Temporary cement tectoplasty: a technique to improve prefabricated hip spacer stability in two-stage surgery for infected hip arthroplasty

This technical note describes an intraoperatively custom-made, antibiotic-loaded bone cement roof, used in conjunction with a prefabricated hip spacer to improve component stability, as part of the first stage of a two-stage procedure for an infected hip implant. This technique was successfully used in seven cases who presented with extensive superior and/or posterio-superior acetabular defect, which created a risk of spacer dislocation. With this technique we were able to avoid any further dislocation in these seven cases. We believe that the technique may reduce postoperative spacer dislocation in cases with extensive acetabular defects, while improving clinical outcomes.

The roles of parathyroid hormone in bone remodeling: prospects for novel therapeutics

The aim of this review is to focus on the roles of PTH in bone remodeling. PTH plays a central role in regulating calcium-phosphate metabolism and its production increases in response to low serum calcium levels. A continue hypersecretion of PTH, as occurs in primary hyperparathyroidism, leads to bone resorption. On the other hand, there is clear evidence of the anabolic properties of PTH.When administered at a low dose and intermittently, this hormone seems to be able to exert positive effects on bone volume and microarchitecture. The effects of PTH are mediated by PTH/PTH-related protein receptor, a G protein that can activate the cAMP-dependent protein kinase (PK)A and calcium-dependent PKC; the activation of PKA account for most of the PTH anabolic action. The anabolic actions of PTH involve direct effects on osteoblasts and indirect effects mediated by activation of skeletal growth factors (IGF-I) and inhibition of growth factor antagonists, such as sclerostin. PTH enhances the number and the activation of osteoblast through 4 pathways: increasing osteoblast proliferation and differentiation, decreasing osteoblast apoptosis and reducing the negative effects of peroxisome proliferator activator (PPAR)γ receptor on osteoblast differentiation. Moreover PTH enhances the Wnt-β catenin pathway, that is central to osteogenesis and bone formation, inhibiting sclerostin. Finally, PTH induces the synthesis of IGF-I and, due to its prodifferentiating and pro-survival effects on osteoblasts, this could be a key mediator of PTH effect on osteoblasts. In conclusion, the intermittent administration of PTH has a pleiotropic anabolic effect on bone; further studies about mechanisms of action of PTH could be a starting point to new osteoporosis treatments.

Role of IGF-I on PTH effects on bone

IGF-I and PTH have synergistic actions on bone and some effects of the anabolic actions of PTH are mediated by local production of IGF-I, as has been shown in vitro and in vivo studies both in animals and humans. PTH can induce skeletal IGF-I expression both in vitro and in vivo. In chondrocytes, IGF-I synthesis is under GH control, whereas in osteoblasts its synthesis is fundamentally under the control of PTH. PTH stimulates the synthesis of IGF-I via a cAMP-dependent mechanism, and this factor has pro-differentiating and prosurvival effects on osteoblasts. In in vitro studies, IGF-I and PTH have shown a synergistic action on the osteoblasts of bone marrow. Human clinical data confirm the interactions between PTH and GH-IGF-I axis on bone. PTH is involved in the development of osteoporosis in adult patients with GH deficiency (GHD). In fact, patients with GHD show renal, skeletal, and intestinal cell insensitivity to PTH, leading to a mild state of PTH resistance and increased serum PTH levels. In addition, GH replacement in these patients restores PTH secretory rhythm, increases bone turnover markers, 1,25-dihydroxy vitamin D concentration, and Ca absorption/reabsorption, thus contributing to the positive effects of GH on bone. On the other hand, in post-menopausal women with primary hyperparathyroidism a reduced secretion of GH is observed, in association with a greater impairment of bone mass. GH administration resulted in increased IGF-I concentration, decreased PTH concentration, and increased nephrogenous cAMP. In conclusion, the anabolic action of PTH requires paracrine and autocrine effects of IGF-I.

Selective killing of human cancer cells by targeting a fusion mRNA between CYCLIN D1 and TROP2

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Background: Trop-2 is a calcium signal transducer and a stem cell marker. Trop-2 is widely overexpressed by human cancers and stimulates their growth. A TROP2 mRNA was isolated as post-transcriptionally joined to CYCLIN D1 transcripts, suggesting this as one of the transforming mechanisms of TROP2. Methods: In vitro cell growth assays were utilized to assess the cell growth stimulatory capacity of the chimeric mRNA. Colony assays for growth in soft agarose and tumorigenicity assays in nude mice were utilized to assess for the transforming capacity of the fusion transcript. siRNA constructs were utilized for the stably shut-down of the expression of the CYCLIN D1-TROP2 mRNA. Results: The chimeric mRNA transforms primary cells in vitro and induces aggressive tumor growth in vivo in cooperation with activated RAS. The CYCLIN D1-TROP2 mRNA is expressed by a large fraction of human ovarian, endometrial and gastro-intestinal tumors. The chimera is coexpressed with activated RAS in a subset of tumors, consistent with a cooperative transforming activity. The chimeric mRNA is a bicistronic transcript that independently translates wild type Cyclin D1 and Trop-2 proteins, i.e. it does not generate chimeric, oncogenic proteins. On the other hand, joining to the stable TROP2 mRNA leads to a higher CYCLIN D1 mRNA stability, with inappropriate persistence during the cell cycle and acquisition of transforming capacity. As essentially no normal tissues express the chimeric mRNA, we targeted it for destruction in cancer cells with stably expressed siRNA constructs. Specific targeting led to essential annnihilation of the CYCLIN D1-TROP2 mRNA, in the absence of off-target effects. Silencing of the chimeric mRNA blocked the growth of expressing breast cancer cells. Conclusions: Our findings demonstrate a novel, widespread oncogenic mechanism in human cancers, and open novel avenues for mRNA-targeted anti-cancer therapies. Acknowledgments This work was supported by the the Fondazione of the Cassa di Risparmio della Provincia di Chieti, the Association for the Application of Biotechnology in Oncology (ABO and ABO Project S.p.A., grant no. VE01D0019) and the Marie Curie Transfer of Knowledge Fellowship, contract number 014541.

No significant financial relationships to disclose.

Weekly clodronate treatment prevents bone loss and vertebral fractures in women with subclinical Cushing's syndrome

INTRODUCTION

Chronic mild endogenous glucocorticoid excess has been shown to cause bone loss and to increase fracture risk in both post-menopausal and premenopausal women. Currently, it is unclear if patients with subclinical Cushing's syndrome (SCS) with osteoporosis or osteopenia may benefit from antiresorptive treatment and the type of therapy to be given.

OBJECTIVE

This pilot randomized study was aimed at evaluating the effects of 12-month im administration of clodronate (100 mg every week) on vertebral and femoral bone mineral density (BMD), bone turnover markers and on subjective pain in premenopausal women with SCS due to adrenal incidentalomas.

METHODS

Forty-six women (age, 43.1+/-7.7 yr) with SCS due to adrenal incidentaloma and osteoporosis/osteopenia were randomized to receive clodronate plus supplement of Calcium (500 mg daily) and Vitamin D3 (800 mg daily) (group 1, no.=23) or supplements only (group 2, no.=23). Both groups were similar in terms of age, body mass index, cortisol levels, BMD values, and bone turnover markers. All of the women were re-evaluated after 12 months.

RESULTS

After 12 months of treatment, in group 1, a significant increase in lumbar BMD occurred (p=0.04), while bone turnover markers decreased by about one third (p<0.05). In group 2, bone turnover markers did not change and BMD values slightly decreased (p=ns). The differences in bone turnover markers and in lumbar BMD between the two groups were significant (p<0.05, all). No new vertebral fracture occurred in group 1, while in group 2 the spine radiographies revealed 2 new fractures and a worsening of two pre-existent fractures. An improvement in subjective back pain, assessed by visual analogue scale pain score was observed in group 1 (from 4.3+/-2.7 to 2.9+/-2.0; p<0.05) but not in group 2 (from 4.4+/-3.1 to 4.2+/-3.4; p=ns). No significant changes occurred in cortisol secretion or clinical picture of the SCS during the study.

CONCLUSIONS

Intramuscular administration of clodronate effectively increased lumbar BMD values, preserved bone mass at the femoral neck, stabilized vertebral fracture index, and decreased subjective back pain in pre-menopausal women with SCS. Since the untreated group continued to lose bone, antiresorptive treatment should be considered in patients with SCS, according to the prevision of surgical treatment, prevalent fractures, BMD values, age, concomitant morbidities, and desire for pregnancy.

[Retractile mesenteritis: case report]

The Authors report a case al retractile mesenteritis. The disease is a chronic inflammation of the mesentery with the developement of fibrosis. The mesenteritis is a benign disease and sometimes it is related to urogenital neoplasm. The CT fìndings of mesenteritis are non specific and often is necessary a laparotomic or laparoscopic biopsy. The therapy in uncomplicated cases is steroid treatment.

The role of growth hormone in glucocorticoid-induced osteoporosis

Glucocorticoid-induced osteoporosis (GIO) is the most common form of secondary osteoporosis. GC influence bone metabolism via a modulation of different components of the GH/IGF-I system. GH has multiple anabolic effects on bone, either direct or mediated by IGF-I. GH-deficient subjects have significant reduction in bone mineralization, bone turnover markers, and increased fracture risk when compared with healthy age-matched controls. The increase of bone remodeling achieved by recombinant human GH (rhGH) therapy may be helpful in both males and females with decreased bone turnover and impaired osteoblastic function such as subjects with GC excess. rhGH treatment may improve lean body mass and skeletal muscle mass that may further reduce fracture risk in GIO patients. Nevertheless, the real efficacy of rhGH and IGF-I treatment in GIO and during aging is still controversial and further well-designed prospective controlled studies are necessary in order to clarify this issue, thus identifying who could potentially benefit from GH treatment.

Lack of in vivo embryotoxic and genotoxic activities of orally administered stem bark aqueous extract of Mangifera indica L. (Vimang)

Mango (Mangifera indica L.) stem bark aqueous extract (MSBE) is a new natural product with antioxidant, anti-inflammatory and immunomodulatory effects known by the brand name of its formulations as Vimang. Previously, the oral toxicity studies of the extract showed a low toxicity potential up to 2000 mg/kg. This work reports the results about teratogenic and genotoxicologic studies of MSBE. For embryotoxicity study, MSBE (20, 200, or 2000 mg/kg/day) was given to Sprague-Dawley rats by gavage on days 6-15 of gestation. For genotoxicity, MSBE was administered three times during 48 h to NMRI mice. Cyclophosphamide (50 mg/kg) was used as a positive control. No maternal or developmental toxicities were observed when the rats were killed on day 20th. The maternal body-weight gain was not affected. No dose-related effects were observed in implantations, fetal viability or external fetal development. Skeletal and visceral development was similar among fetuses from all groups. No genotoxicity was observed in bone marrow erythrocytes and liver cells after administration. MSBE appears to be neither embryotoxic nor genotoxic as measured by bone marrow cytogenetics in rodents.

TROP2 is a major determinant of growth and metastatic spreading of human cancer

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Background: The TROP2 gene encodes a transmembrane calcium signal transducer, involved in the regulation of cell- cell adhesion. Methods: To identify the role of Trop-2 in transformed cells, we studied its expression pattern and function by DNA array and SAGE analysis, Northern and Western blotting, flow cytometry, confocal microscopy and IHC in experimental systems and in man. Overexpression or down-regulation of Trop-2 and directed mutagenesis were used to identify its role in tumor growth and metastasis in vivo. Results: DNA microarray, EST, SAGE, RT-PCR and Northern blot analysis of human tumors revealed expression of the TROP2 gene in most cancers. IHC analysis of human tumors (1755 cases) revealed a corresponding overexpression of Trop-2 protein. Trop-2 potently stimulated the growth of tumor cells, whereas TROP2 siRNA inhibited it. Deletion of the cytoplasmic region of Trop-2 abolished the growth stimulatory capacity, as did mutagenesis of the S303 PKC phosphorylation site. Proteomic analysis showed that multiple PKC isoforms partecipate to the Trop-2 signaling network. In vivo imaging showed dynamic colocalization of PKCs and Trop-2 in vivo in membrane ruffles and podosomes. DN PKCs and siRNA abolished Trop-2-induced growth. Strikingly, comparative global gene expression analysis revealed that TROP2 was the only gene up-regulated across different metastatic models, tumor types and animal species. IHC analysis revealed a dramatic up-regulation in metastases from colon, stomach, breast and ovary tumors in man. To assess if Trop-2 may play a causal role in metastatic spreading, TROP2-transfected KM12SM colon cancer cells were orthotopically injected in nude mice. TROP2-overexpressing transfectants demonstrated increased metastatic potential to the liver. Deletion of the HIKE domain of Trop-2 severely diminished, whereas that of the whole cytoplasmic region vastly increased metastatic diffusion, indicating the existence of both metastatic enhancers and silencers in the Trop-2 cytoplasmic tail. Conclusions: Our findings demonstrate that Trop-2 is a novel, widespread, stimulator of human cancer growth and a unique marker and causal factor of metastatic cancer, and candidate Trop-2 as a target of novel diagnostic and therapeutic procedures.

No significant financial relationships to disclose.

Renal transplantation in children younger than 6 years old

Herein we report our experience in renal transplantation in 38 children (40 transplants), ages 1 to 5 years, between 1989 and 2005. Demographics as well as patient and graft survivals are reported. Mean age at transplantation was 3.3 +/- 1.3 years, and mean weight was 14 kg (range, 5.7-25 kg); 92.5% were Caucasian, 7.5% African-Brazilian. The main etiology for end-stage renal disease (ESRD) was uropathic/vesicoureteral reflux (45%) followed by glomerulopathy (25%), congenital/hereditary diseases (10%), and hemolytic uremic syndrome (12.5%). Prior to transplantation, 5% were on hemodialysis, 85% on peritoneal dialysis, and 10% preemptive. All children were followed for at least 6 months posttransplantation, except 2 who died in the first month. In 75% of cases, kidneys were obtained from living-related donors, and in 25% from deceased donors. Thirty-nine kidneys were extraperitoneally placed. Primary immunosuppressant therapy consisted of cyclosporine (61%), tacrolimus (39%), mycophenolate (49%), and azathioprine (51%). A steroid-free protocol was used in 17% of patients. In the last 21 cases, basiliximab or daclizumab was added. There were 13 (32.5%) graft losses (4 artery/vein thromboses, 3 chronic rejections, 3 deaths, 3 other causes). The 5-year patient and graft survival rates were 89.6% and 72.2%. We have concluded that renal transplantation can be performed with good long-term results in children younger than 6 years old.

300 Pediatric Renal Transplantations: A Single-Center Experience

Our objective was to relate the results of 300 consecutive kidney transplants performed in children at a single center.

PATIENTS AND METHODS

An analysis of kidney transplants was performed on patients less than 18 years old engrafted from May 1977 to August 2005.

RESULTS

Among 300 kidney transplants, 48% of the patients were female, 87% were Caucasian, and 13% were African-Brazilian. The mean age at transplant was 11.5 +/- 4.5 years with 39 (13%) less than 6 years of age. The most frequent etiology of renal failure was vesicoureteral reflux/obstructive uropathy (36%) followed by glomerulopathy (27%). The donor was deceased in 32.3% and living related in 77.7% (parents 82%). The mean posttransplant follow-up was 4.8 +/- 4.3 years. The initial immunosuppression was CyA + AZA + PRED in 45%; CyA + MMF + PRED in 9.6%; TAC + AZA + PRED in 7.3%; TAC + MF + PRED in 9.7%; or TAC + MF without PRED in 10%. Sirolimus was employed initially in three cases. Induction with OKT3/ATG occurred in three patients and 112 received an anti-IL2 receptor antibody. The 103 graft losses during 28 years of follow-up were secondary to chronic allograft nephropathy in 51 (49.5%), vascular thrombosis in 5 (4.8%), acute rejection in 12 (11.6%), and recurrence of original disease in 13 (12.6%). Sixteen (15.5%) died with functioning grafts. Graft survival in the first, fifth, and tenth year were 90%, 72%, and 59%, respectively. Patient survival in the first, fifth, and tenth years were 95%, 93%, and 85%, respectively, with infection as the main cause of death.

[Mini-laparoscopic cholecystectomy: indications, technique and results]

The improvement of results and patients quality life is the aim of surgical technique. Mini-laparoscopic cholecystectomy brings not only to a better cosmetic results, but also to a decrease of post operative pain, analgesic use, hospital stay and an early return to normal activities. In this study, Authors report their own experience about mini-laparoscopic cholecystectomy using 5 mm and 3 mm trocar. Patients suffering from biliary sludge, microscopic lithiasis and mild or moderate gallbladder inflammation can undergo this procedure.

New perspectives in the medical treatment of acromegaly

Currently available medical treatment of acromegaly includes dopamine agonists, slow release formulation of somatostatin analogues and pegvisomant, a GH-receptor antagonist. Dopamine agonists are well tolerated, not expensive but poorly effective. Somatostatin analogues are highly effective in 60-70% of patients based on the receptor profile of individual tumors. Pegvisomant is reported to normalize IGF-I levels in nearly the totality of the patients, but is devoted of tumor shrinking effect. In a preliminary study in patients with acromegaly, a new somatostatin analogue with affinity to four of the five somatostatin receptors (SOM230) was shown to be similarly effective as octreotide in some patients and more effective than octreotide in other patients. Moreover, new molecules with selective activity on the somatostatin receptor type 2, or 5, or 1 have been reported in vitro to strongly suppress GH secretion. Other new promising alternatives are the chimeric compounds with both somatostatin receptor and dopamine receptor binding. These drugs have been also shown to possess strong GH-inhibitory activity in primary cultures from GH-secreting adenomas. These drugs are the future perspectives in the treatment of patients with GH-secreting or GH/PRL-secreting tumors.

Area under the curve of methotrexate and creatinine clearance are outcome-determining factors in primary CNS lymphomas

Although high-dose methotrexate (HD-MTX) is the most effective drug against primary CNS lymphomas (PCNSL), outcome-determining variables related to its administration schedule have not been defined. The impact on toxicity and outcome of the area under the curve (AUC(MTX)), dose intensity (DI(MTX)) and infusion rate (IR(MTX)) of MTX and plasmatic creatinine clearance (CL(crea)) was investigated in a retrospective series of 45 PCNSL patients treated with three different HD-MTX-based combinations. Anticonvulsants were administered in 31 pts (69%). Age >60 years, anticonvulsant therapy, slow IR(MTX) (</=800 mgm(-2)h(-1)), and reduced DI(MTX) (</=1000 mgm(-2)wk(-1)) were significantly correlated with low AUC(MTX) values. Seven patients (16%) experienced severe toxicity, which was independently associated with slow CL(crea). A total of 18 (40%) patients achieved complete remission after chemotherapy, which was independently associated with slow CL(crea). In all, 22 patients were alive at a median follow-up of 31 months, with a 3-year OS of 40+/-9%; slow CL(crea) and AUC(MTX) >1100 micromol hl(-1) were independently associated with a better survival. Slow CL(crea) and high AUC(MTX) are favourable outcome-determining factors in PCNSL, while slow CL(crea) is significantly related to higher toxicity. AUC(MTX) significantly correlates with age, anticonvulsant therapy, IR(MTX), and DI(MTX). These findings, which seem to support the choice of an MTX dose >/=3 gm(-2) in a 4-6-h infusion, every 3-4 weeks, deserve to be assessed prospectively in future trials. MTX dose adjustments in patients with fast CL(crea) should be investigated.

Neurogenic arthropathy of the knee due to chronic alcoholism: two case reports

The authors report two cases of neurogenic arthropathy of the knee in patients affected by chronic alcoholism. The aim of the authors is to discuss the etiopathogenic theory (neurotraumatic or/and neurovascular) as well as the mechanism by which alcohol damages joints.

Osteorticular amyloidosis in a patient under dialysis treated by total hip arthroplasty: case report and review of the literature

The authors present the case of a patient affected by kidney failure, who had been undergoing dialysis for several years when areas of osteolysis and bone resorption in the proximal femur and pathologic fracture appeared. She was treated surgically by hybrid total hip arthroplasty. The patient also complained of pains in other joints. The bone tissue taken from the osteolytic area was examined histologically. The test showed the presence of an amyloid substance. Microradiography and X-ray diffractometry carried out on the same samples confirmed the lack of mineralisation due to the presence of aluminum ions, presumably derived from dialysis. The high concentration of this element was confirmed by resum assay with spectrophometry in atomic absorption. Considering the results of the aforementioned tests, the patient was put on dialysis using a polymethylmethacrylate filter.

Hip arthroplasty after femoral osteotomy

Osteotomy of the proximal femur is performed to treat numerous hip pathologies in order to improve the load axis of the coxofemoral joint, thus improving coverage of the femoral head; despite this, arthrosis-related pathology may progress, and this nearly always results in hip arthroplasty. Many authors report that the time interval between osteotomy and arthroplasty is approximately 5 to 10 years. It is the purpose of this study to evaluate the complications and the clinical and radiographic results of hip arthroplasty performed after proximal femoral osteotomy, comparing them with a control group for hip arthroplasty without previous osteotomy.