[An exceptional cause of pacemaker dysfunction]

Twiddler syndrome is a very rare and surprising complication of pacemaker treatment. We report the case of a woman with psychiatric disease who presented two cardiac arrests due to loss of ventricular capture. Finally, pacemaker retropectoral implantation resolves the problem.

Machine learning on brain MRI data for differential diagnosis of Parkinson's disease and Progressive Supranuclear Palsy

BACKGROUND

Supervised machine learning has been proposed as a revolutionary approach for identifying sensitive medical image biomarkers (or combination of them) allowing for automatic diagnosis of individual subjects. The aim of this work was to assess the feasibility of a supervised machine learning algorithm for the assisted diagnosis of patients with clinically diagnosed Parkinson's disease (PD) and Progressive Supranuclear Palsy (PSP).

METHOD

Morphological T1-weighted Magnetic Resonance Images (MRIs) of PD patients (28), PSP patients (28) and healthy control subjects (28) were used by a supervised machine learning algorithm based on the combination of Principal Components Analysis as feature extraction technique and on Support Vector Machines as classification algorithm. The algorithm was able to obtain voxel-based morphological biomarkers of PD and PSP.

RESULTS

The algorithm allowed individual diagnosis of PD versus controls, PSP versus controls and PSP versus PD with an Accuracy, Specificity and Sensitivity>90%. Voxels influencing classification between PD and PSP patients involved midbrain, pons, corpus callosum and thalamus, four critical regions known to be strongly involved in the pathophysiological mechanisms of PSP.

COMPARISON WITH EXISTING METHODS

Classification accuracy of individual PSP patients was consistent with previous manual morphological metrics and with other supervised machine learning application to MRI data, whereas accuracy in the detection of individual PD patients was significantly higher with our classification method.

CONCLUSIONS

The algorithm provides excellent discrimination of PD patients from PSP patients at an individual level, thus encouraging the application of computer-based diagnosis in clinical practice.

Pharmaco-proteomics opportunities for individualizing neurovascular treatment

Neurovascular disease often involves multi-organ system injury. For example, patent foramen ovale (PFO) related ischemic strokes involve not just the brain, but also the heart, the lung, and the peripheral vascular circulation. For higher-risk but high-reward systemic therapy (e.g., thrombolytics, therapeutic hypothermia (TH), PFO closure) to be implemented safely, very careful patient selection and close monitoring of disease progression and therapeutic efficacy are imperative. For example, more than a decade after the approval of therapeutic hypothermic and intravenous thrombolysis treatments, they both remain extremely under-utilized, in part due to lack of clinical tools for patient selection or to follow therapeutic efficacy. Therefore, in understanding the complexity of the global effects of clinical neurovascular diseases and their therapies, a systemic approach may offer a unique perspective and provide tools with clinical utility. Clinical proteomic approaches may be promising to monitor systemic changes in complex multi-organ diseases - especially where the disease process can be 'sampled' in clinically accessible fluids such as blood, urine, and CSF. Here, we describe a 'pharmaco-proteomic' approach to three major challenges in translational neurovascular research directly at bedside - in order to better stratify risk, widen therapeutic windows, and explore novel targets to be validated at the bench - (i) thrombolytic treatment for ischemic stroke, (ii) therapeutic hypothermia for post-cardiac arrest syndrome, and (iii) treatment for PFO related paradoxical embolic stroke. In the future, this clinical proteomics approach may help to improve patient selection, ensure more precise clinical phenotyping for clinical trials, and individualize patient treatment.

A method for accurate zero calibration of asymmetric jaws in single-isocenter half-beam techniques

PURPOSE

To present a practical method for calibrating the zero position of asymmetric jaws that provides higher accuracy at the central axis and improves dose homogeneity in the abutting region of half-beams.

METHODS

Junction doses were measured for each asymmetric jaw using the double-exposure technique and electronic portal imaging devices. The junction dose was determined as a function of jaw position. The shift in the zero jaw position (or in its corresponding potentiometer readout) required to correct for the measured junction dose could thus be obtained. The jaw calibration was then modified to introduce the calculated shift and therefore achieve an accurate zero position in order to provide a relative junction dose that was as close to zero as possible.

RESULTS

All the asymmetric jaws from four medical linear accelerators were calibrated with the new calibration procedure. Measured relative junction doses at gantry 0° were reduced from a maximum of ±40% to a maximum of ±8% for all the jaws in the four considered accelerators. These results were valid for 6 MV and 18 MV photon beams and for any combination of asymmetric jaws set to zero. The calibration was stable over a long period of time; therefore, the need for recalibrating is seldom necessary.

CONCLUSIONS

Accurate calibration of the zero position of the jaws is feasible in current medical linear accelerators. The proposed procedure is fast and it improves dose homogeneity at the junction of half-beams, thus, allowing a more accurate and safer use of these techniques.

Cardiotoxicity of high-dose-rate epirubicin evaluated by angiocardioscintigraphy

Cardiotoxicity of high dose rate epirubicin (140-160 mg/m(2) as a bolus every 21 days up to a cumulative dose of 1280 mg/m(2)) was evaluated by angiocardioscintigraphy in 121 patients with advanced neoplastic disease and no preexisting cardiac risk factors. LVEF was measured in each patient before chemotherapy and during the treatment at different epirubicin cumulative dosages. The cases were subdivided into 3 groups: Group A=121 basal studies; Group B=93 studies performed under 800 mg/m(2); Group C=44 studies performed over 800 mg/m(2). A statistically significant decrease of LVEF was observed only at cumulative doses over 800 mg/m(2) (mean LVEF: 53% +/- 11% in Group C vs 64% +/- 7% in Group A). In no case was chemotherapy stopped prematurely and no case of heart failure was observed. A decrease of LVEF 10 units was recorded in 15 patients and 12 of them had been treated with over 800 mg/m(2). No clinical signs of severe cardiac failure were observed in these patients during a follow-up of 5-17 months. In conclusion, epirubicin treatment at high dose rate up to a cumulative dose of 1000 mg/m(2) does not increase the risk of clinically relevant cardiomyopathy and an LVEF decrease of 10 units should not in itself lead to chemotherapy termination in responsive patients.

Titanium Disk Surfaces Modulate Dental Implants Osseointegration

Titanium and titanium alloys are widely used as implant materials due to their excellent biocompatibility and mechanical properties. The aim of this work is to compare five different titanium layers in order to investigate which one had a greater osteoconductive power using Human Osteoblasts (HObs) culture for seven days on these surfaces. The expression levels of some bone-related genes (ALPL, COL1A1, COL3A1, SPP1, RUNX2 and SPARC) were analyzed using real time Reverse Transcription-Polymerase Chain Reaction (real time RT-PCR). Results obtained in this study demonstrate that titanium disks can lead to osteoblast differentiation and extracellular matrix deposition and mineralization by the activation of different osteoblast genes in relation to the specific type of surface treatment.

Gene Expression Study in Dental Pulp Stem Cells Cultivated on Titanium Alloys

Nowadays, research on orthopedic and dental implants is focused on titanium alloys due to their appropriated mechanical properties and corrosion resistance in the body environment. Another important aspect to be investigated is their surface topography, which is very important to osseointegration. The aim of this study was to assess dental pulp stem cells response to different titanium surface topography modified. Mesenchymal stem cell marker ENG was significantly decreased in stem cells cultivated in modified titanium surface respect to machined titanium surface, indicating the differentiation effect of this biomaterial on stem cells. The obtained results can be relevant to better understand the molecular mechanism of bone regeneration and as a model for comparing other materials with similar clinical effects.

Titanium Disk Surfaces Modulate Fibroblasts Behavior

Titanium (Ti) is the most widely used material in implantology for dental, orthopedic and maxillofacial purposes due to their excellent biocompatibility and mechanical properties Several data suggest that implant anchorage to bone and soft tissue can be modulated by surface characteristics. Fibroblasts are the soft tissues cells concerned in producing extracellular matrix and collagen. The aim of this work is to compare five different titanium surface treatments in order to investigate which one had the best behavior using Human Fibroblast (HFb) after seven days in culture medium. The expression levels of some adhesion and traction-resistance related genes (COL11A1, COL2A1, COL9A1, DSP, ELN, HAS1, and TFRC) were analyzed using real time Reverse Transcription-Polymerase Chain Reaction (real time RT-PCR). Titanium disks can lead to implant integration promoting the production of protein involved in cell-cell and cell-matrix adhesion and in stress-resistance, required for a good outcome in dental implantology

A multicenter phase III prospective randomized trial of high-dose epirubicin in combination with cyclophosphamide (EC) versus docetaxel followed by EC in node-positive breast cancer. GOIM (Gruppo Oncologico Italia Meridionale) 9902 study

BACKGROUND

The Gruppo Oncologico Italia Meridionale 9902 trial compared four cycles of high-dose epirubicin plus cyclophosphamide (EC) with four cycles of docetaxel (Taxotere, D) followed by four cycles of EC as adjuvant treatment of node-positive breast cancer.

PATIENTS AND METHODS

Patients were randomly assigned to EC (E 120 mg/m(2), C 600 mg/m(2), arm A) for four cycles or four cycles of D (100 mg/m(2)) followed by four cycles of EC (arm B), both regimens every 21 days. Hormone receptor-positive patients were given hormonal therapy for 5 years. Primary end point was 5-year disease-free survival (DFS). Secondary objectives were overall survival (OS) and safety.

RESULTS

There were 750 patients enrolled. With a median follow-up of 64 months, 5-year DFS was 73.4% in both arms, and 5-year OS was 89.5% versus 90.7% in arm A and B [hazard ratio was 0.99 (95% confidence interval for DFS 0.75-1.31; P = 0.95)], respectively. Grade 3-4 toxicity was more common in arm B.

CONCLUSIONS

This study did not show advantages from the addition of docetaxel to high-dose EC as adjuvant chemotherapy in node-positive breast cancer. The small sample size and low number of DFS events may have limited the ability to observe statistically significant difference between the two arms.

Ex vivo expansion of human Tregs by rabbit ATG is dependent on intact STAT3-signaling in CD4⁺ T cells and requires the presence of monocytes

The addition of low, nondepleting doses of rabbit antithymocyte globulin (ATG) to human peripheral blood mononuclear cells has been shown to expand functional CD4(+) CD25(+) FoxP3(+) regulatory T cells (Tregs) in vitro. This report is the first to elucidate the exact cellular mechanisms of ATG-mediated Treg expansion. CD4(+) T cells require monocytes, but not other antigen presenting cell subsets, to be present in coculture to expand Tregs. However, T cells do not require direct cell-cell contact with monocytes, suggesting the importance of soluble factors. Moreover, ATG initially "reprograms" CD4(+) T cells, but not monocytes, and induces STAT3 and STAT5 signaling in CD4(+) cells. These reprogrammed CD4(+) T cells subsequently secrete GM-CSF and IL-10 only in case of intact STAT3 signaling, which in turn promote the generation of tolerogenic CD14(+) CD11c(+) dendritic cells characterized by enhanced IL-10 and decreased IL-12 production. Treg expansion following ATG treatment is accompanied by enhanced gene expression of both GM-CSF and Bcl-2, but not TGF-β, in peripheral blood mononuclear cells. These results demonstrate that ex vivo expansion of human Tregs by ATG is due to its ability to reprogram CD4(+) T cells in a STAT3-dependent but TGF-β-independent manner, leading to the generation of monocyte-derived dendritic cells with a tolerogenic cytokine profile.

Evaluation of nilotinib in advanced GIST previously treated with imatinib and sunitinib

Purpose

Patients with advanced GIST following standard imatinib and sunitinib often have good performance status and need additional therapy. This study tested nilotinib, a second-generation tyrosine kinase inhibitor, in patients with advanced GIST refractory to standard therapies.

Methods

This single-center open-label phase II study has a primary objective to determine progression-free survival at 6 months. Using a novel statistical design, 17 patients were to be enrolled; if ≥10 were progression free (PF) at 2 months, 19 additional patients would be enrolled. The therapy was considered of benefit if ≥13 of 36 patients were PF at 6 months. All patients signed informed consent and entry criteria included normal cardiac function. Exploratory analyses correlating genotype with response were also performed.

Results

Thirteen patients were treated; 2 had received agents after imatinib and sunitinib. Treatment was well tolerated with one grade 4 anemia attributed to nilotinib. No measurable responses were observed; median time to progression was 2 months. One patient remained on study with stable disease for 12 months. Mutation testing is available from 10 primary tumors with 7 exon 11 mutations, 1 exon 9 mutation, and 2 without KIT/PDGFR mutations. Two samples from recurrent disease had 2 mutations, both primary exon 11 mutations with an additional exon 17 mutation, including the patient with prolonged stable disease.

Conclusions

Nilotinib was well tolerated in these patients with advanced GIST. Accrual was halted due to insufficient clinical benefit. However, nilotinib may provide benefit to specific subsets of advanced GIST with exon 17 mutations.

The design and delivery of a thermally responsive peptide to inhibit S100B-mediated neurodegeneration

S100B, a glial-secreted protein, is believed to play a major role in neurodegeneration in Alzheimer's disease, Down syndrome, traumatic brain injury, and spinocerebellar ataxia type 1 (SCA1). SCA1 is a trinucleotide repeat disorder in which the expanded polyglutamine mutation in the protein ataxin-1 primarily targets Purkinje cells of the cerebellum. Currently, the exact mechanism of S100B-mediated Purkinje cell damage in SCA1 is not clear. However, here we show that S100B may act via the activation of the receptor for advanced glycation end product (RAGE) signaling pathway, resulting in oxidative stress-mediated injury to mutant ataxin-1-expressing neurons. To combat S100B-mediated neurodegeneration, we have designed a selective thermally responsive S100B inhibitory peptide, Synb1-ELP-TRTK. Our therapeutic polypeptide was developed using three key elements: (1) the elastin-like polypeptide (ELP), a thermally responsive polypeptide, (2) the TRTK12 peptide, a known S100B inhibitory peptide, and (3) a cell-penetrating peptide, Synb1, to enhance intracellular delivery. Binding studies revealed that our peptide, Synb1-ELP-TRTK, interacts with its molecular target S100B and maintains a high S100B binding affinity as comparable with the TRTK12 peptide alone. In addition, in vitro studies revealed that Synb1-ELP-TRTK treatment reduces S100B uptake in SHSY5Y cells. Furthermore, the Synb1-ELP-TRTK peptide decreased S100B-induced oxidative damage to mutant ataxin-1-expressing neurons. To test the delivery capabilities of ELP-based therapeutic peptides to the cerebellum, we treated mice with fluorescently labeled Synb1-ELP and observed that thermal targeting enhanced peptide delivery to the cerebellum. Here, we have laid the framework for thermal-based therapeutic targeting to regions of the brain, particularly the cerebellum. Overall, our data suggest that thermal targeting of ELP-based therapeutic peptides to the cerebellum is a novel treatment strategy for cerebellar neurodegenerative disorders.

Early laparoscopic Kasai's procedure in a low weight newborn

The authors present an early laparoscopic treatment in a newborn with biliary atresia. They describe the technical details of the Kasai laparoscopic procedure. A 10-day-old girl, weight 2.4 kg, was admitted with a history of jaundice and fecal acholia since birth, with elevated total bilirubin and abnormal hepatic test. Abdominal ultrasound showed a small gallbladder with hyperechogenicity in porta hepatis and absence of biliary principal duct. Other metabolic and hematological tests were normal. The procedure was performed at 20-day-old by laparoscopy. The cholangiography confirmed the biliary atresia and Kasai's procedure was continued by laparoscopy and transumbilical extracorporeal Roux-Y approach. The duration of the procedure was 220 min, with good tolerance of pneumoperitoneum due to the laparoscopy. Feedings of breast milk began on the third day postoperative, presenting normal colored stools, with normalization of the hepatic test. A 20 months follow-up was without complications.

[Specificity of action of anticancer agents]

Since the first cancer chemotherapy use, efforts have been made in identifying drugs with an antitumor specific action, but cancer is a very complex situation to be cured with a single agent, and to increase drugs selective cytotoxicity new agent combinations, or innovative cellular cycle related schedule, or the use of pro-drugs have been developed. Notwithstanding some relevant improvements in results, chemotherapy remains often a palliative approach. The improved knowledge of the biology of cancer, and of molecular mechanisms and specific targets, has recently modified the approach to various tumors. In particular, the identification of a single and specific genetic alteration in some tumors such as myeloid chronic leukaemia or gastrointestinal stromal tumors (GIST) led to the development of imatinib, a "target" drug with a multikinase inhibitor activity towards the specific genetic alteration; this unique opportunity is not applicable to other tumors, because usually tumors have multiple genetic alterations with very complex molecular pathways. The development of drugs with a multitarget action is probably the best approach to the majority of human cancers, but other possibility are the combination of multiple agents, each with known selective activity towards a specific molecular target, or the choice of a chemotherapic drug in combination with one or more molecularly targeted drugs. The knowledge of the multiple and extremely complex molecular pathways of the neoplastic cells will hopefully drive oncologic science towards a more "exact" science, with the use of "personalized" treatment in each cancer patient.

Biological progression of breast cancer and clinical implications

The classic view of tumor progression is that genetic mutation introduced in differentiated or progenitor cells causes tumors, through the acquisition of advantages for survival, and leading to phenotypic heterogeneity. Another theory (stem cell hypothesis) considers that tumor progression derives from cells within the tumor with stem cell characteristics of self-renewal and multiple differentiation potential. It is still unknown the timing of expression of various biological characteristics of breast cancer during the progression cascade, and the existence of clonal heterogeneity within primary tumor and synchronous or asynchronous distant metastases contributes to treatments failures.