic IBD model.

METHODS

Chronic colitis was induced in male Sprague Dawley rats via weekly administration of 2,4,6-trinitrobenzenesulfonic acid over 21 days following BMP7 or corticosteroid treatment for five days. The levels of serum and colon tissue inflammatory cytokines, RANKL/OPG system, as well as markers of macrophage polarization, were detected using RT-PCR, ELISA, or immunohistochemistry. Long bone and spine analyses were performed using microcomputed tomography (micro-CT).

RESULTS

The administration of BMP7 reduced the adverse effects of colitis and led to elevated OPG and RANK in the colon with a simultaneous decrease in TNF-α and an increase in IL-10 and TGF-β. Decreased expression of the M2 macrophage marker CD163 was found in the BMP7-treated rats compared with the colitis group, whereas the number of M1 marker iNOS-positive cells did not differ between the groups. As a result of the BMP7 treatment, morphometric parameters of trabecular bone increased, and increased trabecular separation noted in the colitis group did not appear.

CONCLUSIONS

We showed that BMP7 suppressed the inflammatory response in chronic colitis, mainly by shifting the cytokine balance and by triggering alterations in the RANKL/OPG system rather than through a macrophage polarization imbalance. In addition, considering the demonstrated effect of BMP7 on bone morphology and structure, it can be suggested that BMP7 plays a role in the managing of osteoporosis in chronic colitis, and thus, its therapeutic potential in the treatment of IBD should be further evaluated.

Expression of the BMP-2, -4 and -7 and their antagonists gremlin, chordin, noggin and follistatin during ectopic osteogenesis

Molecular network of the osteogenic BMPs and extracellular inhibitors maintains homeostasis of the skeletal tissues. It is important to determine relationship between BMP-2, -4 and -7 and their inhibitors: gremlin, follistatin, chordin and noggin, during normal osteogenesis. To determine their expression pattern we conducted investigation by inducing ectopic bone formation in rats. The results shown that levels of the BMP-2 and BMP-4 expression in chondrocytes are similar to noggin and follistatin. The latter BMPs and inhibitors have increased levels of the expression at day 14th of the osteogenesis, which suggests their important roles in early phases of the chondrogenesis. Gremlin and chordin have shown increased levels of expression in late phase of chondrogenesis, which suggests their important role in regulation of the osteogenesis initiation. In this study, BMPs and inhibitors have the highest levels of the expression at 21st day in the osteocytes, which suggests their strong interactions in osteogenesis.

How to create a faculty development program that transforms medical education according to actual institutional needs: evidence-based approach and experience at the University of Rijeka, Faculty of Medicine, Croatia

Aim

Although previous studies demonstrated short, medium and long-term effectiveness of faculty development programs (FDP) for medical teachers, there is a lack of studies describing the methodology for creating a sustainable comprehensive FDP in medical education. We present the methodology for creating the "Modern and Practical Medical Education (MPME)," a comprehensive four-month educational FDP tailored to actual institutional needs, and the initial results of its implementation and transformation of medical education at the University of Rijeka, Faculty of Medicine, Croatia (EU).

Materials and methods

We conducted a multi-phase mixed-method cross-sectional study from July 2021 to June 2024 consisting of three steps: (1) construction of MPME FDP basic structure according to local/national priorities/specificities, literature and expertise, (2) a 360-degree current state analysis for adaptation of basic structure to actual institutional needs, and (3) analysis of the FDP education effectiveness. Step 2 included syllabi analyses and group interviews with 65 teachers' at 8 departments (qualitative), as well as the analysis of medical students' perspective using the "Medical students' questionnaire" on 236 participants (quantitative), and 23 interviews with 8 participants using the "Medical students' focus group" (qualitative). Step 3 included the quantitative analysis of 40 medical teachers' self-assessments for 30 teachers' competencies before and after MPME education using the "MPME questionnaire," and qualitative analysis of measurable program outcomes.

Results

The MPME FDP consists of three major modules with seven courses, and is based on a tripartite flipped classroom model. The results of qualitative and quantitative 360-degree analysis identified common weak spots in teachers' competencies, which were used for program development. Program effectiveness was demonstrated through a highly significant change in the self-assessment for all 30 teachers' competencies before and after education (p < 0.001), and numerous measurable educational outcomes.

Conclusion

The creation of a comprehensive and sustainable FDP in medical education should be based on a three-step quantitative and qualitative process that includes the 360-degree analysis of actual institutional needs, and the effectiveness of the program education. This methodology has a highly significant positive effect on teachers' competencies at the individual level, and creation of educational projects that transform medical education at the institutional level.

[Rehabilitation approaches in patients after percutaneous lumbar discectomy]

The lumbar ache syndrome is more and more getting sign of a social disease because of its rate. Beside the conservative treatment very often the operative treatment is used too. Except the classical discectomy, a percutaneous lumbar discectomy had been used since the last year. In the work we gave the basic anatomical characteristics of the spiral column, stages of intervertebral disk dislocations and general characteristics of the acute ache syndrome. According to Aesculaps prospect we described the operating technique of percutaneous lumbar discectomy as well as the rehabilitation treatment of classical and percutaneous lumbar discectomy.

Odnos lateralnog interkondilarnog grebena i hvatišta prednjeg križnog ligamenta

Cilj: Anatomska tehnika rekonstrukcije predstavlja zlatni standard pri operacijskom liječenju lezija prednjeg križnog ligamenta. Kod postavljanja femoralnog tunela glavni orijentir predstavlja lateralni interkondilarni greben. Greben se nalazi uz prednji rub hvatišta ligamenta i tuneli se postavljaju ispod njega, u centar hvatišta ligamenta. Cilj ove studije je opisati položaj grebena u odnosu na intaktno femoralno hvatište. Materijali i metode: U studiji je korišteno 10 svježe smrznutih kadaveričnih zglobova koljena. Nakon što je uklonjen medijalni kondil femura, vizualno i uz palpaciju analizirano je područje femoralnog hvatišta ligamenta, i to najprije uz očuvan bataljak prednjeg križnog ligamenta, a zatim nakon uklanjanja čitavog hvatišta. Rezultati: Uz održani ligament, u 70 % preparata niti jedan dio lateralnog interkondilarnog grebena nije bio vidljiv izvan hvatišta. U 20 % preparata greben je bio vidljiv samo iznad posterolateralnog snopa prednjeg križnog ligamenta. Nakon što smo odstranili sva vlakna hvatišta prednjeg križnog ligamenta, u jednom preparatu nismo sa sigurnošću mogli odrediti postojanje grebena. Zaključak: U 90 % ispitivanih preparata lateralni interkondilarni greben bio je unutar hvatišta prednjeg križnog ligamenta. Navedeno bi trebalo uzeti u obzir prilikom anatomske rekonstrukcije ovog ligamenta.

Organizacija stručne prakse studenata medicine u Republici Hrvatskoj

Dobro organizirana stručna praksa i mentorski sustav ključni su za obuku budućih liječnika. Cilj stručne prakse je omogućiti studentima ne samo da stečeno teorijsko znanje upotpune s praktičnim vještinama u realnom okruženju nego i razvoj komunikacijskih vještina i etičnosti u kontaktu sa bolesnicima, suradnicima i ostalim dionicima u sustavu zdravstvene skrbi. Programi stručne prakse studenta medicine na studijskim programima u Republici Hrvatskoj omogućavaju studentima medicine stjecanje praktičnog iskustva i poboljšavanje praktičnih kliničkih vještina. Praksa se provodi na sustavan i odgovoran način koji omogućava postizanje predviđenih ishoda učenja. Sustav praćenja i ocjenjivanja kvalitete održavanja stručne prakse treba uključivati evaluaciju od strane studenata i mentora kako bi se osiguralo da se postižu zadani obrazovni ciljevi. Velika je potreba i za ujednačenim kriterijima i programom edukacije mentora usklađenih između medicinskih fakulteta u Republici Hrvatskoj.

Expression of bone morphogenetic proteins, cartilage-derived morphogenetic proteins and related receptors in normal and osteoarthritic human articular cartilage

Newborn and adult articular cartilage expresses bone (BMPs) and cartilage derived morphogenetic proteins (CDMPs). These morphogenetic proteins act over membrane receptors (BMPRs). We examined the expression pattern of BMP-7, BMP-3, CDMP-1, CDMP-2 and their receptors in adult normal and osteoarthritic, articular, knee cartilage. Immunostaining was carried out using polyclonal antibodies. The expression of BMP-7,-3, CDMP-1,-2 was detected in all layers of normal articular cartilage with the strongest expression in chondrocytes of the transitional layer. BMP-7 and CDMPs expression decreased in osteoarthritic articular cartilage whereas BMP-3 expression was absent. BMPR-IA and BMPR-II were strongly expressed in both normal and osteoarthritic articular cartilage. BMPR-IB was not expressed in osteoarthritic (OA) cartilage. BMPs and CDMPs with intact signalling play an important role in articular cartilage homeostasis, preventing cartilage degeneration.

Effects of Type 2 Diabetes Mellitus and Smoking on Changes in Corneal Endothelial Morphology and Cell Density

PURPOSE

The purpose of this study was to compare the corneal endothelial morphology and cell density of diabetic smokers and nonsmokers with 50 to 70 age-matched healthy subjects and to determine whether smoking increases the effects of type 2 diabetes mellitus (DM) on these corneal parameters.

METHODS

This prospective cohort study included 200 patients who were assigned to 4 groups, including smokers with type 2 DM (group 1), nonsmokers with type 2 DM (group 2), healthy smokers (group 3), and healthy nonsmokers (control group, group 4). Noncontact specular microscopy was used to measure central endothelial cell density (ECD), coefficient of variation of cell area, percentage of hexagonal cells, and central corneal pachymetry (CCT).

RESULTS

According to the ECD and CCT values ( P < 0.001 and P = 0.013, respectively), a significant difference was observed between the groups. The mean ECD was lowest in diabetic smokers (1917 ± 399 cells/mm 2 ). Healthy smokers and diabetic smokers had significantly lower ECD compared with the control group ( P = 0.03 and P < 0.001, respectively). Healthy smokers and diabetic smokers had significantly lower ECD compared with diabetic nonsmokers ( P = 0.012 and P < 0.001, respectively). The cornea was significantly thicker in the diabetic smokers than in the control group ( P = 0.013).

CONCLUSIONS

The coexistence of DM and smoking causes a significant decrease in ECD and an increase in CCT. Cigarette smoking is more harmful to corneal endothelial cells than DM alone.

Expression of bone morphogenetic proteins in human metastatic prostate and breast cancer

AIM

To analyze the expression of bone morphogenetic proteins (BMPs) in prostate and breast cancers with established metastasis in bone, where prostate cancer causes osteoblastic metastases, and breast cancer osteolytic metastases.

METHODS

Primary tumor specimens from 20 patients with prostate cancer and 15 with breast cancer were studied for BMP-2/4, -3, -5, -6 and -7 immunohistochemistry. All patients had multiple bone metastases proven by bone scan. We also examined BMPs expression in normal prostate and breast tissues. BMPs expression was compared with clinicopathological and biochemical parameters.

RESULTS

Cytoplasmic BMPs immunostaining was observed in both prostate cancer and normal prostate tissue. Expression of BMP-2/4, -5, -6, and -7 proteins was detected in all normal prostate samples, with the predominance of BMP-2/4 (87.8-/+11.4% positive cells) and BMP-7 (94.6-/+0.9% positive cells). In prostate cancer tissues, we found variable expression of all BMPs. BMP-2/4 (83-/+11.6% positive cells) was predominantly expressed in prostate carcinoma, whereas the expression of BMP-7 (24.3-/+19.2% positive cells) was significantly lower than in the normal prostate. In all breast cancers tissues, we found nuclear staining only for BMP-7. In normal breast tissue, the BMP expression was not detectable. The percent of BMP-7 positive cells in breast cancer (86.4-/+7.3%) was higher than in prostatic cancer. Comparing BMP expression levels and clinicopathological parameters, we did not find statistical difference, except for serum alkaline phosphatase, which was significantly higher in patients with prostate cancer.

CONCLUSION

The expression of BMPs differs between prostate and breast cancer cells. Identifying the BMP proteins in cancers may be useful for monitoring the tumor status with reference to metastases.

Age-related and gender-related differences between human vertebral and iliac crest bone--a histomorphometric study on the population of the Mediterranean Coast of Croatia

In this study, osseous tissue was examined in normal adult population that has inhabited areas by the Croatian Adriatic Sea. The most of such studies have shown that women are prone to lose bone connectedness, while men are predisposed to be a stronger constitution and they start with greater bone mass, though. Bone samples from two different anatomic sites were analyzed. The crista iliaca and the lumbar vertebra represent functionally different organs too. We wanted to consider weather the same age- and gender-related changes affect these two organs due to normal aging. Static histomorphometry was used to quantify involution changes in the trabecular bone. Results showed that involution process more severely affects women than men. Age-related structural changes were more prominent in lumbar vertebra than in iliac crest bone. Severe structural changes in lumbar vertebra could subsequently lead to a dysfunctional and deformed vertebral column. Therefore, iliac crest bone biopsies could hardly explain involution process that affects lumbar spine.