Gut Microbiota, Immune System, and Bone.

The gut microbiota (GM) is the whole of commensal, symbiotic, and pathogenic microorganisms living in our intestine. The GM-host interactions contribute to the maturation of the host immune system, modulating its systemic response. It is well documented that GM can interact with non-enteral cells such as immune cells, dendritic cells, and hepatocytes, producing molecules such as short-chain fatty acids, indole derivatives, polyamines, and secondary bile acid. The receptors for some of these molecules are expressed on immune cells, and modulate the differentiation of T effector and regulatory cells: this is the reason why dysbiosis is correlated with several autoimmune, metabolic, and neurodegenerative diseases. Due to the close interplay between immune and bone cells, GM has a central role in maintaining bone health and influences bone turnover and density. GM can improve bone health also increasing calcium absorption and modulating the production of gut serotonin, a molecule that interacts with bone cells and has been suggested to act as a bone mass regulator. Thus, GM manipulation by consumption of antibiotics, changes in dietary habits, and the use of pre- and probiotics may affect bone health. This review summarizes evidences on the influence of GM on immune system and on bone turnover and density and how GM manipulation may influence bone health.

Lenalidomide normalizes tumor vessels in colorectal cancer improving chemotherapy activity.

BACKGROUND: Angiogenesis inhibition is a promising approach for treating metastatic colorectal cancer (mCRC). Recent evidences support the seemingly counterintuitive ability of certain antiangiogenic drugs to promote normalization of residual tumor vessels with important clinical implications. Lenalidomide is an oral drug with immune-modulatory and anti-angiogenic activity against selected hematologic malignancies but as yet little is known regarding its effectiveness for solid tumors. The aim of this study was to determine whether lenalidomide can normalize colorectal cancer neo-vessels in vivo, thus reducing tumor hypoxia and improving the benefit of chemotherapy. METHODS: We set up a tumorgraft model with NOD/SCID mice implanted with a patient-derived colorectal cancer liver metastasis. The mice were treated with oral lenalidomide (50 mg/Kg/day for 28 days), intraperitoneal 5-fluorouracil (5FU) (20 mg/Kg twice weekly for 3 weeks), combination (combo) of lenalidomide and 5FU or irrelevant vehicle. We assessed tumor vessel density (CD146), pericyte coverage (NG2; alphaSMA), in vivo perfusion capability of residual vessels (lectin distribution essay), hypoxic areas (HP2-100 Hypoxyprobe) and antitumor activity in vivo and in vitro. RESULTS: Treatment with lenalidomide reduced tumor vessel density (p = 0.0001) and enhanced mature pericyte coverage of residual vessels (p = 0.002). Perfusion capability of tumor vessels was enhanced in mice treated with lenalidomide compared to controls (p = 0.004). Accordingly, lenalidomide reduced hypoxic tumor areas (p = 0.002) and enhanced the antitumor activity of 5FU in vivo. The combo treatment delayed tumor growth (p = 0.01) and significantly reduced the Ki67 index (p = 0.0002). Lenalidomide alone did not demonstrate antitumor activity compared to untreated controls in vivo or against 4 different mCRC cell lines in vitro. CONCLUSIONS: We provide the first evidence of tumor vessel normalization and hypoxia reduction induced by lenalidomide in mCRC in vivo. This effect, seemingly counterintuitive for an antiangiogenic compound, translates into indirect antitumor activity thus enhancing the therapeutic index of chemotherapy. Our findings suggest that further research should be carried out on synergism between lenalidomide and conventional therapies for treating solid tumors that might benefit from tumor vasculature normalization.

Treatment with intermittent PTH increases Wnt10b production by T cells in osteoporotic patients.

UNLABELLED: We evaluated the effect of parathyroid hormone (PTH) on Wnt10b production by immune system cells in humans. We showed that bone anabolic effect of intermittent PTH treatment may be amplified by T cells through increased production of Wnt10b. Chronic increase in PTH as in primary hyperparathyroidism does not increase Wnt10b expression. INTRODUCTION: The aim of this study is to assess the effect of PTH on Wnt10b production by immune system cells in humans. We assessed both the effect of intermittent PTH administration (iPTH) and of chronic PTH hypersecretion in primary hyperparathyroidism (PHP). METHODS: Eighty-two women affected by post-menopausal osteoporosis were randomly assigned to treatment with calcium and vitamin D alone (22) or plus 1-84 PTH (42), or intravenous ibandronate (18). Wnt10b production by unfractioned blood nucleated cells and by T, B cells and monocytes was assessed by real-time RT-PCR and ELISA at baseline, 3, 6, 12 and 18 months of treatment. The effect of chronic elevation of PTH was evaluated in 20 patients affected by PHP at diagnosis and after surgical removal of parathyroid adenoma. WNT10b from both osteoporotic and PHP patients was compared to healthy subjects matched for age and sex. RESULTS: iPTH increases Wnt10b production by T cells, whereas PHP does not. After surgical restoration of normal parathyroid function, WNT10b decreases, although it is still comparable with healthy subjects' level. Thus, chronic elevation of PTH does not significantly increase WNT10b production as respect to control. CONCLUSIONS: This is the first work showing the effect of both intermittent and chronic PTH increase on Wnt10b production by immune system cells. We suggest that, in humans, T cells amplified the anabolic effect of PTH on bone, by increasing Wnt10b production, which stimulates osteoblast activity.

Incidence of primary and second cancers in renal transplant recipients: a multicenter cohort study.

Limited data exist about cancer prognosis and the development of second cancers in renal transplant recipients. In a retrospective cohort study on 3537 patients incidence rates of the first and, if any, of a second cancer, and standardized incidence ratios [SIR (95% CI)] were computed. Two hundred and sixty-three (7.5%) patients developed a NMSC, and 253 (7.2%) another type of cancer after a median follow-up of 6.5 and 9.0 years, respectively. A statistically significant excess risk, if compared to an age- and sex-matched reference general population, was observed for Kaposi sarcoma and NMSC, followed by non-Hodgkin lymphoma and carcinoma of cervix uteri; a small number of unusual cancers such as tumors of the salivary glands, small intestine and thyroid also were detected at a level worthy of additional scrutiny. Ten-year survival rate of all noncutaneous cancers was 71.3%, with lower rates for lung carcinoma and non-Hodgkin lymphoma (0% and 41.7%, respectively). Patients with NMSC had an increased risk of developing a second NMSC [SIR 8.3 (7.0-10.0)], and patients with a primary noncutaneous cancer had increased risk of developing a second noncutaneous cancer [SIR 1.8 (1.2-2.8)], if compared to the whole cohort. Our study underscore that the high risk of primary and second cancer in renal transplant recipients, including unusual cancers.

Teriparatide increases the maturation of circulating osteoblast precursors.

UNLABELLED: This study shows that teriparatide promotes the circulating osteoblast (OB) precursor degree of maturation in patients affected by postmenopausal osteoporosis. INTRODUCTION: Anabolic treatment with teriparatide has proven effective for the therapy of postmenopausal osteoporosis and significantly reduces the risk of non-vertebral fragility fractures. The aim of this study was to investigate the effect of teriparatide on circulating OB precursors. METHODS: We evaluated by flow cytometry and real-time PCR the expression of OBs typical markers in peripheral blood mononuclear cells during treatment with teriparatide plus calcium and vitamin D, raloxifene plus calcium and vitamin D or calcium and vitamin D alone at various time points. Serum bone alkaline phosphatase and osteocalcin (OC) were measured as markers of bone turnover. RESULTS: Our results show that circulating OB precursors are more numerous and more immature in patients affected by fragility fractures than in osteoporotic patients without fractures. We also show that teriparatide treatment increases the expression of alkaline phosphatase and of OC in OB precursors; thus, it increases their degree of maturation. CONCLUSIONS: We suggest that teriparatide acts as anabolic agents also by promoting the maturation of OB precursors.

Bone and bone marrow pro-osteoclastogenic cytokines are up-regulated in osteoporosis fragility fractures.

UNLABELLED: This study evaluates cytokines production in bone and bone marrow of patients with an osteoporotic fracture or with osteoarthritis by real time PCR, Western blot and immunohistochemistry. We demonstrate that the cytokine pattern is shifted towards osteoclast activation and osteoblast inhibition in patients with osteoporotic fractures. INTRODUCTION: Fragility fractures are the resultant of low bone mass and poor bone architecture typical of osteoporosis. Cytokines involved in the control of bone cell maturation and function are produced by both bone itself and bone marrow cells, but the roles of these two sources in its control and the amounts they produce are not clear. This study compares their production in patients with an osteoporotic fracture and those with osteoarthritis. METHODS: We evaluated 52 femoral heads from women subjected to hip-joint replacement surgery for femoral neck fractures due to low-energy trauma (37), or for osteoarthritis (15). Total RNA was extracted from both bone and bone marrow, and quantitative PCR was used to identify the receptor activator of nuclear factor kB Ligand (RANKL), osteoprotegerin (OPG), macrophage colony stimulating factor (M-CSF), transforming growth factor ß (TGFß), Dickoppf-1 (DKK-1) and sclerostin (SOST) expression. Immunohistochemistry and Western blot were performed in order to quantify and localize in bone and bone marrow the cytokines. RESULTS: We found an increase of RANKL/OPG ratio, M-CSF, SOST and DKK-1 in fractured patients, whereas TGFß was increased in osteoarthritic bone. Bone marrow produced greater amounts of RANKL, M-CSF and TGFß compared to bone, whereas the production of DKK-1 and SOST was higher in bone. CONCLUSIONS: We show that bone marrow cells produced the greater amount of pro-osteoclastogenic cytokines, whereas bone cells produced higher amount of osteoblast inhibitors in patients with fragility fracture, thus the cytokine pattern is shifted towards osteoclast activation and osteoblast inhibition in these patients.

Evaluation of oral-motor movements and speech in patients with tetanus of a public service in Brazil.

The characterisation of oral-motor movements and speech of patients with tetanus were investigated to determine the existence of possible signs that are characteristic of this pathology. Thirteen patients clinically diagnosed with tetanus (10 with severe tetanus and three with very severe tetanus) and admitted to an intensive care unit underwent clinical evaluation of oral-motor movements and speech. Statistical analysis indicated significant between-group differences for speech motor functions, suggesting that individuals with very severe tetanus present rigidity as a characteristic interfering in articulatory precision (P = 0·035) and movement rate (P = 0·038). For lip closure, tongue movement, palatal elevation, gag reflex and voice quality, no between-group differences were identified for the specific abnormal characteristics. The observed abnormal results indicate that muscle strength and functional status of the oral-motor system presented by most of the participants of the study did not ensure the necessary integrity for satisfactory performance. The characterisation of the oral myofunctional aspects of patients with tetanus provides medical teams, patients and families with a wider and better description of the clinical situation, giving support to the diagnosis, prognostics and treatment.

Intercellular adhesion molecule 1 K469E gene polymorphism is associated with presence of skin lesions in Tunisian Behçet's disease patients.

Intercellular adhesion molecule 1 (ICAM1) gene polymorphisms have been implicated in the susceptibility to inflammatory diseases. The expression of both soluble and tissue ICAM1 were increased in Behçet's disease (BD) but the contribution of ICAM1 gene polymorphisms to this disease remains unknown. We sought to establish the association of ICAM1 gene K469E polymorphism in exon 6 with susceptibility for BD. One hundred and thirty-five Tunisian patients who satisfied the International Study Group criteria for BD and 157 healthy blood donor controls from the same geographic area were genotyped by polymerase chain reaction method for the K469E ICAM1 gene polymorphisms in exon 6. There were no significant differences in the distribution of the K469E allele or genotype frequencies between the BD patients and healthy controls in the ICA1 gene. Among patients, significant association was found between the presence of skin lesions and the studied polymorphism in the distribution of the K469E allele (P = 0.004; odds ratio = 1.26; 95% confidence interval = 2.13-3.62) and genotype frequencies (P = 0.0028; chi(2) = 11.75). Our findings suggest that K469E ICAM1 gene polymorphism was associated with Tunisian BD patients with skin lesions.

Randomized controlled trial comparing the effectiveness of 308-nm excimer laser alone or in combination with topical hydrocortisone 17-butyrate cream in the treatment of vitiligo of the face and neck.

BACKGROUND: Vitiligo is a pigmentary disorder which may have disfiguring consequences. Its treatment remains a challenge. OBJECTIVES: We designed a parallel-group randomized controlled trial to compare the effectiveness of 308-nm excimer laser alone or in combination with topical hydrocortisone 17-butyrate cream in patients with vitiligo unresponsive to previous treatment with topical steroids or narrow-band ultraviolet (UV) B phototherapy. METHODS: Consecutive patients aged 18-75 years with nonsegmental vitiligo localized on the face and/or neck lacking response to previous conventional treatment were eligible. In total, 84 patients (44 women and 40 men, mean age 44 years) were randomized to 308-nm excimer laser phototherapy twice weekly alone or in combination with topical hydrocortisone 17-butyrate cream twice daily for three periods of 3 weeks followed by a 1-week steroid-free interval. The primary outcome was a reduction of at least 75% of the overall lesional areas as judged by automatic image analysis on reflected UV photographs, conducted blind to treatment assignment, at 12 weeks compared with baseline. Secondary outcomes were clearance, and improvements on Physician's Global Assessment (PGA) and Skindex-29 scores. RESULTS: A total of 76 (90%) patients completed the study. In an intention-to-treat analysis, seven [16.6%; 95% confidence interval (CI) 5.3-27.8%] patients in the excimer monotherapy arm and 18 (42.8%; 95% CI 27.8-57.8%) in the combination arm showed > or = 75% reduction of vitiligo lesions at 12 weeks (chi(2) test 6.89, P = 0.0087). Clearance was observed in two (4.7%; 95% CI 1.6-11.2%) and nine (21.4%; 95% CI 9.0-33.8%) patients, respectively (Fisher's exact test P = 0.04). A significant difference also emerged for PGA scores, while no difference was documented for Skindex-29. CONCLUSIONS: Recalcitrant vitiligo of the face and neck may benefit from the combination of excimer laser phototherapy with topical hydrocortisone 17-butyrate cream.

A natural auto-inhibitory factor of the terminal complement pathway in serum of Ctenodactylus gondi.

The serum of Ctenodactylus gondi, a Tunisian rodent, contains a unique inhibitor of the terminal complement pathway. The auto-inhibitor has been partially characterized as a heat-stable euglobulin that is slightly retarded on a DEAE-ion exchange column at pH 7 and elutes as a symmetrical peak on Sephacryl S-300 in the mol. wt region of approximately 200,000. The inhibitor acts by preventing attachment of cytolytic C5b-9 complexes to natural target cells. It does not appear to affect formation and function of C3-convertase, does not exert inhibitory effects at stages later than C5b-7 formation, and also does not prevent formation of SC5b-9 in serum. That the factor prevents attachment of C5b-7/C5b-9 to cells has been demonstrated in hemolysis model systems using sheep EA + human serum, and in the C3-independent reactive lysis system with the use of ELISA methods and quantitative assays with radioiodinated C8. Addition of partially purified inhibitory factor to human sera or to sera of other animal species abolishes the hemolytic activities of these sera. The inhibitory factor of Gondi serum is the first inhibitor of the terminal pathway which has been shown to be capable of preventing cytolysis of cells undergoing complement attack under physiological conditions. The presence of this factor is probably partially responsible for the remarkable susceptibility of C. gondi towards bacterial and parasitic infections.

Vaccines for preventing hepatitis B in health-care workers.

BACKGROUND: Hepatitis B causes acute and chronic liver disease and may be prevented by vaccination. OBJECTIVES: To assess the effectiveness and safety of plasma-derived vaccines against acute and chronic hepatitis B in health-care workers in protecting them from hepatitis B infection and its consequences. SEARCH STRATEGY: MEDLINE and Excerpta Medica Database (EMBASE) search using standard Cochrane strategy, Cochrane Library, full text searching of the journal "Vaccine", bibliography of retrieved studies and correspondence with authors, researchers and manufacturers. SELECTION CRITERIA: All original prospective randomised comparisons of yeast-derived vaccines and plasma-derived vaccines against no intervention, placebo, or vaccines against other disease (control vaccines). Assessment of trial quality was made according to: 1. generation of allocation schedule 2. measure(s) taken to conceal treatment allocation 3. drop-out of allocated health-care worker participants from the analysis of trial results 4. measures taken to implement double blinding Trial reports were blinded by removal of authors and their affiliation, journal reference, introduction, results, and discussion. DATA COLLECTION AND ANALYSIS: To assess efficacy the incidence rates of acute hepatitis B were observed in the surveillance of the vaccinated and control groups of the trials included in the review. Safety was assessed from side-effect rates, classified as systemic (malaise, nausea, fever, arthralgias, rash, headache) or local (induration and soreness at the site of the inoculation). MAIN RESULTS: Four trials fulfilling the criteria were identified and the data synthesised. All trials compared plasma-derived vaccines versus placebo. Differences in the settings (and level of incidence) between three of the trial settings and Dienstag's led us to stratify our comparison grouping the three trials performed in dialysis units together. After our stratification, the Desmyter, Smuzness and Crosnier group appears to be homogeneous (Chi-square = 0.11, degrees of freedom = 2). Our estimates of effectiveness and safety in the high risk group favour treatment, the OR for cases of HB being 0.34; 95% CI (0.21, 0.55). The analysis also revealed a non-significant trend towards benefit in the lower risk health-care workers (Dienstag trial, OR 0.26 (0.05, 1.30). Overall the evidence strongly favours vaccination (OR=0.33; 95% CI (0.21, 0.53)). There was no difference in the incidence and severity of side-effects between the two arms of the trials. We calculated that it was necessary to vaccinate between 145 (assuming a baseline rate of 10 cases/1000/year) and 7 (for a baseline rate of 200/1000/year) health-care workers with plasma-derived vaccines to avoid one case of hepatitis B. Completeness of trial reporting was not good with all four trials failing to report titre results on antibodies against hepatitis B surface antigen and hepatitis B core antigen in the placebo arms (correspondence with two of the four authors failed to shed light on the reasons for such an omission). All four trials achieved low scores in the four quality dimensions assessed (generation of allocation schedule, measure(s) taken to conceal treatment allocation, exclusion of allocated participants from the analysis of the trial and measures taken to implement and protect double blinding). Mean length of follow-up was 14.5 months. REVIEWER'S CONCLUSIONS: Plasma-derived vaccines appear to be efficacious and safe for use in high risk health-care workers, such as staff of renal dialysis and transplant units. There is some uncertainty concerning the effectiveness of the vaccine in lower risk health-care workers, although the trend is towards benefit. We found no evidence of a long-term protective effect due to the short follow-up time of the four trials included in this review. We found relatively poor standard of trial reporting, possibly related to the age of the trials.

A cost-utility analysis of patients undergoing orthognathic treatment for the management of dentofacial disharmony.

INTRODUCTION: Management of dentofacial discrepancies using orthognathic treatment is now a common procedure in the United Kingdom. Although the benefits of orthognathic intervention are often considered, the cost implications have not been investigated to our knowledge. This study is a cost-utility analysis of orthognathic treatment. PATIENTS AND METHODS: Twenty-one patients were interviewed five times during treatment using the time trade-off (TTO) method to establish utility values. Quality adjusted life years (QALYs) gained as a result of treatment were calculated and discounted. The resource use was calculated for each of the 21 patients individually and the costs subjected to both a sensitivity analysis and discounting. The incremental mean cost per additional QALY was calculated (as compared with a 'no treatment' approach). RESULTS: The incremental cost for each additional QALY was 561 pounds sterling for the groups combined, based on mean additional costs and QALYs (546 pounds sterling for the bimaxillary group and 617 pounds sterling for the single jaw group). DISCUSSION: Orthognathic treatment seems to provide good outcomes at relatively low cost. Even allowing for the uncertainty in mean costs and QALYs, there is a high probability of treatment being cost-effective. Cost-utility analysis is still a relatively new technique in dentistry and further studies should be encouraged.

Cost analysis of nurse telephone consultation in out of hours primary care: evidence from a randomised controlled trial.

OBJECTIVE: To undertake an economic evaluation of nurse telephone consultation using decision support software in comparison with usual general practice care provided by a general practice cooperative. DESIGN: Cost analysis from an NHS perspective using stochastic data from a randomised controlled trial. SETTING: General practice cooperative with 55 general practitioners serving 97 000 registered patients in Wiltshire, England. SUBJECTS: All patients contacting the service, or about whom the service was contacted during the trial year (January 1997 to January 1998). MAIN OUTCOME MEASURES: Costs and savings to the NHS during the trial year. RESULTS: The cost of providing nurse telephone consultation was 81 237 pound sterling per annum. This, however, determined a 94 422 pound sterling reduction of other costs for the NHS arising from reduced emergency admissions to hospital. Using point estimates for savings, the cost analysis, combined with the analysis of outcomes, showed a dominance situation for the intervention over general practice cooperative care alone. If a larger improvement in outcomes is assumed (upper 95% confidence limit) NHS savings increase to 123 824 pound sterling per annum. Savings of only 3728 pound sterling would, however, arise in a scenario where lower 95% confidence limits for outcome differences were observed. To break even, the intervention would have needed to save 138 emergency hospital admissions per year, around 90% of the effect achieved in the trial. Additional savings of 16 928 pound sterling for general practice arose from reduced travel to visit patients at home and fewer surgery appointments within three days of a call. CONCLUSIONS: Nurse telephone consultation in out of hours primary care may reduce NHS costs in the long term by reducing demand for emergency admission to hospital. General practitioners currently bear most of the cost of nurse telephone consultation and benefit least from the savings associated with it. This indicates that the service produces benefits in terms of service quality, which are beyond the reach of this cost analysis.

Met signaling regulates growth, repopulating potential and basal cell-fate commitment of mammary luminal progenitors: implications for basal-like breast cancer.

Basal-like breast cancer is an aggressive subtype of mammary carcinoma. Despite expressing basal markers, typical of mammary stem cells, this tumor has been proposed to originate from luminal progenitors, which are downstream of stem cells along the mammary epithelial hierarchy. This suggests that committed luminal progenitors may reacquire basal, stem-like characteristics, but the mechanisms that regulate this transition remain unclear. Using mouse models, we found that luminal progenitors express high levels of the Met receptor for hepatocyte growth factor (HGF), as compared with the other mammary epithelial sub-populations. Constitutive activation of Met led luminal progenitors to attain stem cell properties, including enhanced clonogenic activity in vitro and de novo ability to reconstitute mammary glands in repopulation assays in vivo. Moreover, in response to Met signaling, luminal progenitors gave rise to hyperplastic ductal morphogenesis and preferentially underwent basal lineage commitment at the expense of luminal cell-fate specification. Opposite and symmetric results were produced by systemic pharmacological inhibition of Met. Hence, Met signaling targets luminal progenitors for expansion, impairs their differentiation toward the mature luminal phenotype and enables their commitment toward the basal lineage. These results emphasize a critical role for Met in promoting deregulated proliferation and basal plasticity of normal luminal progenitors in the mammary gland, a complex of events that may be required for sustaining the functional and phenotypic properties of basal-like breast tumors.