Platelet-derived growth factor-D enables liver myofibroblasts to promote tumor lymphangiogenesis in cholangiocarcinoma

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Paraoxonase polymorphisms PON1 192 and 55 and longevity in Italian centenarians and Irish nonagenarians. A pooled analysis

BACKGROUND: PON1, an arylesterase, associated with high density lipoprotein (HDL), protects low density lipoprotein (LDL) against oxidative modification. Common polymorphisms PON1 55 (L/M) and 192 (Q/R) in the PON1 gene associate with atherosclerosis and heart disease. Because long-lived people seem protected from premature vascular death, we conducted a pooled statistical analysis to assess any association between these polymorphisms and longevity in a large combined group of Italian centenarians and octo/nonagenarians from Northern Ireland (NI). MATERIALS AND METHODS: Separated DNA was available from 1479 subjects from Italy and Northern Ireland (NI). In Italy 308 centenarians (males 67, females 241, mean age 100.8, SD2.1 years) and 579 young controls (males 347, females 232, mean age 40.7, SD 12.7 years) were included in the study. In NI, 296 octo/nonagenarians (males 92, females 204, mean age 89.8, SD 5.7 years) and 296 young sex-matched subjects (mean age 13.0, SD 1.4 years) had available DNA. PON1 55 (L/M) and 192 (Q/R) polymorphisms were studied using a PCR-RFLP approach. RESULTS: There was a significant difference in PON1 192 genotypes in Italian centenarians compared to younger controls (X(2)= 6.8, df = 2 p= 0.03) and a similar but non significant trend between octo/nonagenarian and young subjects in NI (X(2) = 4.0, df=2, p=0.14). Using logistic regression analysis on the combined Italian and Irish datasets, there was a small survival advantage for centenarian and octo/nonagenarian subjects who were heterozygous for PON1 192 R allele, (OR 1.3, CI 1-1.6; p=0.04 with a stepwise increase for RR homozygous subjects (OR 1.7, CI 1.1-2.6; p = 0.02) compared to QQ subjects. Comparing R and Q alleles there was a survival advantage for octo/nonagenarian/centenarian subjects who carried the R allele (OR 1.3, CI 1.1-1.5; p = 0.007) but there was no sex-specific effect p =0.77) LL, LM and MM genotypes of PON 55 polymorphisms showed similar frequencies in Italy (39.9, 47.0, 13.1%) and Ireland (39.5, 48.6, 11.9%) with no age or sex-related differences. The PON1 192R/Q and PON55L/M loci were in strong linkage disequilibrium with a Lewontin's D' coefficient -0.928 (elderly) and -0.965 (young). There was a significant difference in haplotype frequency of these linked loci in older compared to younger subjects (Likelihood Ratio X(2) = 9.60, df = 3, p= 0.02). CONCLUSION: These data suggest a modest association between the 192R allele and longevity in two very elderly populations in two European countries. Being homozygous for 192 RR further enhances survival advantage but this effect was not found to be sex specific. This finding is of interest because the 192R allele has previously been associated with increased risk of coronary heart disease. On the other hand, the 192R allele shows higher enzymatic activity, using paraoxon as substrate, and we postulate that its role in the metabolism of potentially toxic chemicals or other metabolic pathways may be important in survival to very old age.     

Mixed cryoglobulinemia: demographic, clinical, and serologic features and survival in 231 patients

BACKGROUND: Mixed cryoglobulinemia (MC) is a systemic vasculitis secondary to circulating immune complex deposition in the small vessels. In the overwhelming majority of patients, hepatitis C virus (HCV) infection represents the triggering factor of the disease. MC is characterized by multiple organ involvement, mainly skin, liver, renal, peripheral nerves, and less frequently by widespread vasculitis and cancer. OBJECTIVES: To investigate the demographic, clinical, serologic features, and survival in a large series of MC patients. METHODS: The study included 231 MC patients recruited between 1972 and 2001 at the Rheumatology Unit of the University of Pisa. All patients underwent wide clinicoserologic and virologic assessment. Cumulative survival rates were computed by the Kaplan-Meier method; moreover, the prognostic relevance of the main variables was investigated by Cox model analysis. RESULTS: In 92% of cases, the presence of HCV infection was demonstrated (anti-HCV antibody, 92%; HCV RNA, 90%), whereas hepatitis B virus (HBV) represented the possible causative agent in only 1.8% of patients (HBV DNA). Clinically, the MC syndrome followed a relatively benign clinical course in over 50% of cases, whereas a moderate-severe clinical course was observed in one third of patients whose prognosis was severely affected by renal and/or liver failure. In a limited, but significant, percentage (15%) of individuals, the disease was complicated by a malignancy, ie, B-cell lymphoma, and less frequently by hepatocellular carcinoma, or thyroid cancer. The survival study by the Kaplan-Meier method revealed a significantly lower cumulative 10th-year survival, calculated from time of diagnosis, in MC patients compared with expected death in the age- and sex-matched general population. Moreover, significantly lower survival rates were observed in males and in subjects with renal involvement. The multivariate analysis by the Cox proportional hazard regression model further supported the above findings: an increased mortality risk of 98% was observed for male gender (male/female hazard ratio, 1.978) and of 197% in patients with, compared with those without, renal involvement (hazard ratio, 2.967). At the end of the follow-up, 97 patients were deceased, and in 79 of 97 patients, the causes of death were ascertained: nephropathy (33%), malignancies (23%), liver involvement (13%), and diffuse vasculitis (13%) were the most frequent causes of death. CONCLUSIONS: Careful patient monitoring is recommended for a timely diagnosis of life-threatening MC complications, mainly nephropathy, widespread vasculitis, and B-cell lymphoma or other malignancies.     

Hb Southern Italy: coexistence of two missence mutations (the Hb Sun Prairie alpha2 130 Ala --> Pro and Hb Caserta alpha2 26 Ala --> Thr) in a single HBA2 gene

This study describes a new molecular condition in the alpha(2)-globin gene (HBA2) found in six unrelated families from Southern Italy (Campania and Sicily). This new double mutant form of haemoglobin is called Hb Southern Italy and originated from the coexistence of two known mutations occurring in the same globin gene, HBA2 26 G-->A (Hb Caserta) and HBA2 130 G-->C (Hb Sun Prairie). Hb Sun Prairie was originally observed in Indian patients in either the homozygous state, with severe hemolytic anemia, and in the heterozygous state with microcytosis, or in asymptomatic cases as an alpha-thalassemia carrier phenotype. Hb Caserta was observed for the first time in a Casertian family (South Italy) that displayed a slowmigrating haemoglobin upon investigation. We report the clinical phenotype and molecular study of this new double mutant form of haemoglobin in heterozygous and homozygous subjects, as well as in association with alpha degrees delectional thalassemia.     

The influence of the crutch setup on stability and weight-bearing parameters in post total hip replacement surgery patients during quiet standing

Purpose: The purpose of this study is to evaluate the influence of the crutch setup on standing, in post total hip replacement (THR) surgery patients.

Materials and methods: Thirty patients after THR were randomly assigned to walking with the elbow flexed (EF) or elbow straight (ES) crutch setup. Subjects were asked to stand on a force platform in a comfortable position with the crutch positioned on the unaffected side, facing forward for 10?seconds. Centre of pressure total path and maximal excursion were evaluated in both medio-lateral and anterior–posterior planes. Difference in the asymmetry of left/right acromial height, measured with and without the crutch, was calculated (ACdiff). Percentage of body weight borne by the crutch (Fcr), symmetry (SIload) between operated and healthy limbs loading during the trial, together with shoulder forces and moments were measured.

Results: No significant differences between the two groups (p?>?.05) were found for stability parameters. ACdiff, Fcr and shoulder load increased significantly (p?Conclusions: The present study showed that the ES setup reduced the force borne by the crutch, the load on the shoulder joint and it minimized postural and loading asymmetries when compared to EF setup. Conversely, postural stability was not influenced by the crutch setup.

• Implications for Rehabilitation

• Static posture and weight-bearing parameters are influenced by crutch setup during quiet standing.

• Crutch setup does not influence postural stability.

• Adjusting the crutch according to the elbow straight setup reduces the force borne by the crutch and the asymmetry in lower limbs loading.

• Forces and moments at the shoulder joint were reduced for the elbow straight setup group.

     

Antibacterial‐nanocomposite bone filler based on silver nanoparticles and polysaccharides

Injectable bone fillers represent an attractive strategy for the treatment of bone defects. These injectable materials should be biocompatible, capable of supporting cell growth and possibly able to exert antibacterial effects. In this work, nanocomposite microbeads based on alginate, chitlac, hydroxyapatite and silver nanoparticles were prepared and characterized. The dried microbeads displayed a rapid swelling in contact with simulated body fluid and maintained their integrity for more than 30 days. The evaluation of silver leakage from the microbeads showed that the antibacterial metal is slowly released in saline solution, with less than 6% of silver released after 1 week. Antibacterial tests proved that the microbeads displayed bactericidal effects toward Staphylococcus aureus, Pseudomonas aeruginosa and Staphylococcus epidermidis, and were also able to damage pre‐formed bacterial biofilms. On the other hand, the microbeads did not exert any cytotoxic effect towards osteoblast‐like cells. After characterization of the microbeads bioactivity, a possible means to embed them in a fluid medium was explored in order to obtain an injectable paste. Upon suspension of the particles in alginate solution or alginate/hyaluronic acid mixtures, a homogenous and time‐stable paste was obtained. Mechanical tests enabled to quantify the extrusion forces from surgical syringes, pointing out the proper injectability of the material. This novel antibacterial bone filler appears as a promising material for the treatment of bone defects, in particular when possible infections could compromise the bone‐healing process. Copyright © 2016 John Wiley & Sons, Ltd.     

Nonunion fracture healing: Evaluation of effectiveness of demineralized bone matrix and mesenchymal stem cells in a novel sheep bone nonunion model

Nonunion treatment has a high rate of success, although recalcitrant nonunion may determine the need for amputation. Therefore, new treatment options are continuously investigated in order to further reduce the risk of nonunion recurrence. This study aimed to (a) develop a new large animal model for bone atrophic nonunion and (b) compare the efficacy of demineralized bone matrix (DBM) and DBM in combination with mesenchymal stem cells (MSC) in the new nonunion model. The new model consists of a noncritical, full‐thickness segmental defect created in the sheep tibia, stabilized by an intramedullary nail, and involves the creation of a locally impaired blood supply achieved through periosteum excision and electrocauterization of the stump ends. Six weeks after defect creation, lack of hard tissue callus and established nonunion was observed in all operated tibiae both by radiographic and clinical evaluation. Nonunion was treated with allogeneic DBM or autologous MSC cultivated on DBM particles (DBM + MSC) for 1 day before implantation. Twelve weeks after treatment, radiographic, microtomographic, histologic, and histomorphometric analysis showed the formation of bone callus in DBM group, whereas the fracture healing appeared at an early stage in DBM + MSC group. Torsional strength and stiffness of the DBM group appeared higher than those of DBM + MSC group, although the differences were not statistically significant. In conclusion, a new sheep bone nonunion model resembling the complexity of the clinical condition was developed. DBM is an effective option for nonunion treatment, whereas MSC do not improve the healing process when cultivated on DBM particles before implantation.