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781.
Cancer is a leading cause of death worldwide. Nowadays, the therapies are inadequate and spur demand for improved technologies. Rapid growth in nanotechnology and novel nanomedicine products represents an opportunity to achieve sophisticated targeting strategies and multi-functionality. Nanomedicine is increasingly used to develop new cancer diagnosis and treatment methods since this technology can modulate the biodistribution and the target site accumulation of chemotherapeutic drugs, thereby reducing their toxicity. Cancer nanotechnology and cancer immunotherapy are two parallel themes that have emerged over the last few decades while searching for a cure for cancer. Immunotherapy is revolutionizing cancer treatment, as it can achieve unprecedented responses in advanced-stage patients, including complete cures and long-term survival. A deeper understanding of the human immune system allows the establishment of combination regimens in which immunotherapy is combined with other treatment modalities (as in the case of the nanodrug Ferumoxytol). Furthermore, the combination of gene therapy approaches with nanotechnology that aims to silence or express cancer-relevant genes via one-time treatment is gradually progressing from bench to bedside. The most common example includes lipid-based nanoparticles that target VEGF-Α and KRAS pathways. This review focuses on nanoparticle-based platforms utilized in recent advances aiming to increase the efficacy of currently available cancer therapies. The insights provided and the evidence obtained in this paper indicate a bright future ahead for immuno-oncology applications of engineering nanomedicines.  相似文献   
782.
783.
In the present study, the application and evaluation of Girard's Reagent T (GRT) derivatization for the simultaneous detection and significantly important identification of different phase II methenolone and mesterolone metabolites by LC-MS/(MS) are presented. For the LC-MS analysis of target analytes two complementary isolation methods were developed; a derivatization and shoot method in which native urine is diluted with derivatization reagent and is injected directly to LC-MS and a liquid–liquid extraction method, using ethyl acetate at pH 4.5, for the effective isolation of both sulfate and glucuronide metabolites of the named steroids as well as of their free counterparts. For the evaluation of the proposed protocols, urine samples from methenolone and mesterolone excretion studies were analyzed against at least one sample from a different excretion study. Retention times, along with product ion ratios, were evaluated according to the WADA TD2021IDCR requirements, in order to determine maximum detection and identification time windows for each metabolite. Established identification windows obtained after LC-MS/(MS) analysis were further compared with those obtained after GC-MS/(MS) analysis of the same samples from the same excretion studies, for the most common analytes monitored by GC-MS/(MS). Full validation was performed for the developed derivatization and shoot method for the identification of methenolone metabolite, 3α-hydroxy-1-methylen-5α-androstan-17-one-3-glucuronide (mth3). Overall, the GRT derivatization presented herein offers a tool for the simultaneous sensitive detection of free, intact glucuronide and sulfate metabolites by LC-MS/(MS) that enhance significantly the detection and identification time windows of specific methenolone and mesterolone metabolites for doping control analysis.  相似文献   
784.
George Papatheodoridis  Konstantinos Mimidis  Spilios Manolakopoulos  Christos Triantos  Ioannis Vlachogiannakos  Christos Veretanos  Melanie Deutsch  Stylianos Karatapanis  Ioannis Goulis  Ioannis Elefsiniotis  Evangelos Cholongitas  Vassilios Sevastianos  Dimitrios Christodoulou  Dimitrios Samonakis  Emanuel Manesis  Andreas Kapatais  Nikolaos Papadopoulos  Panagiota Ioannidou  Georgios Germanidis  George Giannoulis  Dimitra Lakiotaki  Dionysios Kogias  Ηarikleia Kranidioti  Konstantinos Zisimopoulos  Maria Mela  George Kontos  Paraskevi Fytili  Chrysanthi Manolaka  Polyxeni Agorastou  Spyridon I. Pantzios  Margarita Papatheodoridi  Dimitrios Karagiannakis  Eleni Geladari  Nikolaos Psychos  Kalliopi Zachou  Anna Chalkidou  Anastasia Spanoudaki  Konstantinos Thomopoulos  George Dalekos 《Liver international》2023,43(9):1879-1889

Background and Aims

Hepatitis D virus (HDV) underdiagnosis remains common. We assessed the HDV screening and prevalence rates in HBsAg-positive patients seen at tertiary liver centres throughout Greece as well as factors affecting HDV diagnosis.

Methods

All adult HBsAg-positive patients seen within the last 5 years were included. Non-screened patients who visited or could be recalled to the clinics over a 6-month period were prospectively tested for anti-HDV.

Results

Of 5079 HBsAg-positive patients, 53% had anti-HDV screening (41% before and 12% after study initiation). Pre-study (8%–88%) and total screening rates (14%–100%) varied widely among centres. Screening rates were associated with older age, known risk group, elevated ALT, centre location and size and period of first visit. Anti-HDV prevalence was 5.8% without significant difference in patients screened before (6.1%) or after study initiation (4.7%, p = 0.240). Anti-HDV positivity was associated with younger age, parenteral drug use, born abroad, advanced liver disease and centre location. Overall, HDV RNA detectability rate was 71.6% being more frequent in anti-HDV-positive patients with elevated ALT, advanced liver disease and hepatitis B therapy.

Conclusions

Anti-HDV screening rates and recall capabilities vary widely among Greek liver clinics being higher in HBsAg-positive patients of known risk group with active/advanced liver disease seen at smaller centres, while non-medical factors are also important. Anti-HDV prevalence varies throughout Greece being higher in patients born abroad with younger age, parenteral drug use and advanced liver disease. Viremia is more frequently but not exclusively detected in anti-HDV-positive patients with elevated ALT and advanced liver disease.  相似文献   
785.
Neprilysin (NEP) is a transmembrane zinc-dependent metalloproteinase that inactivates various peptide hormones including glucagon-like peptide 1 (GLP-1). NEP inhibitors may be effective in the management of type 2 diabetes mellitus (T2DM) by increasing the circulating level of GLP-1. However, acute-effect NEP inhibitors may lead to detrimental effects by increasing blood glucose independent of GLP-1. These findings suggest a controversial point regarding the potential role of NEP inhibitors on glucose homeostasis in T2DM patients. Therefore, this perspective aimed to clarify the controversial points concerning the role of NEP inhibitors on glucose homeostasis in T2DM. NEP inhibitors may lead to beneficial effects by inhibition of NEP, which is involved in the impairment of glucose homeostasis through modulation of insulin resistance. NEP increases dipeptidyl peptidase-4 (DPP4) activity and contributes to increasing active GLP-1 proteolysis so NEP inhibitors may improve glycemic control through increasing endogenous GLP-1 activity and reduction of DPP4 activity. Thus, NEP inhibitors could be effective alone or in combination with antidiabetic agents in treating T2DM patients. However, long-term and short-term effects of NEP inhibitors may lead to a detrimental effect on insulin sensitivity and glucose homeostasis through different mechanisms including augmentation of substrates and pancreatic amyloid deposition. These findings are confirmed in animal but not in humans. In conclusion, NEP inhibitors produce beneficial rather than detrimental effects on glucose homeostasis and insulin sensitivity in humans though most of the detrimental effects of NEP inhibitors are confirmed in animal studies.  相似文献   
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