The use of only enamel matrix derivative allows outstanding regeneration results in periodontal intrabony defect treatment: a retrospective study

Periodontal tissue regeneration depends on several biological, homeostatic and regulative variables that directly induce the clinical features. The aim of this study is to compare the clinical results obtained using the enamel matrix derivative peptide (EMP) compared to the less manageable association of EMP and bovine bone xenographic (BPBM) in the treatment of deep intraosseous defects. Ten healthy patients, suffering from moderate or severe chronic periodontitis, having at least two deep and narrow intrabony defects in the same dental arch and needing surgical treatment, were selected. The same patient was treated with the two different materials: EMP -TG1 in one defect and the association-TG2 in the other. Immediately before surgery (T0) and 12-month after (T2) the probing depth (PD) and gingival recession (GR) were registered at the experimental sites. No statistically significant differences were shown between TG1 and TG2 at T0 nor at T1 in term of PD and GR, while a statistically significant PD decrease was found both in TG1 and TG2 between T0 and T1 (p less than 0.05). GR increase resulted statistically significant in TG1 (p less than 0.05) but not in TG2 between T0 and T1 (p≥0.05). In this split-mouth retrospective study, both the treatments achieve favourable clinical results but the TG1 shows a significant increase in GR probably because EMP is not able to support the gingiva covering the intrabony defect. Therefore, the choice of the type of periodontal defect to be treated with EMP will be a therapeutic key-point.

Hybrid procedures and femoral endarterectomy in diabetic patients

OBJECTIVE

The aim of the study is to evaluate the safety and effectiveness of common femoral endarterectomy (CFE) in critical limb ischemia (CLI) associated with proximal and distal endovascular (EV) revascularization in diabetic (type 1 and type 2) and non-diabetic patients.

PATIENTS AND METHODS

We analyzed patients from January 2008 to December 2011 who underwent one-staged hybrid procedures. Patients were divided into three groups: group 1 = EV reconstruction proximal to the CFE, group 2 = EV procedures distal to the CFE, group 3 = both proximal and distal EV procedures. Patients were evaluated at 6 and 36 months after the procedures, and the mean follow-up was 42 ± 20.3 months.

RESULTS

A total of 43 (79% men; aged 74.4 ± 8.6 years) out of 635 (5.5%) patients operated for CLI fulfilled the inclusion criteria; 23 (53.5%) had type 1 or type 2 diabetes mellitus (DM). DM patients were younger than controls (p = 0.048). The patient distribution was 14 in Group 1 (32.5%), 24 in Group 2 (55.8%) and 5 in Group 3 (11.7%). CFE was successful in all cases, while associated EV procedures were successful in 90.7% of patients. Peri-operative morbidity and mortality were 11.6% and 2.3%, respectively. Survival rates at 6 and 36 months were 93% and 71.9%, respectively. Three patients (6.98%) underwent a major amputation. The cumulative limb salvage was 95.2% at 6 months and 92.1% at 36 months. No recurrent CFE stenosis was observed. No differences in survival, amputation or patency rates emerged between DM and non-DM patients or among the three EV revascularization groups.

CONCLUSIONS

Hybrid procedures are safe and effective both in CLI patients with or without DM, and they should be taken into consideration whenever indications are present.

Treatment of acne with a combination of propolis, tea tree oil, and Aloe vera compared to erythromycin cream: two double-blind investigations

Introduction

Antibiotics that suppress Propionibacterium acnes are the standard treatment for acne but are becoming less effective, due to the appearance of antibiotic-resistant strains. Many plants are known to have innate antimicrobial action and can be used as alternatives to antibiotics; thus, it is necessary to prove their effectiveness in vivo. This study aimed to evaluate the anti-acne efficacy of a new cream based on three natural extracts, comparing it to erythromycin cream and placebo.

Patients and methods

Sixty patients with mild to moderate acne vulgaris were randomly divided into three groups: treated with cream containing 20% propolis, 3% "tea tree oil", and 10% "Aloe vera" (PTAC) (n=20); or with 3 % erythromycin cream (ERC) (n=20); or with placebo (n=20). At baseline, after 15 and 30 days, investigators evaluated response to treatment by counting acne lesions through noninvasive measurements and macrophotography.

Results

All the clinical and instrumental values studied were statistically different from placebo except for sebometry, pHmetry, and erythema index values, measured on healthy skin. Unlike in the placebo group, papular and scar lesions showed high erythema reduction after 15 and 30 days of PTAC and ERC application.

Conclusion

The PTAC formulation was better than ERC in reducing erythema scars, acne severity index, and total lesion count.

Are contemporary femoral components sizing and design likely to affect functional results in TKA? A mathematical model of an implanted knee to predict knee forces

PURPOSE

This study is aimed to investigate the effects of the choice of femoral and tibial components on several mechanical outputs that might be associated with total knee replacement surgery outcomes using a validated computational model: the Kansas knee simulator.

METHODS

Two models from the same range of implants were taken into account: Model 1, the femoral component fitted the femoral epiphysis, with physiological positioning of the articulating surface using a 10-mm-thick tibial component, and in Model 2, the femoral component was 4 mm smaller than in Model 1, and a 14-mm-thick tibial component was used with a similar tibial resection and the tibio-femoral joint line was 4 mm more proximal to compensate the increased posterior bone resection and maintain proper soft-tissue tension in flexion. Changes in reaction forces and contact pressures between the components, changes in extensor muscle forces and changes in patello-femoral joint kinematics during walking gait have been studied.

RESULTS

While the computational model predicted that most kinematic and kinetic outputs, including tibio-femoral and patello-femoral joint motions, contact forces, pressures and areas, were similar for Model 1 and Model 2, and a dramatic difference has been found in the extensor muscle forces necessary to flex and extend the knee. To reproduce the same knee motion with a knee reconstructed as in Model 2, a patient would need to generate approximately 40% greater extensor muscle force throughout the gait cycle in order to do so.

CONCLUSION

As a consequence of such a large increase in the extensor muscle force, the knee motions would probably be compromised and, subsequently, a patient with a knee reconstructed as in Model 2 would be less likely to be able to reproduce normal knee function and therefore more likely to report poor outcome.

Retrospective Analysis of 156 Cases of Metastatic Renal Cell Carcinoma: Evaluation of Prognostic Factors and Response to Different Treatments

Background

Metastatic renal cell carcinoma is a “capricious” tumor. Many prognostic factors have been evaluated, treatment is still controversial, and results are not coincident.

Methods

We reviewed 156 patients with metastatic renal cell carcinoma. Survival from the time of diagnosis was the end point of the study. The influence on survival of age, sex, nephrectomy, disease-free interval, performance status, site and number of metastases was analyzed. Univariate and multivariate analysis were done. Survival according to different therapies was also evaluated.

Results

In our study, no nephrectomy, a disease-free interval < 24 months, > 2 metastatic sites and a performance status > 2 proved to be risk factors. According to the number of risk factors, 3 groups of patients were identified (low, intermediate and high risk). We observed 3 kinds of responses to treatments: 1) in untreated patients (n = 48), median overall survival was 6 months, and the 24-month survival rate was 8%; 2) in patients treated with hormone therapy and/or chemotherapy (n = 73), median overall survival was 13 months, and the 24-month survival rate was 24%; 3) in patients treated with interferon and/or interleukin-2 (n = 35), median overall survival was 16 months and the 24-month survival rate was 34%.

Conclusions

Our results are only partially in accordance with those observed by other authors. Risk factors and treatment must be determined in more defined and selected studies.

Alternating block copolymer-based nanoparticles as tools to modulate the loading of multiple chemotherapeutics and imaging probes

Cancer therapy often relies on the combined action of different molecules to overcome drug resistance and enhance patient outcome. Combined strategies relying on molecules with different pharmacokinetics often fail due to the lack of concomitant tumor accumulation and, thus, to the loss of synergistic effect. Due to their ability to enhance treatment efficiency, improve drug pharmacokinetics, and reduce adverse effects, polymer nanoparticles (PNPs) have been widely investigated as co-delivery vehicles for cancer therapies. However, co-encapsulation of different drugs and probes in PNPs requires a flexible polymer platform and a tailored particle design, in which both the bulk and surface properties of the carriers are carefully controlled. In this work, we propose a core-shell PNP design based on a polyurethane (PUR) core and a phospholipid external surface. The modulation of the hydrophilic/hydrophobic balance of the PUR core enhanced the encapsulation of two chemotherapeutics with dramatically different water solubility (Doxorubicin hydrochloride, DOXO and Docetaxel, DCTXL) and of Iron Oxide Nanoparticles for MRI imaging. The outer shell remained unchanged among the platforms, resulting in un-modified cellular uptake and in vivo biodistribution. We demonstrate that the choice of PUR core allowed a high entrapment efficiency of all drugs, superior or comparable to previously reported results, and that higher core hydrophilicity enhances the loading efficiency of the hydrophilic DOXO and the MRI contrast effect. Moreover, we show that changing the PUR core did not alter the surface properties of the carriers, since all particles showed a similar behavior in terms of cell internalization and in vivo biodistribution. We also show that PUR PNPs have high passive tumor accumulation and that they can efficient co-deliver the two drugs to the tumor, reaching an 11-fold higher DOXO/DCTXL ratio in tumor as compared to free drugs. STATEMENT OF SIGNIFICANCE: Exploiting the synergistic action of multiple chemotherapeutics is a promising strategy to improve the outcome of cancer patients, as different agents can simultaneously engage different features of tumor cells and/or their microenvironment. Unfortunately, the choice is limited to drugs with similar pharmacokinetics that can concomitantly accumulate in tumors. To expand the spectrum of agents that can be delivered in combination, we propose a multi-compartmental core-shell nanoparticles approach, in which the core is made of biomaterials with high affinity for drugs of different physical properties. We successfully co-encapsulated Doxorubicin Hydrochloride, Docetaxel, and contrast agents and achieved a significantly higher concomitant accumulation in tumor versus free drugs, demonstrating that nanoparticles can improve synergistic cancer chemotherapy.

Progression-dependent transport heterogeneity of breast cancer liver metastases as a factor in therapeutic resistance

Metastatic disease is a major cause of mortality in cancer patients. While many drug delivery strategies for anticancer therapeutics have been developed in preclinical studies of primary tumors, the drug delivery properties of metastatic tumors have not been sufficiently investigated. Therapeutic efficacy hinges on efficient drug permeation into the tumor microenvironment, which is known to be heterogeneous thus potentially making drug permeation heterogeneous, also. In this study, we have identified that 4 T1 liver metastases, treated with pegylated liposomal doxorubicin, have unfavorable and heterogeneous transport of doxorubicin. Our drug extravasation results differ greatly from analogous studies with 4 T1 tumors growing in the primary site. A probabilistic tumor population model was developed to estimate drug permeation efficiency and drug kinetics of liver metastases by integrating the transport and structural properties of tumors and delivered drugs. The results demonstrate significant heterogeneity in metastases with regard to transport properties of doxorubicin within the same animal model, and even within the same organ. These results also suggest that the degree of heterogeneity depends on the stage of tumor progression and that differences in transport properties can define transport-based tumor phenotypes. These findings may have valuable clinical implications by illustrating that therapeutic agents can permeate and eliminate metastases of "less resistant" transport phenotypes, while sparing tumors with more "resistant" transport properties. We anticipate that these results could challenge the current paradigm of drug delivery into metastases, highlight potential caveats for therapies that may alter tumor perfusion, and deepen our understanding of the emergence of drug transport-based therapeutic resistance.

Design, development, and testing of an environmental P-T cell for infrared spectroscopy measurements

Water absorption bands due to superficially adsorbed molecules often dominate the near-infrared spectra of particulate minerals and rocks, when measured in the laboratory in the reflectance mode. In order to remove this, the spectral effect is thus necessary to acquire spectra of samples in vacuum and at higher temperatures. With the aim to accomplish this task, we developed an environmental cell to perform infrared spectroscopic measurements at controlled pressure-temperature conditions. Currently the cell allows one to measure reflectance spectra in the temperature range from room values up to 300 °C (573 K), in the pressure range of 10³-10^-6 mbar. The acquisition of spectra continuously in two distinct phases, namely, during a preliminary pumping stage (at room T) and subsequently during a heating stage (in vacuum), permits to highlight and characterize separately the effect of pressure and temperature on infrared spectra.

Correction function for accuracy improvement of the Composite Smeared Finite Element for diffusive transport in biological tissue systems

Modeling of drug transport within capillaries and tissue remains a challenge, especially in tumors and cancers where the capillary network exhibits extremely irregular geometry. Recently introduced Composite Smeared Finite Element (CSFE) provides a new methodology of modeling complex convective and diffusive transport in the capillary-tissue system. The basic idea in the formulation of CSFE is in dividing the FE into capillary and tissue domain, coupled by 1D connectivity elements at each node. Mass transport in capillaries is smeared into continuous fields of pressure and concentration by introducing the corresponding Darcy and diffusion tensors. Despite theoretically correct foundation, there are still differences in the overall mass transport to (and from) tissue when comparing smeared model and a true 3D model. The differences arise from the fact that the smeared model cannot take into account the detailed non-uniform pressure and concentration distribution in the vicinity of capillaries. We introduced a field of correction function for diffusivity through the capillary walls of smeared models, in order to have the same mass accumulation in tissue as in case of true 3D models. The parameters of the numerically determined correction function are: ratio of thickness and diameter of capillary wall, ratio of diffusion coefficient in capillary wall and surrounding tissue; and volume fraction of capillaries within tissue domain. Partitioning at the capillary wall - blood interface can also be included. It was shown that the correction function is applicable to complex configurations of capillary networks, providing improved accuracy of our robust smeared models in computer simulations of real transport problems, such as in tumors or human organs.

Integrated waveguides and deterministically positioned nitrogen vacancy centers in diamond created by femtosecond laser writing

Diamond's nitrogen vacancy (NV) center is an optically active defect with long spin coherence times, showing great potential for both efficient nanoscale magnetometry and quantum information processing schemes. Recently, both the formation of buried 3D optical waveguides and high-quality single NVs in diamond were demonstrated using the versatile femtosecond laser-writing technique. However, until now, combining these technologies has been an outstanding challenge. In this Letter, we fabricate laser-written photonic waveguides in quantum grade diamond which are aligned to within micron resolution to single laser-written NVs, enabling an integrated platform providing deterministically positioned waveguide-coupled NVs. This fabrication technology opens the way toward on-chip optical routing of single photons between NVs and optically integrated spin-based sensing.

Combined Use of DNA Probes in First-Trimester Prenatal Diagnosis of Hemophilia A

First-trimester prenatal diagnoses of hemophilia A were heretofore obtained by using either intragenic factor VIII markers or linked cxtragcnic polymorphic markers. Postulating that the combined use of all the available intragenic and extragenic markers can render such diagnoses more frequently feasible and more reliable, we carried out ten first-trimester prenatal diagnoses in male fetuses at risk for hemophilia A by DNA analysis of chorionic villus employing in combination the intragenic Bcl I polymorphism and the St 14 (DXS 52) or DX 13 (DXS 15) extragenic probes. A diagnosis of hemophilia was obtained in three fetuses, with a diagnosis of normal fetus obtained in the remaining seven. Seven diagnoses are confirmed by factor VIII assays carried out at the time of abortion, in the mid-Trimester or at birth. A factor VIII probe recognizing Bcl I polymorphism was useful in 4 of 6 diagnoses; St 14, in 5 of 6; and DX 13 in 3 of 5. In two cases, St 14 was the only useful probe for diagnosis. Even though no recombination between extragenic probes and factor VIII gene was detected in this study, when only extragenic markers were informative we advised diagnostic confirmation on fetal plasma obtained by fetoscopy. Hence, first-trimester prenatal diagnosis of hemophilia A is feasible for the great majority of fetuses at risk through combined use of all the available intragenic and extragenic probes, providing key family members are available.

Multiscale smeared finite element model for mass transport in biological tissue: From blood vessels to cells and cellular organelles

One of the basic and vital processes in living organisms is mass exchange, which occurs on several levels: it goes from blood vessels to cells and organelles within cells. On that path, molecules, as oxygen, metabolic products, drugs, etc. Traverse different macro and micro environments - blood, extracellular/intracellular space, and interior of organelles; and also biological barriers such as walls of blood vessels and membranes of cells and organelles. Many aspects of this mass transport remain unknown, particularly the biophysical mechanisms governing drug delivery. The main research approach relies on laboratory and clinical investigations. In parallel, considerable efforts have been directed to develop computational tools for additional insight into the intricate process of mass exchange and transport. Along these lines, we have recently formulated a composite smeared finite element (CSFE) which is composed of the smeared continuum pressure and concentration fields of the capillary and lymphatic system, and of these fields within tissue. The element offers an elegant and simple procedure which opens up new lines of inquiry and can be applied to large systems such as organs and tumors models. Here, we extend this concept to a multiscale scheme which concurrently couples domains that span from large blood vessels, capillaries and lymph, to cell cytosol and further to organelles of nanometer size. These spatial physical domains are coupled by the appropriate connectivity elements representing biological barriers. The composite finite element has "degrees of freedom" which include pressures and concentrations of all compartments of the vessels-tissue assemblage. The overall model uses the standard, measurable material properties of the continuum biological environments and biological barriers. It can be considered as a framework into which we can incorporate various additional effects (such as electrical or biochemical) for transport through membranes or within cells. This concept and the developed FE software within our package PAK offers a computational tool that can be applied to whole-organ systems, while also including specific domains such as tumors. The solved examples demonstrate the accuracy of this model and its applicability to large biological systems.

Possible Correlation between Some Biologic Effects and the Clinical Course in Patiens Treated with Continuous Infusion of Interleukin-2 plus Alpha-2 Interferon for Metastatic Renal Cell Carcinoma

Background

Interleukin-2 therapy is known to cause many biologic effects, which are enhanced by the administration of interferon prior to or immediately after interleukin-2 infusion. Some of these effects could be related to the clinical response.

Methods

Sixteen patients with metastatic renal cell carcinoma were treated with continuous infusion of interleukin-2 plus alpha-2 interferon. Differential leukocyte count and lymphocyte subset evaluation were performed every 3 days during interleukin-2 treatment. At each cycle, the presence of the following antibodies was tested: antithyroid, antinuclear, antiplatelet and antierythrocyte.

Results

Fifteen patients were evaluable for response. No complete response was observed. Five patients obtained partial response (33%) and 3 stable disease (20%): 2 of them underwent surgical resection of metastases and obtained complete response. Some of our patients showed a significant increase in eosinophils, CD25+ lymphocytes and antithyroid antibodies. The association of these parameters, calculated with a “score” system, was also related to a better clinical response.

Conclusions

Eosinophils, CD25+ lymphocytes and antithyroid antibodies could have a predictive value for the efficacy of interleukin-2 and alpha-2 interferon therapy in metastatic renal cell carcinoma.

Thrombotic Microangiopathy of the Miscellaneous Secondary Type Responding to Plasma Exchange in a Liver Transplant Recipient

A thrombotic microangiopathy syndrome, clinically and pathologically similar to thrombotic thrombocytopenic purpura (TTP) has been reported in recipients of tissue transplants, including renal and bone marrow allografts. The diagnosis is made only after other causes of microangiopathic hemolytic anemia have been excluded. In this case report we present the outcome of the combination of plasma exchange, dipyridamole and aspirin in the management of a TTP-like syndrome that complicated the post-operative course of liver transplantation.

Aging resistance, mechanical properties and translucency of different yttria-stabilized zirconia ceramics for monolithic dental crown applications

OBJECTIVES

The dental market moves towards high-translucency monolithic zirconia dental crowns, which are usually placed either with - or without - a thin glaze layer. The microstructural features and the mechanical performances of these materials are still controversial, as well as their susceptibility to aging. This paper aims at studying these aspects in the current generation of zirconia dental crowns showing different degrees of translucency.

METHODS

Four different commercial zirconia materials were investigated, including one standard 'full-strength' 3Y-TZP and three grades with improved translucency. The microstructural features (phase composition and assemblage, grain size) were carefully studied, as well as mechanical properties (biaxial bending strength and indentation toughness), translucency and aging behavior (in autoclave at 134°C). Aging was conducted on crowns with and without glaze to better represent clinical uses.

RESULTS

Important differences are found in terms of microstructures among the materials in terms of cubic phase content and yttria in the tetragonal phase, leading to different optical, mechanical and aging resistance properties. We show that higher cubic phase content leads to better translucency and stability in water steam, but at the expense of strength and toughness. A compromise is always inevitable between translucency and aging resistance on one side and mechanical properties on the other side.

SIGNIFICANCE

A new technique for hemodilution, preparation of autologous platelet-rich plasma and intraoperative blood salvage in cardiac surgery

We have developed a new system for the production of autologous platelet-rich plasma and red blood cell concentrates to be used in autologous transfusion support of cardiac surgery patients. In 15 operations no homologous blood products were required. Costs were diminished since with the same harness it was possible to carry out the intraoperative blood salvage and concentrate the erythrocytes contained in the oxygenator and its lines. Indirect costs were also reduced since no infective complication was observed due to homologous blood products.