Activated T lymphocytes suppress osteoclastogenesis by diverting early monocyte/macrophage progenitor lineage commitment towards dendritic cell differentiation through down-regulation of receptor activator of nuclear factor-kappaB and c-Fos

Activated T lymphocytes either stimulate or inhibit osteoclastogenesis from haematopoietic progenitors in different experimental models. To address this controversy, we used several modes of T lymphocyte activation in osteoclast differentiation--mitogen-pulse, anti-CD3/CD28 stimulation and in vivo and in vitro alloactivation. Osteoclast-like cells were generated from non-adherent immature haematopoietic monocyte/macrophage progenitors in murine bone-marrow in the presence of receptor activator of nuclear factor (NF)-kappaB ligand (RANKL) and monocyte-macrophage colony-stimulating factor (M-CSF). All modes of in vivo and in vitro T lymphocyte activation and both CD4(+) and CD8(+) subpopulations produced similar inhibitory effects on osteoclastogenesis paralleled by enhanced dendritic cell (DC) differentiation. Osteoclast-inhibitory effect was associated with T lymphocyte activation and not proliferation, and could be replaced by their culture supernatants. The stage of osteoclast differentiation was crucial for the inhibitory action of activated T lymphocytes on osteoclastogenesis, because the suppressive effect was visible only on early osteoclast progenitors but not on committed osteoclasts. Inhibition was associated specifically with increased granulocyte-macrophage colony-stimulating factor (GM-CSF) expression by the mechanism of progenitor commitment toward lineages other than osteoclast because activated T lymphocytes down-regulated RANK, CD115, c-Fos and calcitonin receptor expression, and increased differentiation towards CD11c-positive DC. An activated T lymphocyte inhibitory role in osteoclastogenesis, confirmed in vitro and in vivo, mediated through GM-CSF release, may be used to counteract activated bone resorption mediated by T lymphocyte-derived cytokines in inflammatory and immune disorders. We also demonstrated the importance of alloactivation in osteoclast differentiation and the ability of cyclosporin A to abrogate T lymphocyte inhibition of osteoclastogenesis, thereby confirming the functional link between alloreaction and bone metabolism.

Expression of neutral glycosphingolipids in cytokine-stimulated human endothelial cells

We compared immunohistochemical distribution of glycosphingolipids globotriosylceramide (GbOse(3)Cer) and globotetraosylceramide (GbOse(4)Cer) with that of E-selectin on human umbilical vein endothelial cells (HUVEC) stimulated with tumor necrosis factor (TNF)-alpha. HUVECs activated by TNF-alpha were characterized by the highest expression of E-selectin and greatest adhesion of HL-60 cells as well compared to stimulation with interleukin-1beta or lipopolysaccharide. HUVECs activated by TNF-alpha also stained intensely with globoside antibodies, especially with the GbOse(3)Cer-directed one, staining being redistributed in a concentration-dependent manner. These results indicate the possible role of GbOse(3)Cer and GbOse(4)Cer in immune effector mechanisms of endothelium such as adhesion.

Alteration of newly induced endochondral bone formation in adult mice without tumour necrosis factor receptor 1

Tumour necrosis factor (TNF)-alpha, a major proinflammatory cytokine, exerts its role on bone cells through two receptors (TNFR1 and TNFR2). TNFR1, but not TNFR2, is expressed by osteoblasts and its function in bone formation in vivo is not fully understood. We compared in vivo new bone formation in TNFR1-deficient (TNFR1(-/-)) mice and wild-type mice, using two models of bone formation: intramembranous ossification following tibial marrow ablation and endochondral ossification induced by bone morphogenetic protein (BMP)-2. Intramembranous osteogenesis in TNFR1(-/-) mice did not differ from the wild-type mice either in histomorphometric parameters or mRNA expression of bone-related markers and inflammatory cytokines. During endochondral osteogenesis, TNFR1(-/-) mice formed more cartilage (at post-implantation day 9), followed by more bone and bone marrow (at day 12). mRNAs for BMP-2, -4 and -7 were increased during the endochondral differentiation sequence in TNFR1(-/-) mice. The expression of receptor activator of NF-kappa B ligand (RANKL) and receptor activator of NF-kappa B (RANK), as assessed by quantitative reverse transcription polymerase chain reaction (RT-PCR), was also increased significantly during endochondral ossification in TNFR1(-/-) mice. In conclusion, signalling through the TNFR1 seems to be a negative regulator of new tissue formation during endochondral but not intramembranous osteogenesis in an adult organism. BMPs and RANKL and its receptor RANK may be involved in the change of local environment in the absence of TNFR1 signalling.

Test of charge conjugation invariance

We report on the first determination of upper limits on the branching ratio (BR) of eta decay to pi0pi0gamma and to pi0pi0pi0gamma. Both decay modes are strictly forbidden by charge conjugation (C) invariance. Using the Crystal Ball multiphoton detector, we obtained BR(eta-->pi0pi0gamma)<5 x 10(-4) at the 90% confidence level, in support of C invariance of isoscalar electromagnetic interactions of the light quarks. We have also measured BR(eta-->pi0pi0pi0gamma)<6 x 10(-5) at the 90% confidence level, in support of C invariance of isovector electromagnetic interactions.

Dynamics of the pi(-)p-->pi(0)pi(0)n reaction for p(pi(-))<750 MeV/c

Data are presented for the reaction pi(-)p-->pi(0)pi(0)n in the range from threshold to p(pi(-))=750 MeV/c. The systematics of the data and multipole analyses are examined for sensitivity to a f(0)(600) ("sigma") meson. A one-pion-exchange mechanism is found to be very weak, or absent. The reaction appears to become dominated by sequential pi(0) decays through the Delta(1232) resonance as the beam momentum increases, along with substantial interference effects from several competing mechanisms.

Persistent cervical intersegmental artery and aortic arch coarctation

A 15-year-old girl presented with upper extremity hypertension and continuous precordial murmur. Arteriography revealed aortic coarctation proximal to the origin of the left subclavian artery. An anomalous artery originated from the aortic arch, between the left common carotid artery and the stenosis. It ascended cranially and filled an angiomatous vascular formation on the left side of the neck. The "angioma" drained into the left subclavian artery. The embryological explanation of the described anomaly is difficult, but probably related to hemodynamic alterations following the prestenotic increase in blood pressure. This may have impaired the obliteration of cervical intersegmental arteries, resulting in the persistence of one of the first three intersegmental arteries as the anomalous branch of the aortic arch. The angiomatous vascular formation in the neck could be the consequence of altered development of anastomoses between the muscular twigs of both vertebral and deep cervical artery. The vessel draining the vascular formation was probably the thyrocervical trunk. Since there were no overt collateral channels or signs of left ventricular hypertrophy by electrocardiography and echocardiography, it seems that the aberrant collateral flow was hemodynamically significant and reduced the afterload on the myocardium. Although the pattern of collateral flow in our case might be considered extremely rare, it is important in preoperative planning and interpretation of imaging studies.

Ganglioside expression in tissues of mice lacking beta2-microglobulin

This study presents a comparative analysis of gangliosides from lymphoid (spleen and thymus) and other (brain, liver, lungs and muscle) tissues of C57BL/6 mice lacking the gene for beta2-microglobulin (beta2M), a constitutive component of the MHC class I molecule. Ganglioside fractions in the tissues of mice homozygous (beta2M-/-) and heterozygous (beta2M-/+) for the gene deletion were determined by high performance thin-layer chromatography (HPTLC), followed by immunostaining with specific polyclonal antibodies. Ubiquitous gangliosides GM3(Neu5Ac) and GM3(Neu5Gc) were the dominant gangliosides in the lungs of the control beta2M-/+ mice, whereas the homozygous knockout mice had substantially decreased expression of these structures. The lungs of the beta2M-/- mice also had reduced expression of T-lymphocyte-specific GM1b-type gangliosides (GM1b and GalNAc-GM1b). beta2M-deficient mice also had more GM1a and GD1a gangliosides in the liver, and several neolacto-series gangliosides were increased in the brain and lungs. This study provides in vivo evidence that the beta2M molecule can influence the acquisition of a distinct ganglioside assembly in different mouse organs, implicating its non-immunological functions.

Properties of the Lambda(1670)(1-)/2 resonance

Recently the Crystal Ball Collaboration measured precise new data for the near-threshold reaction K(-)p-->etaLambda, which is dominated by formation of the Lambda(1670)1 / 2(-). In this Letter, we present results of a unitary, multichannel analysis that incorporates the new Crystal Ball data. For our preferred fit, we obtain mass M = 1673+/-2 MeV, width Gamma = 23+/-6 MeV, and elasticity x = 0.37+/-0.07. This elasticity is significantly larger than previously recognized. Resonance parameters of our preferred fit are in striking agreement with the quark-model predictions of Koniuk and Isgur.

Determination of the quadratic slope parameter in eta-->3pi(0) decay

We have determined the quadratic slope parameter alpha for eta-->3pi(0) to be alpha = -0.031(4) from a 99% pure sample of 10(6)eta-->3pi(0) decays produced in the reaction pi(-)p-->n(eta) close to the eta threshold using the Crystal Ball detector at the AGS. The result is four times more precise than the present world data and disagrees with current chiral perturbation theory calculations by about four standard deviations.

Weekly quizzes in extended-matching format as a means of monitoring students' progress in gross anatomy

We compared weekly quizzes in extended-matching format with multiple-choice questions and oral examinations as means of monitoring students' progress in gross anatomy. Students' performance on 19 weekly oral examinations or 10-question quizzes based on extended-matching or multiple-choice formats were correlated with their success on 3 interim examinations and the final comprehensive examination. The Kuder-Richardson formula 20, an estimate of precision of the test, was 0.64 for extended-matching quizzes. Students' performance on interim examinations did not differ significantly. There was a significant correlation between students' mean scores on weekly quizzes and mean scores on interim examinations in both the extended-matching (r = 0.516) and multiple-choice group (r = 0.823). The mean grades (ranging from 2 to 5) on the final exam, based on understanding of anatomical concepts and their application in clinical practice, were significantly higher in extended-matching group (4.8) than in the multiple-choice (4.1) and orally examined groups (3.9) (p < 0.05). We conclude that extended-matching quizzes were at least as effective as multiple-choice quizzes and oral examinations and may be better for acquiring synthetic understanding of anatomical concepts especially in combination with other means of knowledge assessment. We recommend them as a reliable and objective means of monitoring students' performance during a gross anatomy course.

Cellular and molecular interactions between immune system and bone

Functional interdependence between immune and bone systems is reflected in a number of regulatory molecules acting on the cells of both systems and common precursors for bone and immune cells. Therefore, the disturbances of the immune system may affect bone metabolism, and vice versa. This review addresses the roles of two major immune cell populations, T and B lymphocytes, in the regulation of bone metabolism. Experimental models and human diseases demonstrated that T lymphocytes may produce many bone cell regulatory cytokines, including two essential stimulators of osteoclastogenesis: receptor for activation of nuclear factor kappa b (NF-kappa B) (RANK) ligand (RANKL) and macrophage colony-stimulating factor. The effect of T lymphocytes on osteoclastogenesis may be both stimulatory and inhibitory, and depends on the activation stage and pattern of cytokine production. We showed that acute removal of T lymphocytes stimulated osteoclast differentiation in vitro and enhanced new cartilage and bone formation at non-osseous sites in vivo. B lymphocytes may be even more closely related to bone cells, as B lymphopoiesis requires an intimate contact with osteoblastic/stromal cells, and estrogens, powerful regulators of bone mass, are also involved in the differentiation of the B lymphocyte lineage. Also, B lymphocyte progenitors may give rise to functional osteoclasts. Both B and T lymphocytes may act through the RANKL/RANK/osteoprotegerin cytokine system, which has been independently discovered within immune and bone systems. These cytokines have crucial roles in the development and function of osteoclasts, dendritic cells, and T and B lymphocytes, as well as in the thymus and lymph node organogenesis. The cytokines produced by immune cells may affect bone cell function and vice versa, but the full complexity of these interactions awaits further investigation.

Good editorial practice: editors as educators

There may be valuable research going on in the developing and financially less-privileged countries, but it usually does not reach international visibility, in spite of a large number of scientific journals in these countries. Such journals are not only invisible but, by perpetuating a vicious circle of inadequacy, may be directly damaging to the local science and research culture. We call for an international action to help journal editors in less privileged countries. International associations of editors may be leaders of these activities by defining, promoting, and perhaps controlling good editorial practice, as a main criterion for international recognition of a journal. However, the editors of small journals have the power and moral obligation to become a stronghold of quality and advancement in their scientific community. Their educational "tools" are editorial integrity and author-friendly policy. Editors can teach the authors study design, statistical analysis, precision, punctuality, research integrity, style and format of writing, and other aspects of scientific communication. The editors of "big", mainstream scientific journals can act as global educators, teaching and providing guidance to editors of small journals. The editors from developed countries as leaders, and editors from less advantageous environments as teachers are the key figures in shaping research communication in less privileged scientific communities.

Measurement of pi(0)pi(0) production in the nuclear medium by pi(-) interactions at 0.408 GeV/c

We report on an investigation of the (pi(-),pi(0)pi(0)) reaction by means of measurements of the pi(0)pi(0) invariant mass distributions from pi(-) interactions on H, D, C, Al, and Cu targets at p(pi(-)) = 0.408 GeV/c. The sharp, strong peak in the pi(+)pi(-) invariant mass near 2m(pi) reported by the CHAOS Collaboration is not seen in our pi(0)pi(0) data. However, we do observe a change in the shape of the pi(0)pi(0) invariant mass spectrum for the different targets, indicating that the pi(0)pi(0) interaction diminishes in the nuclear medium as represented by nuclei D, C, Al, and Cu, compared to hydrogen.

Depletion of CD4 and CD8 T lymphocytes in mice in vivo enhances 1,25-dihydroxyvitamin D3-stimulated osteoclast-like cell formation in vitro by a mechanism that is dependent on prostaglandin synthesis

To investigate the role of T lymphocytes in osteoclastogenesis, we performed in vivo depletion of CD4 and/or CD8 T lymphocyte subsets and evaluated in vitro osteoclast-like cell (OCL) formation. T lymphocyte depletion (TLD) with mAbs was confirmed 24 h later by flow cytometry. OCL formation was stimulated with 1, 25-dihydroxyvitamin D(3) (1,25-(OH)(2)D(3)) in bone marrow and with recombinant mouse (rm) receptor activator of NF-kappaB ligand (RANK-L) and rmM-CSF in bone marrow and spleen cell cultures. OCL formation was up to 2-fold greater in 1,25-(OH)(2)D(3)-stimulated bone marrow cultures from TLD mice than in those from intact mice. In contrast, TLD did not alter OCL formation in bone marrow or spleen cell cultures that were stimulated with rmRANK-L and rmM-CSF. The effects of TLD seemed to be mediated by enhanced PG synthesis, because the PGE(2) concentration in the medium of 1, 25-(OH)(2)D(3)-stimulated bone marrow cultures from TLD mice was 5-fold higher than that in cultures from intact mice, and indomethacin treatment abolished the stimulatory effect of TLD on OCL formation. There was a 2-fold increase in RANK-L expression and an almost complete suppression of osteoprotegerin expression in 1, 25-(OH)(2)D(3)-stimulated bone marrow cultures from TLD mice compared with those from intact mice. Although there was a small (20%) increase in IL-1alpha expression in 1, 25-(OH)(2)D(3)-stimulated bone marrow cultures from TLD mice, TLD in mice lacking type I IL-1R and wild-type mice produced similar effects on OCL formation. Our data demonstrate that TLD up-regulates OCL formation in vitro by increasing PG production, which, in turn, produces reciprocal changes in RANK-L and osteoprotegerin expression. These results suggest that T lymphocytes influence osteoclastogenesis by altering bone marrow stromal cell function.

Association of the truncus bicaroticus, common trunk of the left sub-sclavian and vertebral arteries, and retro-esophageal right subclavian artery. Case report

We present a rare case of combined anomalies of the aortic arch. At its convexity, the arch of aorta gave rise, from right to left, first to the truncus bicaroticus and then to the common trunk of the left subclavian and left vertebral artery. A retro-esophageal right subclavian artery arose from the dorsal aspect of the arch, distally from the common trunk of the left vertebral artery and left subclavian artery. The combination of these anomalies has not been described before and may have important clinical implications.

Croatian Medical Journal at the turn of the millennium

The turn of the millennium coincided with the inclusion of the Croatian Medical Journal into the bibliographic databases MEDLINE (1998), and Current Contents/Clinical Medicine (1999), which greatly increased the number of submitted manuscripts. The increased pressure on the editorial office prompted us to modify the editorial procedure and sharpen our acceptance criteria. At the same time, we extended our author-friendly policy to all for global medicine and (2) medicine in translational and emerging countries. The Editorial Board and the Advisory Board were critical in developing and improving the Journal and setting the highest standards in all aspects of publication, especially in manuscript selection by high-quality peer review. In this editorial, we finally meet the members of the two Boards in person, or rather, in photographs and short biographies.

Ganglioside expression in tissues of mice lacking the tumor necrosis factor receptor 1

This study presents a comparative analysis of gangliosides from lymphoid (spleen and thymus) and other tissues (brain, liver, lung, muscle) of C57BL/6 mice homozygous (-/-) and heterozygous (+/-) for the tumor necrosis factor receptor 1 (TNFRp55). Quantitative and qualitative differences in the expression of the lipid-bound N-acetylneuraminic (Neu5Ac) and N-glycolylneuraminic acid (Neu5Gc) and of various ganglioside biosynthesis pathways were detected between the tissues of the TNFRp55 -/- and the control TNFRp55 +/- mice. Sialic acid profiles showed a strong decrease in the absolute amount of sialic acids (Neu5Ac + Neu5Gc) in the lungs and thymus of homozygous (1.41 and 0.3 ng/mg wet weight, respectively) compared with control heterozygous animals (7.18 and 2.05 ng/mg wet weight, respectively). Considerable differences of Neu5Ac/Neu5Gc ratios in the lungs, muscle, spleen, and thymus were also detected. The gangliosides GM3(Neu5Ac) and GM3(Neu5Gc) were the dominant gangliosides in the lungs of the control animals, whereas the knockout mice almost completely lacked these structures in this organ. Reduced expression of GM1b-type gangliosides (GM1b and GalNAc-GM1b) was also found in the lungs, spleen, and thymus of the TNFRp55 knockout mice. On the other hand, neolacto-series gangliosides were more abundant in the lungs, brain, and muscle of the knockout mice, whereas their expression in the liver, spleen, and thymus was similar in both groups of animals. This study provides in vivo evidence that TNF signaling via the TNFRp55 is involved in the acquisition of a distinct ganglioside assembly in different mouse organs. TNFRp55 signaling seems to be especially important for the activation of the GM1b-type ganglioside biosynthetic pathway that is a unique characteristic of the mouse lymphoid tissues.

Genetic variability of new bone induction in mice

We studied differences in ectopic osteoinduction in eight mouse inbred strains and an outbred strain. Antigen-extracted autolyzed rat bone gelatin was implanted under hind limb muscle fascia of 12-week-old males, and new bone formation was morphologically assessed on serial sections. Four weeks after implantation, less than half of the implants from CBA/J, A/J, BALB/cJ, and C3Hf/Bu mice showed induction of only cartilage. New cartilage was observed in all, and bone and bone marrow in 80% of the implants from AKR/J, C57BL/6J, DBA/2J, and RFM/Rij mice. Volume of the newly formed tissue ranged from 1.3% of the old matrix in A/J strain to 74.6% in DBA/2J strain. Outbred CD1 mice showed only weak cartilage induction. The "good" responders differed among themselves in the volume and type of newly induced tissue: DBA/2J, RFM/Rij, and AKR/J mice had a similar ratio of new bone and cartilage and abundant bone marrow, whereas the predominant newly induced tissue in C57Bl/6J mice was cartilage. The pattern of the expression of BMP-2, -4, and -7, alkaline phosphatase, osteocalcin, interferon-gamma, and granulocyte-macrophage colony-stimulating factor, measured by reverse transcriptase polymerase chain reaction, did not correlate with the type and the quantity of the newly induced tissue. Our results show that adult mice of inbred strains differ not only in the peak bone mass and morphology, but also ability to form new bone after an osteoinductive stimulus. Ectopic osteoinduction may be a useful in vivo model to investigate genetic determinants of endochondral osteogenesis, especially its immunological component.

Sensitivity to metals in 40 patients with failed hip endoprosthesis

Hypersensitivity to metals and tissue reaction around a failed implant were investigated in 40 patients undergoing revision hip arthroplasty. Metal sensitivity was tested using a standard cutaneous patch test. Nine patients were positive for chromium, nickel, cobalt, metal rust or endoprosthesis scrapings, or combinations of these allergens. Patients with positive or negative patch test did not differ in terms of their age, sex, primary diagnosis, number of endoprosthesis revisions, length of implant function, presence of other metal parts around the implant, circulating immunocomplexes, and histological appearance of the tissue around the implant. We conclude that stainless steel endoprostheses may be safely used for repeated revision hip arthroplasty, and that hypersensitivity to metals probably does not play a significant role in the loosening of the endoprosthesis.

Peer review in the Croatian Medical Journal from 1992 to 1996

We analyzed the peer review process in the Croatian Medical Journal (CMJ) from 1992 to 1996 by a retrospective analysis of review forms for 319 manuscripts. The forms asked about manuscript's structure (7 questions), its scientific value (7-item scale), clarity and length, and final recommendation (5-item scale). An international manuscript had at least one author affiliated with a non-Croatian institution. The overall rejection rate of manuscripts was 23.5%. National and international manuscripts had similar rejection rates except for original research manuscripts in clinical sciences (34.7% vs. 18.9%, p=0.046). Out-door peer review was asked for 77.4% of the manuscripts; other manuscripts were commissioned and passed an in-house review. Over the years, the number of international reviewers increased, and that of national reviewers decreased. National reviewers more often did not fill in the review form, and international reviewers more often asked for a major revision. The agreement between reviewers ranged from 34.1% (scientific value) to 90.7% (reference citations). Kappa for inter-rater agreement was poor to fair, without difference between national and international manuscripts. International manuscripts had shorter median review time (from receipt to decision) and publishing time (from acceptance to publication) than national manuscripts: 58 vs. 112 days (p<0.001), and 116 vs. 140 days (p<0.009), respectively. Our analysis shows that peer review can be introduced and sustained in a small journal from the scientific periphery. It can be fair both to national and international manuscripts, although work with the authors of national manuscripts may be needed to improve the quality of data presentation.

Bone turnover in homozygous beta 2-microglobulin knock-out mice does not differ from that of their heterozygous littermates

beta 2-Microglobulin is a constituent of the class I major histocompatibility complex (MHC) molecule and crucial for its normal function in cell recognition. It has also been isolated from bone and shown to regulate bone metabolism and to be altered in various bone diseases. In order to further investigate the role of the immune system in bone metabolism, we studied basic properties of bone physiology in beta 2-microglobulin-deficient mice created by the technique of gene knock-out. Ten week-old male offspring homozygous (non-functional class I MHC molecule) or heterozygous (functional class I MHC molecule) for beta 2-microglobulin knock-out gene did not differ in the following measures of bone turnover: femur length, dry and ash weight and calcium content, serum calcium concentration and alkaline phosphatase activity, total vertebral tissue area, trabecular bone volume, osteid surface, osteoclast surface and mineral apposition rate. These data indicate that the bone turnover in beta 2-microglobulin-deficient mice is appropriate for the stage of their skeletal maturation.

The role of tumor necrosis factor-alpha in the generation of acute phase response and bone loss in rats and talc granulomatosis

BACKGROUND

Trabecular bone loss is the part of acute-phase response (APR) in rats with subcutaneous granulomatous inflammation induced by talc.

EXPERIMENTAL DESIGN

We investigated the possible involvement of inflammatory cytokine, tumor necrosis factor-alpha (TNF-alpha) in the pathogenesis of bone loss and other aspects of APR. Intraperitoneal administration of specific neutralizing antibodies to TNF-alpha or of recombinant cytokine indicated that TNF-alpha was the primary mediator of bone changes, evidence as slower bone elongation rate, bone marrow hyperplasia, and decreased trabecular bone volume and osteoblast number in tibial metaphysis.

RESULTS

Moreover, direct intraosseal administration of anti-TNF-alpha antibody neutralized the effect of inflammation on bone. On the other hand, the serum indices of the APR (decreased zinc and iron concentrations, ACTH and C-reactive protein concentration) were not greatly affected after the administration of anti-TNF antibody, except for the normalization of the hypercupremia and weight loss.

CONCLUSIONS

The data presented in this report demonstrated direct involvement of TNF-alpha in the generation of bone alterations during the development of APR in rats with talc granulomatosis.

Role of 1,25-dihydroxyvitamin D3 in the generation of the acute-phase response in rats with talc-induced granulomatosis

Subcutaneous injection of nonspecific irritants such as magnesium silicate (talc) provokes granulomatous inflammation in the rat. Part of the acute phase response (APR) in these animals is the loss of trabecular bone at sites distant from the site of inflammation. To assess the possible involvement of vitamin D in the bone loss, we studied the development of the acute phase response in vitamin D-deprived rats. The serum APR provoked by subcutaneous inflammation in rachitic rats consisted of hypozincemia, hypercupremia, increased alkaline phosphatase activity and adrenocorticotropic hormone (ACTH) concentration, and was similar to that in control animals except for the absence of hypoferremia. Control rats with talc-induced subcutaneous inflammation also had splenomegaly and decreased total and mononuclear peripheral blood cell counts, while subcutaneous inflammation did not induce spleen changes in rachitic rats. Subcutaneous inflammation induced the loss of trabecular bone and decreased the osteoblastic cell count in tibial metaphyses in control animals. Rachitic rats had abundant osteoid on trabecular surfaces, and the number of osteoblasts and osteoclasts was comparable to that of the controls. Subcutaneous inflammation did not affect any of the bone parameters in rachitic rats. These results indicate that vitamin D plays an important role in the generation of the acute phase response during inflammation, particularly in the induction of spleen and bone cell changes. The discrepancy of the blood on one hand and bone and spleen indices of the APR on the other, indicate that they may be divergent pathways in the generation of the inflammatory response, some of which may be dependent on vitamin D.

Production of leukemia inhibitory factor mRNA and protein by malignant and immortalized bone cells

Leukemia inhibitory factor (LIF) is a recently characterized glycoprotein with complex biologic activities on bone cells. We tested various rodent and human immortalized and malignant bone cell lines and primary osteoblast-enriched cell cultures from fetal rat calvarial digests for expression of LIF mRNA and LIF protein. Both human and rodent immortalized and malignant cells expressed a single 4.4 kb mRNA transcript that hybridized to a human LIF cDNA probe in Northern blots. LIF mRNA was undetectable in unstimulated rodent osteoblast-like cells lines MC3T3-E1 and Py1a. However, treatment with LPS (10 micrograms/ml), TGF-beta (1 ng/ml), TNF-alpha (100 ng/ml) or inhibitors of protein synthesis (cycloheximide, emetine, puromycin, and anisomycin) induced the expression of LIF message in these cells. In contrast, primary osteoblast-enriched cells did not express LIF mRNA in Northern blot assays either constitutively or after treatment with TNF-alpha or cycloheximide. The human osteosarcoma cells lines U-2 OS and Saos-2 constitutively expressed LIF mRNA and did not respond to LPS treatment. However, phorbol myristate acetate (PMA), an activator of protein kinase C, was a potent stimulator of LIF message in Saos-2 but not U-2 OS cells. The effects of PMA (0.5 ng/ml) on LIF mRNA in Saos-2 cells were detectable at 1 h and maximal at 6 h. TNF-alpha (100 ng/ml) and inhibitors of protein synthesis also increased LIF mRNA in both Saos-2 and U-2 OS cells. LIF protein was also detected constitutively in the conditioned medium from both Saos and U-2 OS cells.(ABSTRACT TRUNCATED AT 250 WORDS)

[Histology of bone tissue and histomorphology--report on standardized terminology]

The aim of this paper was to present and describe standardized terminology used in histologic and histomorphometric analysis of bone tissue. Bone tissue is characterized by specific activities which are the result of cell function throughout life. Histologic analysis of bone tissue specimen provides an insight in the features and quality of cellular activities. Histomorphometry is direct measurement and calculation of many parameters which permits quantification of characteristics and dynamics of particular bone tissue function. This method may be applied in diagnostics and monitoring of therapy effects in different metabolic bone disorders.

View of a war from a pathology department: Croatian experience

This report presents an analysis of autopsy records from the Department of Pathology and Forensic Medicine, Osijek General Hospital, in the period from 2 May 1991, when 12 Croatian policemen were killed in an ambush in Borovo Selo and the war against Croatia unofficially began, until 15 January 1992, when the last cease-fire agreement between Croatia and Serbia, sponsored by the United Nations, became effective. During that time, 651 war-related autopsies were performed, constituting 42 per cent of all the deaths recorded in eastern Slavonia for that period. This number presents an 11-fold increase in the number of violent deaths in comparison to the same period of the pre-war year 1989 to 90. Forty-four per cent of all deaths were civilian ones. Explosive wounds were the most frequent cause of death: they accounted for 60 per cent of the civilian and 49 per cent of all the deaths. This fact and the extensive destruction of the cities in eastern Slavonia, including their hospitals, indicate that a principal characteristic of this and many modern wars is sudden and unexpected ground and air attacks on civilian targets.

New bone induction by demineralized bone matrix in immunosuppressed rats

Subcutaneous implantation of demineralized bone matrix (DBM) initiates a sequence of developmental events which culminate in endochondral bone formation. To test the effects of T-cell deficiency on new bone formation, the morphology of DBM-induced bone was examined in rats thymectomized at three weeks of age and in thymectomized or nonthymectomized rats lethally irradiated and reconstituted with syngeneic bone marrow. At 24 days after implantation, bone induction in control rats was appropriate for their age, while thymectomized-irradiated-reconstituted rats and thymectomized rats had significantly more new bone and larger bone marrow space than the controls. In non-thymectomized, irradiated and reconstituted rats, bone induction occurred in only 25% of the animals, compared to 95% in other groups.

Cortisol modulates the actions of interleukin-1 alpha on bone formation, resorption, and prostaglandin production in cultured mouse parietal bones

Previous studies have shown that both interleukin-1 (IL-1) and glucocorticoids inhibit collagen synthesis in bone organ and cell cultures. In this study we examined their interactions in cultured neonatal mouse parietal bones. IL-1 alpha stimulated [3H]thymidine incorporation. Cortisol decreased thymidine incorporation, but did not block the effect of IL-1. Both cortisol and IL-1 alpha decreased the incorporation of [3H]proline into collagenase-digestible protein (CDP) and reduced alpha 1(I)procollagen mRNA levels at 72 h. Noncollagen protein (NCP) labeling was increased by IL-1 and decreased by cortisol. In the presence of cortisol, IL-1 alpha (6 pM) increased CDP as well as NCP labeling. The increase in CDP labeling was paralleled by an increase in alpha 1(I)procollagen mRNA, suggesting a pretranslational site for the cortisol-IL-1 alpha interaction. In the same bones, cortisol consistently blocked IL-1 alpha-stimulated 45Ca release and prostaglandin E2 (PGE2) production. The ability of IL-1 alpha to increase CDP in the presence of cortisol was the same in the presence or absence of indomethacin, an inhibitor of PGE2 synthesis, or aphidicholin (30 microM), an inhibitor of DNA synthesis, indicating that the reversal was neither PG mediated nor dependent on cell proliferation. In conclusion, our results demonstrate that IL-1 inhibits collagen, but not NCP or DNA, synthesis and that cortisol inhibits IL-1 alpha-induced bone resorption and PGE2 production and reverses its inhibitory effect on collagen synthesis in cultured neonatal mouse calvariae.

[The civilian massacre in Dalj on 1 August 1991]

On August the 1st, 1991, Yugoslav Federal Army and Serbian terrorists attacked the village of Dalj, near Osijek in Eastern Slavonia. The civilians took refuge in Osijek and Hungary, but many of them were captured by terrorists. Their fate is still unknown, and the number of missing persons is more than 300. The Federal Army denies the entry to the village and permitted only 25 cadavers to be taken to the Osijek Hospital. Two out of 25 were civilians: P. D., a baker of Albanian origin, and N. T., baker's assistant, a Croat. The decedent N. T. was killed from the back by rifle fire, while the decedent P. D. was first beaten and then executed by two close-range gunshots in the head.

[Civilian massacre near Podravska Slatina, 3 September 1991]

Twenty one civilians, 5 women and 16 men, were found dead in their doorways and yards after Serbian terrorists attacked the village of Cetekovac on 3 September 1991. The age of the decedents ranged from 18 to 91 years. The oldest victims were women (aged 63, 68, 72, 86 and 91). The wounds found on 19 decedents were characteristic of the long-range gunshot wounds, with projectiles fired mostly from the back or/and the side of the body. The autopsy of one decedent (J. B.) revealed that he died from two stabbing wounds and that those were the only wounds inflicted to the body. The body of the decedent (M. S.) was heavily carbonized so that the cause of the death or even whether he was alive when his body was set on fire could not be estimated.

Acute zinc deficiency and trabecular bone loss in rats with talc granulomatosis

Subcutaneous inflammation induced by magnesium silicate (talc) leads to the suppression of bone elongation, osteoblast insufficiency, and subsequent bone loss in rats. Since bone and immunological changes in talc granulomatosis are similar to those observed in zinc deficiency, we investigated the kinetics of zinc tissue distribution and the effects of zinc supplementation on the development of bone loss in rats with talc-induced inflammation. Decrease in serum zinc concentration was observed between 5 and 15 h in rats with talc granulomatosis. It was paralleled by the accumulation of zinc in the liver and rapid disappearance of osteoblasts from the trabecular bone surfaces. However, talc-injected rats supplemented parenterally and orally with zinc sulfate exhibited a decrease in osteoblast trabecular surface comparable to that of unsupplemented rats bearing granulomas despite normalized serum zinc concentrations. Zinc supplementation slightly increased osteoblast trabecular surface in all supplemented groups, but this effect was not significant. We conclude that zinc is the earliest indicator of the acute-phase response in rats with talc granulomatosis. Although zinc appears to be important for the normal function of bone cells, there is no causative relationship between acute zinc deficiency and decreased osteoblast number and activity in rats with talc granulomatosis.

Effects of transforming growth factor-beta and IL-1 alpha on prostaglandin synthesis in serum-deprived osteoblastic cells

We investigated the effects that the combination of IL-1 alpha and transforming growth factor-beta (TGF-beta) had on PGE2 production in a murine clonal osteoblastic cell line MC3T3-E1 and primary rat calvarial osteoblast-like cells. In serum-supplemented medium, IL-1 alpha was a potent stimulator of PGE2 production in MC3T3-E1 cells (50-fold increase with 0.1 ng/ml). TGF-beta (10 ng/ml) had only a small effect alone and no additional effect on IL-1 alpha-induced responses. In serum-deprived MC3T3-E1 cells, PGE2 responses to IL-1 alpha were either absent or markedly reduced. TGF-beta alone had small effects. However, simultaneous addition of TGF-beta with IL-1 alpha to MC3T3-E1 cells partially restored the ability of IL-1 alpha to generate a PGE2 response (10-fold increase in PGE2 with 0.1 ng/ml of both IL-1 alpha and TGF-beta). As with MC3T3-E1 cells, serum-deprived primary fetal rat calvarial osteoblastic cells also did not respond to IL-1 alpha, unless TGF-beta was present in the medium (sixfold increase in PGE2 with 0.1 ng/ml IL-1 alpha and 10 ng/ml TGF-beta). The synergistic effect of TGF-beta and IL-1 alpha was specific for PGE2 responses, because these factors did not synergistically affect cell proliferation, collagen and noncollagen protein synthesis, or alkaline phosphatase activity. The observed synergy was not associated with changes in the steady state cyclooxygenase (PGH synthase) mRNA levels. However, it did correlate with increased release of [3H]arachidonic acid from prelabeled serum-depleted MC3T3-E1 cells. Hence, the synergistic interactions of IL-1 alpha and TGF-beta on PGE2 appear to occur through an increase in the release of arachidonic acid substrate from phospholipid pools. These effects may be important for both normal bone turnover and the responses of bone to inflammatory and immune stimuli.

Effects of transforming growth factor-beta and IL-1 alpha on prostaglandin synthesis in serum-deprived osteoblastic cells

We investigated the effects that the combination of IL-1 alpha and transforming growth factor-beta (TGF-beta) had on PGE2 production in a murine clonal osteoblastic cell line MC3T3-E1 and primary rat calvarial osteoblast-like cells. In serum-supplemented medium, IL-1 alpha was a potent stimulator of PGE2 production in MC3T3-E1 cells (50-fold increase with 0.1 ng/ml). TGF-beta (10 ng/ml) had only a small effect alone and no additional effect on IL-1 alpha-induced responses. In serum-deprived MC3T3-E1 cells, PGE2 responses to IL-1 alpha were either absent or markedly reduced. TGF-beta alone had small effects. However, simultaneous addition of TGF-beta with IL-1 alpha to MC3T3-E1 cells partially restored the ability of IL-1 alpha to generate a PGE2 response (10-fold increase in PGE2 with 0.1 ng/ml of both IL-1 alpha and TGF-beta). As with MC3T3-E1 cells, serum-deprived primary fetal rat calvarial osteoblastic cells also did not respond to IL-1 alpha, unless TGF-beta was present in the medium (sixfold increase in PGE2 with 0.1 ng/ml IL-1 alpha and 10 ng/ml TGF-beta). The synergistic effect of TGF-beta and IL-1 alpha was specific for PGE2 responses, because these factors did not synergistically affect cell proliferation, collagen and noncollagen protein synthesis, or alkaline phosphatase activity. The observed synergy was not associated with changes in the steady state cyclooxygenase (PGH synthase) mRNA levels. However, it did correlate with increased release of [3H]arachidonic acid from prelabeled serum-depleted MC3T3-E1 cells. Hence, the synergistic interactions of IL-1 alpha and TGF-beta on PGE2 appear to occur through an increase in the release of arachidonic acid substrate from phospholipid pools. These effects may be important for both normal bone turnover and the responses of bone to inflammatory and immune stimuli.

Holographic analysis of the human pelvis

Twelve fresh human pelves with preserved lumbar spines, hip joints, and ligaments, were tested by double-exposure and sandwich-hologram interferometry. During physiologic loadings (50-300 N), the pelvis moved as a whole downward and backward. Iliac wings exhibited marked undulation, except for the central part, which showed minor deformations. The sacrum moved downward and rotated forward over an axis 5-9 cm below the promontorium. Removal of the sacroiliac interosseous ligaments eliminated all joint movements and caused a tighter contact between articular surfaces. Removal of the sacrotuberous and sacrospinous ligaments had no influence on the pelvic behavior. The magnitudes of deformations as well as their underlying mineral contents were unequally distributed between the two pelvic sides. These results indicate that the sacroiliac interosseous ligaments are the main determinant of sacral movement. Asymmetric load transmittance to the hip joints might be responsible for the mineral content differences between the pelvic sides.

Cellular and morphological changes in lymphoid organs after a single injection of interleukin 1 alpha in the mouse

We investigated the effects of a single i.v. injection of recombinant human interleukin 1 alpha (IL-1 alpha) on the morphology and the cellularity of several lymphoid organs in normal mice. The injection of 100 U of IL-1 alpha resulted in maximal neutrophilia and leukocytosis at 1 h. By 72 h, the numbers of mononuclears, but not that of polymorphonuclears, returned to baseline levels. Absolute increase in mononuclears was paralleled by relative lymphopenia. Changes in the peripheral blood coincided with rapid decrease in the spleen cellularity and white pulp volume (especially the marginal zone), and an increase in the red pulp volume. Bone marrow cellularity was increased at 1 h, but returned to control levels by 6 h after IL-1 injection. Thymus cell depletion and cortex atrophy were maximal at 6 h and could be observed throughout the experiment. These findings indicate that leukocytosis induced by a single i.v. injection of IL-1 alpha in normal mice is concomitant with a rapid cell depletion of the spleen and thymus. Morphological and cellular changes in lymphoid organs may represent the mobilization of immunocompetent cells during the development of the inflammatory response.

Talc granulomatosis in the rat. Involvement of bone in the acute-phase response

We investigated the dynamics of the acute-phase response (APR) and osteoblast trabecular surface in rats with subcutaneous inflammation provoked by magnesium silicate (talc). The first visible indicator of the APR was a rapid and profound hypozincemia, paralleled by a decrease in metaphyseal trabecular surfaces covered with osteoblasts in long bones. Both the intensity of serum APR and the decrease in osteoblast trabecular surface were directly proportional to the number of granulomas. Alterations in bone metabolism were specific for the inflammation, whereas mild hypozincemia and decrease in mononuclear and increase in polymorphonuclear peripheral white blood cell fractions developed in animals pair-fed with rats bearing two or four granulomas. Rats with talc granulomatosis had high serum ACTH and corticosterone levels, but neither adrenalectomy nor high doses of hydrocortisone could revert bone alterations in talc-injected animals. Glucocorticoids were necessary for the development of hypozincemia and hypercupremia seen in talc granulomatosis, as well as for normal bone metabolism. Inhibition of prostaglandin synthesis had no effect on bone alterations and serum APR in rats bearing talc-induced granulomas. We conclude that the decrease in bone formation constitutes an important aspect of the host acute-phase response in a rat model of talc granulomatosis.

New bone formation in autologous membranous bone transplanted into the anterior abdominal wall

During a gross anatomy dissection, a piece of the calvarial bone was found between aponeuroses of the anterior abdominal wall in an 82-year-old male cadaver. It corresponded closely in size to the calvarial defect after the neurosurgery performed 5 years before death, showing that very little resorption had occurred over the years. Moreover, 13 percent of the transplant was new bone, indicating that membranous bone can, in the long term, induce new bone formation in humans.

Talc granulomatosis in the rat: the relationship between osteoblast insufficiency and adjacent bone marrow hyperplasia

Bone loss in talc granulomatosis is paralleled by hyperplasia of bone marrow in the rat. To test the hypothetical relation between those two phenomena, bone matrix osteoinduction was employed as a model in which bone formation and bone marrow appearance are separated in time. Implantation of demineralized bone matrix to normal rats was followed by three talc injections (one weekly), starting 1 week after matrix implantation. Implants of demineralized bone and [3H]thymidine-labeled tibial metaphyses from talc-injected and normal rats were analyzed histologically and evaluated for alkaline and tartrate-resistant acid phosphatase activity on days 7, 14, 21, and 30 after matrix implantation. Analysis of tibial autoradiographs showed a marked growth arrest and bone marrow hyperplasia in talc-injected rats 7 days after first talc injection. Alkaline phosphatase activity in homogenates of bone implants was low in talc-injected rats on day 14 after implantation. Moreover, histology of the bone implants showed numerical and functional inhibition of osteoblasts on the same day, causing marked growth delay. Bone marrow appeared as late as day 21 after bone matrix implantation. We conclude that hyperplasia of the adjacent bone marrow is not the cause of bone loss in talc granulomatosis, but rather its compensatory consequence.

Immunosuppression induced by talc granulomatosis in the rat

Granulomatosis caused by four subcutaneous talc powder-suspension injections induced strong immunosuppression in rats. The disturbance included reduction of mononuclear white blood cell count in the peripheral blood, atrophy of the thymic cortex, spleen enlargement with predominance of red over the white pulp, increase in the number of lymph node germinal centres and a significant delay of the first-set and second-set allograft rejection. Neither phagocytic function of reticuloendothelial system nor erythrocyte count and humoral immune response were found to be altered. Indomethacin suppression of prostaglandin production did not normalize the allograft rejection dynamics. In contrast, splenectomy completely abolished the immunosuppressive effects of granulomatosis. In splenectomized, talc-treated animals WBC counts were not altered and the rejection of allografts was not delayed. Suppression of immune response to alloantigens was transferred to normal and splenectomized recipients by both serum and spleen cells of talc-injected animals. Also, in a cell mixture-transfer experiment, spleen cells from talc-granulomatosis-bearing donors suppressed the immune response induced by lymph node cells from immune donors in T cell-deficient rats. The inability of serum from splenectomized talc-injected rats to transfer the suppression suggested the crucial role of the spleen in the mechanisms leading to suppression in rats bearing talc-granulomatosis.