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61.
Biological Invasions - It is widely assumed that spillover of alien parasites to native host species severely impacts naïve populations, ultimately conferring a competitive advantage to...  相似文献   
62.
Locally advanced rectal cancer requires a multidisciplinary management, traditionally based on neo-adjuvant (chemo) radiotherapy, conservative surgery with total mesorectal excision and adjuvant chemotherapy. Despite effective in term of local control, this strategy is linked to a high risk of distant metastasis (up to 30%). In this context, recent published randomized phase III clinical trials have tested the potential benefits with a different sequencing and/or intensification of the standard components of the trimodal therapy.Here, we briefly assess the efficacy and discuss the clinical relevance of total neoadjuvant treatment with a focus on indications and results in the short-course radiotherapy followed by chemotherapy use for this setting of patients. Long term results and additional prospective studies are necessary to more accurately estimate the clinical benefit and further establish the role of total neoadjuvant therapy in locally advanced rectal cancer disease.  相似文献   
63.
In the highly active antiretroviral therapy (HAART) era, hepatocellular carcinoma (HCC) is arising as a common late complication of human immunodeficiency virus (HIV) infection, with a great impact on morbidity and mortality. Though HIV infection alone may not be sufficient to promote hepatocarcinogenesis, the complex interaction of HIV with hepatitis is a main aspect influencing HCC morbidity and mortality.Data about sorafenib effectiveness and safety in HIV-infected patients are limited, particularly for patients who are on HAART. However, in properly selected subgroups, outcomes may be comparable to those of HIV-uninfected patients. Scarce data are available for those other systemic treatments, either tyrosine kinase inhibitors, as well as immune checkpoint inhibitors (ICIs), which have been added to our therapeutic armamentarium. This review examines the influence of HIV infection on HCC development and natural history, summarizes main data on systemic therapies, offers some insight into possible mechanisms of T cell exhaustion and reversal of HIV latency with ICIs and issues about clinical trials enrollment. Nowadays, routine exclusion of HIV-infected patients from clinical trial participation is totally inappropriate, since it leaves a number of patients deprived of life-prolonging therapies.  相似文献   
64.
To test whether the influence of manual activity should be considered when interpreting the results of nerve conduction study (NCS) of the upper limbs performed during work shifts, we evaluated the short-term effect of 90-min repetitive manual work on NCS parameters. Twenty-eight healthy volunteers underwent NCS of the dominant limb at the end of an interview (T0), after a 30-min rest in sitting position (T1) and after performing a standardized 90-min manual task (T2). The task was designed to simulate typical assembly and packing activities. No significant differences were observed for skin temperature (Ts) and NCS parameters between T0 and T1. Significantly (p < 0.001) higher Ts mean values were found at T2 as compared to the previous tests for both females and males. The regression analysis showed an association between temperature variation and nerve conduction velocity values for the median and ulnar nerve at T2 as compared to T1. In females, a reduction of the mean sensory nerve action potential (SNAP) amplitude at T2 was recorded, whereas an opposite trend was observed among males. Manual work is able to influence hand Ts and to modify NCS parameters. SNAP amplitudes changes suggest gender differences in peripheral nerve characteristics that deserve further investigation.  相似文献   
65.
The GPR120 gene (also known as FFAR4 or O3FAR1) encodes for a functional omega-3 fatty acid receptor/sensor that mediates potent insulin sensitizing effects by repressing macrophage-induced tissue inflammation. For its functional role, GPR120 could be considered a potential target gene in animal nutrigenetics. In this work we resequenced the porcine GPR120 gene by high throughput Ion Torrent semiconductor sequencing of amplified fragments obtained from 8 DNA pools derived, on the whole, from 153 pigs of different breeds/populations (two Italian Large White pools, Italian Duroc, Italian Landrace, Casertana, Pietrain, Meishan, and wild boars). Three single nucleotide polymorphisms (SNPs), two synonymous substitutions and one in the putative 3′-untranslated region (g.114765469C > T), were identified and their allele frequencies were estimated by sequencing reads count. The g.114765469C > T SNP was also genotyped by PCR-RFLP confirming estimated frequency in Italian Large White pools. Then, this SNP was analyzed in two Italian Large White cohorts using a selective genotyping approach based on extreme and divergent pigs for back fat thickness (BFT) estimated breeding value (EBV) and average daily gain (ADG) EBV. Significant differences of allele and genotype frequencies distribution was observed between the extreme ADG-EBV groups (P < 0.001) whereas this marker was not associated with BFT-EBV.  相似文献   
66.
Campylobacter have emerged as the most common bacterial food-borne illness in the developed world. The ability to reduce Campylobacter infections in humans is linked to the full comprehension of the principal key aspects of its infection cycle. A microbial diagnostic microarray detecting Campylobacter housekeeping, structural, and virulence associated genes was designed and validated using genomic DNA from reference and field strains of Campylobacter jejuni and coli isolated from human, chicken, and raw milk. This microarray was confirmed to be a powerful diagnostic tool for monitoring emerging Campylobacter pathotypes as well as for epidemiological, environmental, and phylogenetic studies including the evaluation of genome plasticity.  相似文献   
67.
Abstract

The emergence of tumour recurrence and resistance limits the survival rate for most tumour-bearing patients. Only, combination therapies targeting pathways involved in the induction and in the maintenance of cancer growth and progression might potentially result in an enhanced therapeutic efficacy. Herein, we provided a prospective combination treatment that includes suberoylanilide hydroxamic acid (SAHA), a well-known inhibitor of histone deacetylases (HDACs), and SLC-0111, a novel inhibitor of carbonic anhydrase (CA) IX. We proved that HDAC inhibition with SAHA in combination with SLC-0111 affects cell viability and colony forming capability to greater extent than either treatment alone of breast, colorectal and melanoma cancer cells. At the molecular level, this therapeutic regimen resulted in a synergistically increase of histone H4 and p53 acetylation in all tested cell lines. Overall, our findings showed that SAHA and SLC-0111 can be regarded as very attractive combination providing a potential therapeutic strategy against different cancer models.  相似文献   
68.

Introduction

Systemic sclerosis (SSc) is a connective tissue disorder characterized by endothelial cell injury, autoimmunity and fibrosis. The following three fibrillin-1 alterations have been reported in SSc. (1) Fibrillin-1 microfibrils are disorganized in SSc dermis. (2) Fibrillin-1 microfibrils produced by SSc fibroblasts are unstable. (3) Mutations in the FBN1 gene and anti-fibrillin-1 autoantibodies have been reported in SSc. Fibrillin-1 microfibrils, which are abundantly produced by blood and lymphatic microvascular endothelial cells (B-MVECs and Ly-MVECs, respectively), sequester in the extracellular matrix the latent form of the potent profibrotic cytokine transforming growth factor β (TGF-β). In the present study, we evaluated the effects of SSc sera on the deposition of fibrillin-1 and microfibril-associated glycoprotein 1 (MAGP-1) and the expression of focal adhesion molecules by dermal B-MVECs and Ly-MVECs.

Methods

Dermal B-MVECs and Ly-MVECs were challenged with sera from SSc patients who were treatment-naïve or under cyclophosphamide (CYC) treatment and with sera from healthy controls. Fibrillin-1/MAGP-1 synthesis and deposition and the expression of αvβ3 integrin/phosphorylated focal adhesion kinase and vinculin/actin were evaluated by immunofluorescence and quantified by morphometric analysis.

Results

Fibrillin-1 and MAGP-1 colocalized in all experimental conditions, forming a honeycomb pattern in B-MVECs and a dense mesh of short segments in Ly-MVECs. In B-MVECs, fibrillin-1/MAGP-1 production and αvβ3 integrin expression significantly decreased upon challenge with sera from naïve SSc patients compared with healthy controls. Upon challenge of B-MVECs with sera from CYC-treated SSc patients, fibrillin-1/MAGP-1 and αvβ3 integrin levels were comparable to those of cells treated with healthy sera. Ly-MVECs challenged with SSc sera did not differ from those treated with healthy control sera in the expression of any of the molecules assayed.

Conclusions

Because of the critical role of fibrillin-1 in sequestering the latent form of TGF-β in the extracellular matrix, its decreased deposition by B-MVECs challenged with SSc sera might contribute to dermal fibrosis. In SSc, CYC treatment might limit fibrosis through the maintenance of physiologic fibrillin-1 synthesis and deposition by B-MVECs.  相似文献   
69.
External beam radiotherapy (EBRT) is frequently used in the management of prostate cancer (PCa) as definitive, postoperative, or salvage local treatment. Although EBRT plays a central role in the management of PCa, complications remain a troubling by-product. Several studies have demonstrated an association between radiotherapy and elevated risk of acute and late toxicities. A secondary malignancy induced by initial therapy represents one of the most serious complications related to definitive cancer treatment. The radiation-related secondary primary malignancy risk increases with increasing survival time. Transitional cell carcinoma of the bladder is the most frequent secondary primary malignancy occurring after radiotherapy and is described as more aggressive; it may be diagnosed later because some radiation oncologists believe that the hematuria that occurs after prostate EBRT is normal. Some patients treated for localized PCa will subsequently develop invasive bladder cancer requiring surgical intervention. Patients with PCa treated with EBRT should be monitored closely for the presence of bladder cancer.Key words: Bladder cancer, Prostate cancer, Radiotherapy, External beam radiotherapyThe phenomenon of radiation-inducing the carcinogenesis has been well described in literature for decades. The correlation between ionizing radiation and DNA damage has been discussed in several studies.14 Most of these studies evaluated the growth of solid tumors in a large population exposed to moderate to heavy doses of radiation, such as factory workers, patients exposed to a large number of diagnostic radiographic studies, and survivors of atomic and nuclear explosions. 1 The casual effects of radiation exposure with subsequent mutagenesis are quite clear, shown both in vivo and in vitro.2 Previous radiotherapy (RT) for prostate cancer (PCa) may play an important role in the development of secondary primary bladder cancer. This is a fairly uncommon event but a very real entity, of which both urologists and radiation oncologists need to be aware.  相似文献   
70.
Few conventional cytotoxic anticancer therapeutics induce immunogenic cell death (ICD). This means that they induce tumor cells to undergo apoptosis while eliciting the emission of a spatiotemporal-defined combination of damage-associated molecular patterns (DAMPs) decoded by the immune system to activate antitumor immunity effective for long-term therapeutic success. The neurotoxin capsaicin (CPS) can induce both cancer cell apoptosis and immune-mediated tumor regression. In the present study, we investigated whether CPS is capable of eliciting the emission of ICD hallmarks in human bladder cancer cell lines undergoing apoptosis. We demonstrated that CPS induces pre- and early apoptotic cell surface exposure of calreticulin (CRT), HSP90, and HSP70 as well as ATP release. Moreover, CRT exposure was prevented by inhibition of endoplasmic reticulum–Golgi traffic by brefeldin A. Furthermore, high-mobility group box 1, HSP90, and HSP70 were passively released at late apoptotic stages. We provide the first evidence that CPS is an inducer of ICD hallmarks, suggesting CPS as a novel potential immunogenic cytotoxic agent.  相似文献   
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