Calcification and bone marrow formation in ureteropelvic junction obstruction

Abnormal deposits of calcium in ischemic and necrotic tissue is a common finding in human pathologic conditions. Calcium is found in 1 to 2 per cent of simple renal cysts and 10 per cent of renal cell carcinomas. Calcification in hydronephrosis secondary to ureteropelvic junction obstruction is rare. No cases of bone marrow arising within a calcified renal mass have been reported.     

Differential growth factor control of bone formation through osteoprogenitor differentiation

The osteogenic factors bone morphogenetic protein (BMP-7), platelet-derived growth factor (PDGF)-BB, and fibroblast growth factor (FGF-2) regulate the recruitment of osteoprogenitor cells and their proliferation and differentiation into mature osteoblasts. However, their mechanisms of action on osteoprogenitor cell growth, differentiation, and bone mineralization remain unclear. Here, we tested the hypothesis that these osteogenic agents were capable of regulating osteoblast differentiation and bone formation in vitro. Normal human bone marrow stromal (HBMS) cells were treated with BMP-7 (40 ng ml(-1)), PDGF-BB (20 ng ml(-1)), FGF-2 (20 ng ml(-1)), or FGF-2 plus BMP-7 for 28 days in a serum-containing medium with 10 mM beta-glycerophosphate and 50 microg ml(-1) ascorbic acid. BMP-7 stimulated a morphological change to cuboidal-shaped cells, increased alkaline phosphatase (ALKP) activity, bone sialoprotein (BSP) gene expression, and alizarin red S positive nodule formation. Hydroxyapatite (HA) crystal deposition in the nodules was demonstrated by Fourier transform infrared (FTIR) spectroscopy only in BMP-7- and dexamethasone (DEX)-treated cells. DEX-treated cells appeared elongated and fibroblast-like compared to BMP-7-treated cells. FGF-2 did not stimulate ALKP, and cell morphology was dystrophic. PDGF-BB had little or no effect on ALKP activity and biomineralization. Alizarin Red S staining of cells and calcium assay indicated that BMP-7, DEX, and FGF-2 enhanced calcium mineral deposition, but FTIR spectroscopic analysis demonstrated no formation of HA similar to human bone in control, PDGF-BB-, and FGF-2-treated samples. Thus, FGF-2 stimulated amorphous octacalcium phosphate mineral deposition that failed to mature into HA. Interestingly, FGF-2 abrogated BMP-7-induced ALKP activity and HA formation. Results demonstrate that BMP-7 was competent as a sole factor in the differentiation of human bone marrow stromal cells to bone-forming osteoblasts confirmed by FTIR examination of mineralized matrix. Other growth factors, PDGF, and FGF-2 were incompetent as sole factors, and FGF-2 inhibited BMP-7-stimulated osteoblast differentiation.     

Plasmin Prevents Dystrophic Calcification After Muscle Injury

Extensive or persistent calcium phosphate deposition within soft tissues after severe traumatic injury or major orthopedic surgery can result in pain and loss of joint function. The pathophysiology of soft tissue calcification, including dystrophic calcification and heterotopic ossification (HO), is poorly understood; consequently, current treatments are suboptimal. Here, we show that plasmin protease activity prevents dystrophic calcification within injured skeletal muscle independent of its canonical fibrinolytic function. After muscle injury, dystrophic calcifications either can be resorbed during the process of tissue healing, persist, or become organized into mature bone (HO). Without sufficient plasmin activity, dystrophic calcifications persist after muscle injury and are sufficient to induce HO. Downregulating the primary inhibitor of plasmin (α2‐antiplasmin) or treating with pyrophosphate analogues prevents dystrophic calcification and subsequent HO in vivo. Because plasmin also supports bone homeostasis and fracture repair, increasing plasmin activity represents the first pharmacologic strategy to prevent soft tissue calcification without adversely affecting systemic bone physiology or concurrent muscle and bone regeneration. © 2016 American Society for Bone and Mineral Research.     

Extramedullary relapse of acute lymphoblastic leukemia in childhood to the prostate

A 6-year-old boy presented with the chief complaints of miction pain and pollakisuria. He had a past history of acute lymphoblastic leukemia (ALL), which subsided in response to chemotherapy at 3 years of age. Ultrasonography revealed urinary retention associated with bilateral hydronephrosis secondary to the prostate enlargement. Computed tomography and magnetic resonance imaging showed no other abnormal finding. Transrectal needle biopsy showed infiltration of leukemic cells in the prostate. Bone marrow puncture and cerebrospinal fluid aspiration revealed no leukemic cells, resulting in a diagnosis of extramedullary relapse of ALL in the prostate. Although he was successfully treated by chemotherapy, irradiation and his voiding function was improved, ALL relapsed in the left testis 1 year later. In spite of left orchiectomy, irradiation and additional chemotherapy, he died of bone marrow relapse and multiple organ failure. Extramedullary relapse of ALL in the prostate is very rare. To our knowledge, our case is the first well-documented report in the published work.     

Dramatic increase in cortical thickness induced by femoral marrow ablation followed by a 3‐month treatment with PTH in rats

We previously reported that following mechanical ablation of the marrow from the midshaft of rat femurs, there is a rapid and abundant but transient growth of bone, and this growth is enhanced and maintained over a 3‐week period by the bone anabolic hormone parathyroid hormone (PTH). Here, we asked whether further treatment with PTH or bisphosphonates can extend the half‐life of the new bone formed in lieu of marrow. We subjected the left femur of rats to mechanical marrow ablation and treated the animals 5 days a week with PTH for 3 weeks (or with vehicle as a control) to replace the marrow by bone. Some rats were euthanized and used as positive controls or treated with vehicle, PTH, or the bisphosphonate alendronate for a further 9 weeks. We subjected both femurs from each rat to soft X‐ray, peripheral quantitative computed tomography (pQCT), micro‐computed tomography (µCT), dynamic histomorphometry analysis, and biomechanical testing. We also determined the concentrations of serum osteocalcin to confirm the efficacy of PTH. Treatment with PTH for 3 months dramatically enhanced endosteal and periosteal bone formation, leading to a 30% increase in cortical thickness. In contrast, alendronate protected the bone that had formed in the femoral marrow cavity after marrow ablation and 3 weeks of treatment with PTH but failed to promote endosteal bone growth or to improve the biomechanical properties of ablated femurs. We further asked whether calcium‐phosphate cements could potentiate the formation of bone after marrow ablation. Marrow cavities from ablated femurs were filled with one of two calcium‐phosphate cements, and rats were treated with PTH or PBS for 84 days. Both cements helped to protect the new bone formed after ablation. To some extent, they promoted the formation of bone after ablation, even in the absence of any anabolic hormone. Our data therefore expand the role of PTH in bone engineering and open new avenues of investigation to the field of regenerative medicine and tissue engineering. Local bone marrow aspiration in conjunction with an anabolic agent, a bisphosphonate, or a calcium‐phosphate cement might provide a new platform for rapid preferential site‐directed bone growth in areas of high bone loss. © 2010 American Society for Bone and Mineral Research     

Calcifying Basal Cell Carcinomas

Background. Dystrophic calcification refers to calcium deposition occurring in association with local tissue injury or abnormality. Little is known about dystrophic calcification occurring in malignant cutaneous neoplasms.
Objective. The purpose of this study was to determine the frequency and pattern of dystrophic calcification occurring in basal cell carcinomas and squamous cell carcinomas.
Methods. Consecutive cases (200) of basal cell carcinoma and squamous cell carcinoma were reviewed for evidence of dystrophic calcification. Histologic subtype, location of calcification, and tumor site were noted.
Results. Of 200 basal cell carcinomas, 41 (21%) showed evidence of dystrophic calcification, compared with 6 (3%) squamous cell carcinomas. Calcifying basal cell carcinomas were more likely to have a more aggressive histologic subtype and to be located on the trunk.
Conclusion. Skin calcium binding protein may be responsible for the calcium deposition and account for the discrepancy seen between the frequency of calcification occurring in basal cell carcinomas and squamous cell carcinomas. As with other tumors with follicular differentiation, calcium deposits were located in keratin-filled cysts. This pattern of dystrophic calcification may be a marker of follicular differentiation.     

Amelioration of anemia after kidney transplantation in severe secondary oxalosis

INTRODUCTION: In small bowel disease such as M. Crohn, the intestinal absorption of oxalate is increased. Severe calcium oxalate deposition in multiple organs as consequence of enteric hyperoxaluria may lead to severe organ dysfunction and chronic renal failure. The management of hemodialyzed patients with short bowel syndrome may be associated with vascular access problems and oxalate infiltration of the bone marrow leading to pancytopenia. Although the risk of recurrence of the disease is very high after renal transplantation, it may be the ultimate therapeutic alternative in secondary hyperoxaluria. CASE: Here, we report a patient with enteric oxalosis due to Crohn's disease. He developed end-stage renal disease, erythropoietin-resistant anemia, oxalate infiltration of the bone marrow and severe vascular access problems. Following high-urgency kidney transplantation, daily hemodiafiltration of 3 hours was performed for 2 weeks to increase oxalate clearance. Despite tubular and interstitial deposition of oxalate in the renal transplant, the patient did not require further hemodialysis and the hematocrit levels normalized. DISCUSSION: Early treatment of hyperoxaluria due to short bowel syndrome is essential to prevent renal impairment. Declining renal function leads to a further increase in oxalate accumulation and consecutive oxalate deposition in the bone marrow or in the vascular wall. If alternative treatments such as special diet or daily hemodialysis are insufficient, kidney transplantation may be a therapeutic alternative in severe cases of enteric oxalosis despite a possible recurrence of the disease.     

Bone matrix and marrow versus cancellous bone in rabbit radial defects

Implants of demineralized bone matrix induce new bone formation. In order to estimate the possible clinical usefulness of this phenomenon, autologous cancellous bone grafts were compared with composite grafts of bone matrix and marrow. Cancellous bone from the tuber ischii of the rabbit was transplanted to a preformed radial defect in the same animal. On the opposite side, a similar defect was filled with a mixture of either allogenous or autogenous bone-matrix particles and autogenous bone marrow. After 25 days, calcium 45 was injected intravenously. Three days later the animals were killed. Standardized segments of the rabbit's forearms, containing the middle of the defect, were cut out, ashed, and analyzed for 45Ca activity. No side difference in 45Ca deposition was found. The callus ash weight of the allogenous matrix-transplanted side was approximately 60% of that of the cancellous bone side. This side difference of ash weights corresponds to the estimated initial mineral content of the cancellous graft. Nontransplanted defects had very low ash weight and 45Ca activity. Thus, in the rabbit, composite grafts of bone matrix and marrow produce a bone yield comparable to that of cancellous bone.     

Osteogenesis in cranial defects and diffusion chambers: Comparison in rabbits of bone matrix, marrow, and collagen implants

In rabbits, we compared calcification and bone formation by bone marrow, acid-demineralized bone matrix and glutaraldehyde-cross-linked Type I collagen implanted in intramuscular diffusion chambers or in trephine skull defects. The rabbits were killed 4 weeks postimplantation and calcification and osteogenesis were evaluated radiographically and histologically, and by calcium and alkaline phosphatase assays. Bone marrow produced bone and fibrous tissue within the chambers and had high alkaline phosphatase levels. Bone matrix in chambers with intact filters failed to induce bone formation within and outside the chambers, while glutaraldehyde-cross-linked collagen produced only scant calcific deposits following implantation in either diffusion chambers or skull defects. Central areas of skull defects implanted with bone marrow were partially repaired with new bone and had high calcium and alkaline phosphatase levels, but not as high as defects implanted with demineralized bone matrix.     

Osteogenesis in cranial defects and diffusion chambers. Comparison in rabbits of bone matrix, marrow, and collagen implants

In rabbits, we compared calcification and bone formation by bone marrow, acid-demineralized bone matrix and glutaraldehyde-cross-linked Type I collagen implanted in intramuscular diffusion chambers or in trephine skull defects. The rabbits were killed 4 weeks postimplantation and calcification and osteogenesis were evaluated radiographically and histologically, and by calcium and alkaline phosphatase assays. Bone marrow produced bone and fibrous tissue within the chambers and had high alkaline phosphatase levels. Bone matrix in chambers with intact filters failed to induce bone formation within and outside the chambers, while glutaraldehyde-cross-linked collagen produced only scant calcific deposits following implantation in either diffusion chambers or skull defects. Central areas of skull defects implanted with bone marrow were partially repaired with new bone and had high calcium and alkaline phosphatase levels, but not as high as defects implanted with demineralized bone matrix.     

The effect of decalcified bone matrix on the osteogenic potential of bone marrow

Rabbit bone marrow cells were cultured in diffusion chambers with or without decalcified bone matrix. The chambers were assayed after 28 days for alkaline phosphatase activity, deoxyribonucleic acid (DNA), calcium, and phosphorus contents. Morphologically, marrow cells incubated with or without matrix differentiated to form bone and cartilage. With bone matrix, the calcium and phosphorus contents of chambers were significantly higher than control chambers. Alkaline phosphatase activity and DNA content were not influenced by inclusion of bone matrix. These results indicate that bone matrix constituents exert a stimulatory effect on bone formation from marrow cells. This osteogenic stimulation could be due to the influence of an osteoinductive factor and/or to stimulation of osteoprogenitor cells known to be present in the marrow.     

Osteogenesis in cranial defects and diffusion chambers: Comparison in rabbits of bone matrix,marrow, and collagen implants

In rabbits, we compared calcification and bone formation by bone marrow, acid-demineralized bone matrix and glutaraldehyde-cross-linked Type I collagen implanted in intramuscular diffusion chambers or in trephine skull defects. The rabbits were killed 4 weeks postimplantation and calcification and osteogenesis were evaluated radiographically and histologically, and by calcium and alkaline phosphatase assays. Bone marrow produced bone and fibrous tissue within the chambers and had high alkaline phosphatase levels. Bone matrix in chambers with intact filters failed to induce bone formation within and outside the chambers, while glutaraldehyde-cross-linked collagen produced only scant calcific deposits following implantation in either diffusion chambers or skull defects. Central areas of skull defects implanted with bone marrow were partially repaired with new bone and had high calcium and alkaline phosphatase levels, but not as high as defects implanted with demineralized bone matrix.     

经皮自体骨髓移植在骨缺损瘢痕组织内成骨作用的实验研究

目的 观察经皮自体骨髓移植在骨缺损瘢痕组织内的成骨作用。方法 选健康家兔１８只，建立双侧桡骨中段骨及骨膜缺损１ｃｍ模型，两骨断端髓腔用骨蜡封闭。６周后，实验侧（右）桡骨骨缺损区经皮注射自体红骨髓２ｍｌ，对照侧（左）桡骨骨缺损区注射自身外周血２ｍｌ。于注射前及注射后不同时间内分别行Ｘ线、组织学检查及骨缺损区瘢痕组织内钙磷含量的测定。结果 注射一１周，实验侧Ｘ线显示以骨缺损为中心形成一个密度增高的弧形     

Periosteal osteosarcoma with secondary bone marrow involvement: a case report

Periosteal osteosarcoma is an exceedingly rare type of chondroblastic osteosarcoma, showing a rather good prognosis, and secondary bone marrow involvement is unusual. However, there have been some reports describing periosteal sarcoma involving medullary bone. We encountered a patient, a 38-year-old man, who had a bone surface tumor in the left tibia. An X-ray showed an erosive cortical mass extraosseous portion, located in the diaphysis of the tibia. Other images revealed a thin cortex, periosteal reactions, coarse mineralization in the extraosseous portion, and bone marrow involvement. Grossly, surgical materials showed that the tumor mainly existed at the periosteal portion, only a part of the cortex was destroyed, and there was medullary involvement throughout. Histological examinations showed a predominantly chondroid component with malignant osteoid formation. On the basis of the histological macroscopic and microscopic findings, we made the diagnosis of periosteal osteosarcoma with secondary bone marrow involvement.     

Optimization of bone tissue engineering in goats: a peroperative seeding method using cryopreserved cells and localized bone formation in calcium phosphate scaffolds

BACKGROUND: Bone tissue engineering by combining cultured bone marrow stromal cells with a porous scaffold is a promising alternative for the autologous bone graft. Drawbacks of the technique include the delay necessary for cell culture and the complicated logistics. We investigated methods to bypass these drawbacks. Furthermore, we investigated the localization of bone formation inside the scaffold. METHODS: Bone marrow stromal cells from seven goats were culture expanded and cryopreserved. One week before surgery, some of the cells were thawed, cultured, and seeded on porous calcium phosphate scaffolds. The constructs were cultured for another week until implantation. The remaining cryopreserved cells were thawed just before implantation and peroperatively resuspended in plasma before combining with the scaffold. Scaffolds impregnated with fresh bone marrow, devitalized cultured constructs, and empty scaffolds served as controls. All samples were implanted in the back muscles of the goats for 9 weeks. RESULTS: Histologic examination showed minimal (<1%) bone in the empty and devitalized scaffolds, 4.2 +/- 5.1 bone area percent in the bone marrow samples, and significantly more bone in both the cultured and peroperatively seeded constructs (11.7 +/- 2.5 and 14.0 +/- 2.0%). The peripheral 350 microm of the implants contained significantly less bone. CONCLUSION: Peroperative preparation of osteogenic constructs with cryopreserved cells is feasible. These constructs yield substantially more bone than the scaffolds alone or scaffolds impregnated with fresh bone marrow. Bone deposition is much less on the scaffold periphery.     

Hypertension associated with unilateral hydronephrosis as a complication of Crohn's disease

Obstructive uropathy with hydronephrosis is a well-known complication of Crohn's disease. The treatment for this condition is still controversial. This is the case study of a 14-year-old girl with documented right-sided obstructive uropathy secondary to Crohn's disease associated with renin-mediated hypertension secondary to her obstructive uropathy. The patient had complete resolution of her hypertension following surgery, which involved only resection of the involved bowel without ureterolysis.     

Psoas abscess with osteomyelitis in a patient undergoing long-term hemodialysis.

We describe a 69-year-old male patient on maintenance hemodialysis for 24 years who developed a fatal left psoas abscess with osteomyelitis at the hip joint following acute enterocolitis. He had systemic beta(2)-microglobulin amyloid deposition in colon epithelium and psoas muscle. Cultures from abscess fluid and femoral bone marrow yielded Bacteroides fragilis. To our knowledge, this is the first case on hemodialysis having a psoas abscess following acute gastrointestinal infection. This rare case suggested that a secondary psoas abscess could be one of the occult infections in patients undergoing long-term maintenance hemodialysis.     

Experimental application of calcium phosphate granulate for the substitution of conventional bone transplants (author's transl)]

Autologous spongiosa, a calcium phosphate ceramic and Kiel bone chips were implanted in the tibiae of dogs and compared with respect to tissue compatibility and osteogenetic effect. After the ceramic implants and the autologous spongiosa had been left in the tibial fat marrow for six weeks, bone tissue and bone marrow had formed to the same extent around both materials. Their stimulating effect on osteogenesis was comparable. In contrast to the ceramic material, together with which they had been implanted in active bone marrow, the Kiel bone chips were surrounded by fibrous tissue in addition to bone tissue. All of the three types of implant proved to be tissue compatible. On the whole, the calcium phosphate ceramic was found to be equal to autologous and superior to heterologous spongiosa from a biological point of view. In technical terms the ceramic implant was superior also to the autologous graft.     

Chondrogenesis and osteogenesis of bone marrow-derived cells by bone-inductive factor

Rat bone marrow cells were intraperitoneally implanted within a diffusion chamber with a decalcified bone matrix or a 4 M guanidine hydrochloride extracted matrix (G-res) as control. The chamber was harvested after 28 days and soft X-ray photography, histological examination, determination of alkaline phosphatase activity and calcium content were performed. With the decalcified bone matrix, cartilage and bone formation was observed and both alkaline phosphatase activity and calcium content were significantly higher than those in control chambers. Each chromatographic fraction on Sephacryl S-200 of the 4 M guanidine hydrochloride extract (G-ext) from the decalcified bone matrix was reconstituted with G-res and implanted either subcutaneously or intraperitoneally within a diffusion chamber with marrow cells. Intrachamber or subcutaneous cartilage and bone formation was detected by only one chromatographic fraction. When marrow-derived fibroblast-like cells were implanted intraperitoneally within a diffusion chamber with a decalcified bone matrix, cartilage and bone formation was detected, which was not the case with G-res. These results suggest that a certain factor, probably bone morphogenetic protein, which induces ectopic bone formation, allows marrow cells to differentiate into bone and cartilage tissues and there may exist so-called "inducible osteoprogenitor cells" in the marrow-derived fibroblast-like cell preparation.     

Bone matrix and marrow versus cancellous bone in rabbit radial defects

Summary Implants of demineralized bone matrix induce new bone formation. In order to estimate the possible clinical usefulness of this phenomenon, autologous cancellous bone grafts were compared with composite grafts of bone matrix and marrow. Cancellous bone from the tuber ischii of the rabbit was transplanted to a preformed radial defect in the same animal. On the opposite side, a similar defect was filled with a mixture of either allogenous or autogenous bone-matrix particles and autogenous bone marrow. After 25 days, calcium 45 was injected intravenously. Three days later the animals were killed. Standardized segments of the rabbit's forearms, containing the middle of the defect, were cut out, ashed, and analyzed for ⁴⁵Ca activity. No side difference in ⁴⁵Ca deposition was found. The callus ash weight of the allogenous matrix-transplanted side was approximately 60% of that of the cancellous bone side. This side difference of ash weights corresponds to the estimated initial mineral content of the cancellous graft. Nontransplanted defects had very low ash weight and ⁴⁵Ca activity. Thus, in the rabbit, composite grafts of bone matrix and marrow produce a bone yield comparable to that of cancellous bone.