3,320 research outputs found
Visualization of DNA G-quadruplexes in herpes simplex virus 1-infected cells
We have previously shown that clusters of guanine quadruplex (G4) structures can form in the human herpes simplex-1 (HSV-1) genome. Here we used immunofluorescence and immune-electron microscopy with a G4-specific monoclonal antibody to visualize G4 structures in HSV-1 infected cells. We found that G4 formation and localization within the cells was virus cycle dependent: viral G4s peaked at the time of viral DNA replication in the cell nucleus, moved to the nuclear membrane at the time of virus nuclear egress and were later found in HSV-1 immature virions released from the cell nucleus. Colocalization of G4s with ICP8, a viral DNA processing protein, was observed in viral replication compartments. G4s were lost upon treatment with DNAse and inhibitors of HSV-1 DNA replication. The notable increase in G4s upon HSV-1 infection suggests a key role of these structures in the HSV-1 biology and indicates new targets to control both the lytic and latent infection
Techno-economic analysis of hydrogen production using biomass gasification. A small scale power plant study
Hydrogen has the potential to be a clean alternative to the fossil fuels currently used. This is especially true if hydrogen is
manufactured from renewable resources such as biomass. However, hydrogen from biomass faces techno and economic challenges
especially in the small size required for the decentralized hydrogen production. In this purpose, a techno economic analysis was
carried out on small scale (100kWth) system. The plant is mainly composed of gasifier (double bubbling fluidized bed reactor)
coupled with a Portable Purification Unit (PPS: catalytic filter candles, Water Gas Shift and Pressure Swing Absorption). This
work focuses on system costs to identify barriers to the development of this technology. A sensitivity analysis was conducted to
study hydrogen production cost as a function of capital cost, operating cost and hydrogen production efficiency. The results
showed that although efficiency of the production system is the main factor to fall production cost, it cannot be able to reduce costs
to favorable level alone. In other words, PPS cost recognized as the major cost is requisite to go down. Therefore, the 50%
reduction of PPS cost and the variation of steam to biomass from 1 to 1.5 allow the special cost to fluctuate between 12.75-9.5
€/kg
Brain stimulation as a therapeutic tool in Amyotrophic Lateral Sclerosis: current status and interaction with mechanisms of altered cortical excitability
In the last 20 years, several modalities of neuromodulation, mainly based on non-invasive brain stimulation (NIBS) techniques, have been tested as a non-pharmacological therapeutic approach to slow disease progression in amyotrophic lateral sclerosis (ALS). In both sporadic and familial ALS cases, neurophysiological studies point to motor cortical hyperexcitability as a possible priming factor in neurodegeneration, likely related to dysfunction of both excitatory and inhibitory mechanisms. A trans-synaptic anterograde mechanism of excitotoxicity is thus postulated, causing upper and lower motor neuron degeneration. Specifically, motor neuron hyperexcitability and hyperactivity are attributed to intrinsic cell abnormalities related to altered ion homeostasis and to impaired glutamate and gamma aminobutyric acid gamma-aminobutyric acid (GABA) signaling. Several neuropathological mechanisms support excitatory and synaptic dysfunction in ALS; additionally, hyperexcitability seems to drive DNA-binding protein 43-kDA (TDP-43) pathology, through the upregulation of unusual isoforms directly contributing to ASL pathophysiology. Corticospinal excitability can be suppressed or enhanced using NIBS techniques, namely, repetitive transcranial magnetic stimulation (rTMS) and transcranial direct current stimulation (tDCS), as well as invasive brain and spinal stimulation. Experimental evidence supports the hypothesis that the after-effects of NIBS are mediated by long-term potentiation (LTP)-/long-term depression (LTD)-like mechanisms of modulation of synaptic activity, with different biological and physiological mechanisms underlying the effects of tDCS and rTMS and, possibly, of different rTMS protocols. This potential has led to several small trials testing different stimulation interventions to antagonize excitotoxicity in ALS. Overall, these studies suggest a possible efficacy of neuromodulation in determining a slight reduction of disease progression, related to the type, duration, and frequency of treatment, but current evidence remains preliminary. Main limitations are the small number and heterogeneity of recruited patients, the limited "dosage" of brain stimulation that can be delivered in the hospital setting, the lack of a sufficient knowledge on the excitatory and inhibitory mechanisms targeted by specific stimulation interventions, and the persistent uncertainty on the key pathophysiological processes leading to motor neuron loss. The present review article provides an update on the state of the art of neuromodulation in ALS and a critical appraisal of the rationale for the application/optimization of brain stimulation interventions, in the light of their interaction with ALS pathophysiological mechanisms
Sustainable refurbishment method for industrialized public residential buildings in the mediterranean climate
Stigmatisation and resilience in inflammatory bowel disease
© 2019, The Author(s). Inflammatory bowel disease, which includes Crohn’s disease and ulcerative colitis, is an immune-mediated, chronic relapsing disorder characterised by severe gastrointestinal symptoms that dramatically impair patients’ quality of life, affecting psychological, physical, sexual, and social functions. As a consequence, patients suffering from this condition may perceive social stigmatisation, which is the identification of negative attributes that distinguish a person as different and worthy of separation from the group. Stigmatisation has been widely studied in different chronic conditions, especially in mental illnesses and HIV-infected patients. There is a growing interest also for patients with inflammatory bowel disease, in which the possibility of disease flare and surgery-related issues seem to be the most important factors determining stigmatisation. Conversely, resilience represents the quality that allows one to adopt a positive attitude and good adjustments despite adverse life events. Likewise, resilience has been studied in different populations, age groups, and chronic conditions, especially mental illnesses and cancer, but little is known about this issue in patients with inflammatory bowel disease, even if this could be an interesting area of research. Resilience can be strengthened through dedicated interventions that could potentially improve the ability to cope with the disease. In this paper, we focus on the current knowledge of stigmatisation and resilience in patients with inflammatory bowel disease
Trastuzumab and Gemcitabine in Pretreated HER2 Overexpressing Metastatic Breast Cancer Patients: Retrospective Analysis of Our Series
Trastuzumab-based regimes improved clinical outcome in women with overexpressing HER2 metastatic breast cancer, mainly due to the availability of different combination therapies, clinically active and well tolerated. In this study we retrospectively evaluated clinical activity and toxicity of trastuzuamb plus gemcitabine regimen in heavily pretreated HER2 positive metastatic breast cancer patients. Although the observed population was heavily pretreated, the evaluated regimen was notably effective in terms of response rate, time to progression and survival, with very mild toxicity.
These data suggest that in over expressing HER2 metastatic breast cancer patients, sequential trastuzumab based chemotherapeutic regimens can achieve good response rate with prolonged TTP in responding patients, even after other target therapy such as lapatinib based combinations
Clinical predictive factors of pathologic complete response in locally advanced rectal cancer
Background: Predictive factors of pathologic complete response (pCR) after neoadjuvant chemoradiotherapy (nCRT) in locally advanced rectal cancer (LARC) are still not identified. The purpose of this study was to define them.
Materials and Methods: Data from consecutive LARC patients treated between January 2008 and June 2014 at our Institution were included in the analysis. All patients were treated with a long course of nCRT. Demographics, initial diagnosis and tumor extension details, as well as treatment modalities characteristics were included in the univariate and logistic regression analysis.
Results: In total 99 patients received nCRT, of whom 23 patients (23.2%) achieved pCR. Patients with and without pCR were similar in term of age, sex, comobidities, BMI and tumor characteristics. Multivariate logistic regression indicated that pre-treatment tumor size <= 5 cm was a significant predictor for pCR (p = 0.035), whereas clinical N stage only showed a positive trend (p = 0.084).
Conclusions: Tumor size at diagnosis could be used to predict pCR, and thus to individualize therapy in LARC patients management. Validation in other studies is needed
Whole-exome analysis in osteosarcoma to identify a personalized therapy
Osteosarcoma is the most common pediatric primary non-hematopoietic bone
tumor. Survival of these young patients is related to the response to chemotherapy and
development of metastases. Despite many advances in cancer research, chemotherapy
regimens for osteosarcoma are still based on non-selective cytotoxic drugs. It is essential
to investigate new specific molecular therapies for osteosarcoma to increase the survival
rate of these patients. We performed exomic sequence analyses of 8 diagnostic biopsies
of patients with conventional high grade osteosarcoma to advance our understanding
of their genetic underpinnings and to correlate the genetic alteration with the clinical
and pathological features of each patient to identify a personalized therapy.
We identified 18,275 somatic variations in 8,247 genes and we found three
mutated genes in 7/8 (87%) samples (KIF1B, NEB and KMT2C). KMT2C showed the
highest number of variations; it is an important component of a histone H3 lysine 4
methyltransferase complex and it is one of the histone modifiers previously implicated
in carcinogenesis, never studied in osteosarcoma. Moreover, we found a group of 15
genes that showed variations only in patients that did not respond to therapy and
developed metastasis and some of these genes are involved in carcinogenesis and
tumor progression in other tumors.
These data could offer the opportunity to get a key molecular target to identify
possible new strategies for early diagnosis and new therapeutic approaches for
osteosarcoma and to provide a tailored treatment for each patient based on their
genetic profile
Psychological adjustment and heart rate variability in ovarian cancer survivors
Introduction: Body image, posttraumatic growth, quality of life, coping, and social support are relevant
concepts to ovarian cancer survivors. This study aimed to examine the associations among these
concepts as well as their relationships with heart rate variability (HRV), which is an index of vagal tone.
Methods: an exploratory and correlational study was conducted on 25 ovarian cancer survivors. We
used self-report measures to assess psychological variables. HRV parameters recorded for this study
were analyzed in the time domain and in the frequency domain. Spearman correlations were performed.
Results: Positive attitude coping strategy was associated with psychological and physical distress related
to problems of appearance (Rho = -.57, p < .01), emotional functioning (Rho = .53, p < .01), and
global health (Rho = .47, p < .05). Problem solving coping strategy was correlated with a higher
posttraumatic growth, namely greater personal strength (Rho = .44, p < .05) and better relationships
with others (Rho = .40, p < .05). Seeking social support was associated with growth in relationships
with others (Rho = .40, p < .05). Higher HRV parameters were associated with higher physical
functioning (SDNN: Rho = .59, p < .01; RMSSD: Rho = .54; p < .01; pNN50: Rho = .56, p < .01;
HF: Rho = .58, p < .01). The ratio of low-frequency to high-frequency power (LF/HF) was negatively
associated with posttraumatic growth (i.e., personal strength: Rho = .51, p < .05; new possibilities: Rho
= -.54, p < .01).
Discussion: Positive attitude and problem solving coping strategies may facilitate psychological
adjustment to ovarian cancer. The strong association between markers of vagal tone and physical
functioning offers insights on the possible role of vagus nerve in ovarian cancer survivors. These
findings should be further investigated by future studies with larger samples and longitudinal designs
Plasma from pre-pubertal obese children impairs insulin stimulated Nitric Oxide (NO) bioavailability in endothelial cells: Role of ER stress.
Childhood obesity is commonly associated with early signs of endothelial dysfunction, characterized by impairment of insulin signaling and vascular Nitric Oxide (NO) availability. However, the underlying mechanisms remain to be established. Hence, we tested the hypothesis that endothelial insulin-stimulated NO production and availability was impaired and related to Endoplasmic Reticulum (ER) in human umbilical vein endothelial cells (HUVECs) cultured with plasma obtained from pre-pubertal obese (OB) children. OB children (N = 28, age: 8.8 ± 2.2; BMI z-score: 2.15 ± 0.39) showed impaired fasting glucose, insulin and HOMA-IR than normal weight children (CTRL; N = 28, age: 8.8 ± 1.7; BMI z-score: 0.17 ± 0.96). The in vitro experiments showed that OB-plasma significantly impaired endothelial insulin-stimulated NO production and bioavailability compared to CTRL-plasma. In parallel, in HUVECs OB-plasma increased GRP78 and activated PERK, eIF2α, IkBα and ATF6 (all ER stress markers). Moreover, OB-plasma increased NF-κB activation and its nuclear translocation. Notably, all these effects proved to be significantly restored by using PBA and TUDCA, known ER stress inhibitors. Our study demonstrate for the first time that plasma from obese children is able to induce in vitro endothelial insulin resistance, which is characterized by reduced insulin-stimulated NO production and bioavailability, endothelial ER stress and increased NF-κB activation
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