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471.
Ductal carcinoma in situ (DCIS) of the breast is difficult to remove completely during surgery as it is not palpable and can therefore require re-excision. Real-time visualization of DCIS using near-infrared fluorescent probes could help the surgeon during surgery as well as the pathologist post-operatively to distinguish the tumor from healthy tissue. As hypoxia-induced necrosis is a common phenomenon in DCIS, we investigated the molecular imaging of DCIS using a fluorescent antibody targeting a hypoxia marker, carbonic anhydrase IX (CAIX), in a preclinical mouse model. A monoclonal antibody against human CAIX was fluorescently labeled with the near-infrared dye IRDye800CW and characterized in vitro. An in vivo study was performed in SCID/Beige mice that were orthotopically transplanted with human breast cancer cells mimicking human DCIS (MCF10DCIS) and MCF10DCIS stably expressing CAIX. A clinically approved fluorescence imaging system was used to monitor probe uptake and to determine tumor-to-normal tissue ratios (TNR). Mean in vivo TNR of CAIX-transduced (CAIX+) tumors was 7.5 ± 0.5. Mean in vivo TNR of DCIS tumors with hypoxic areas reached a plateau level at 48 h after injection of 2.1 ± 0.1 (mean ± SEM) compared to 1.7 ± 0.1 in DCIS without hypoxic areas. Mean intra-operative TNR of DCIS tumors with necrotic regions was higher than that of DCIS tumors without necrotic regions 96 h after injection—2.9 ± 0.1 and 1.5 ± 0.1, respectively—while the TNR of CAIX+ tumors was 11.2 ± 1.0. Specific tumor uptake of MabCAIX-IRDye800CW was confirmed by a biodistribution assay, and immunofluorescence imaging on tumor sections showed specific uptake in hypoxic tumor regions, with higher contrast than conventional chromagen-based immunohistochemistry. Molecular fluorescence imaging with MabCAIX-IRDye800CW can be successfully used to detect hypoxic DCIS before and during surgery to facilitate radical resection. Furthermore, it allows for sensitive CAIX-specific immunofluorescence microscopy of tumor sections, thereby introducing the concept of molecular fluorescence pathology.  相似文献   
472.
Gallbladder cancer is a rare, aggressive malignancy that has a poor overall prognosis. Effective treatment consists of early detection and surgical treatment. With the wide spread treatment of gallbladder disease with minimally invasive techniques, the rate of incidental gallbladder cancer has seen an equitable rise along with stage migration towards earlier disease. Although the treatment remains mostly surgical, newer modalities such as regional therapy as well as directed therapy based on molecular medicine has led to improved outcomes in patients with advanced disease. We aim to summarize the management of gallbladder cancer along with the newer developments in this formidable disease process.  相似文献   
473.

Purpose

N 1,N 11-diethylnorspermine (DENSPM), a synthetic analog of the naturally occurring polyamine spermine, can induce polyamine depletion and inhibit tumor cell growth. The objectives of this phase I study were to assess the safety, maximum-tolerated dose (MTD), pharmacokinetics, and preliminary antitumor activity of DENSPM in advanced HCC.

Methods

Patients with measurable advanced HCC, Child-Pugh A or B cirrhosis, CLIP score ≤3, and Karnofsky score ≥60 % were eligible. DENSPM was given as a short intravenous infusion on days 1, 3, 5, 8, 10, and 12 of each 28-day cycle. The starting dose of 30 mg/m2 was escalated at a fixed increment of 15 mg/m2 until the MTD was identified. The plasma pharmacokinetics of DENSPM for the first and last doses given in cycle 1 was characterized.

Results

Thirty-eight patients (male 79 %; median age 61 years; Child-Pugh A 84 %; ≥1 prior systemic therapy 45 %) were enrolled and treated. The most common adverse events (AEs) ≥grade 1 were fatigue (53 %), nausea (34 %), diarrhea (32 %), vomiting (32 %), anemia (29 %), and elevated AST (29 %). The most common grade 3–4 AEs were fatigue/asthenia (13 %), elevated AST (13 %), hyperbilirubinemia (11 %), renal failure (8 %), and hyperglycemia (8 %). The MTD was 75 mg/m2. There were no objective responses, although 7/38 (18 %) patients achieved stable disease for ≥16 weeks. The overall mean (±SD) total body clearance for the initial dose, 66.3 ± 35.9 L/h/m2 (n = 16), was comparable to the clearance in patients with normal to near normal hepatic function. Drug levels in plasma decayed rapidly immediately after the infusion but remained above 10 nM for several days after dosing at the MTD.

Conclusions

N 1,N 11-diethylnorspermine treatment at the MTD of 75 mg/m2, given intravenously every other weekday for two consecutive weeks of each 28-day cycle, was relatively well tolerated in patients with advanced HCC including those with mild-to-moderate liver dysfunction. This administration schedule provided prolonged systemic exposure to potentially effective concentrations of the drug. Stable disease was seen in 18 % of patients receiving DENSPM treatment. Further evaluation of DENSPM monotherapy for advanced HCC does not appear to be justified because of insufficient evidence of clinical benefit in the patients evaluated in this study.  相似文献   
474.
Furan-2-yl-3-pyridin-2-yl-propenone (FPP-3) is a novel synthetic compound and has demonstrated anti-inflammatory activity by inhibiting cyclooxygenase-2 (COX-2). It is widely accepted that reactive oxygen species (ROS) generated by activated inflammatory cells can exacerbate inflammation. In this study, the potential antioxidative efficacy of FPP-3 has been investigated in murine cells. FPP-3 increased the expression of multiple antioxidative enzymes, including NAD(P)H:quinone oxidoreductase 1 (Nqo1), gamma-glutamylcysteine ligase (GCL) and heme oxygenase-1 (HO-1), by facilitating the nuclear translocation of nuclear factor-erythroid 2-p45-related factor 2 (Nrf2). Inducibility of antioxidant proteins such as HO-1 were lost in nrf2-deficient murine fibroblasts. As a result of enhanced cellular antioxidative capacity, elevation of NF-kappaB-driven reporter gene expression by lipopolysaccharide was attenuated by FPP-3 treatment in murine fibroblasts. Furthermore, FPP-3 treatment inhibited UVA-mediated induction of COX-2 in murine keratinocytes. Our current study suggests that FPP-3, which has been developed as a novel COX-2 inhibitor, has antioxidative properties by activating the Nrf2-ARE pathway. The dual function of this compound may provide a better strategy to block/attenuate the inflammation process and to alleviate ROS-associated inflammatory complications.  相似文献   
475.
The aim of this study was to develop a method to generate multi‐organ acellular matrices. Using a foetal sheep model have developed a method of systemic pulsatile perfusion via the umbilical artery which allows for simultaneous multi‐organ decellularization. Twenty sheep foetuses were systemically perfused with Triton X‐100 and sodium dodecyl sulphate. Following completion of the whole‐body decellularization, multiple biopsy samples were taken from different parts of 21 organs to ascertain complete cell component removal in the preserved extracellular matrices. Both the natural and decellularized organs were subjected to several examinations. The samples were obtained from the skin, eye, ear, nose, throat, cardiovascular, respiratory, gastrointestinal, urinary, musculoskeletal, central nervous and peripheral nervous systems. The histological results depicted well‐preserved extracellular matrix (ECM) integrity and intact vascular structures, without any evidence of residual cellular materials, in all decellularized bioscaffolds. Scanning electron microscope (SEM) and biochemical properties remained intact, similar to their age‐matched native counterparts. Preservation of the collagen structure was evaluated by a hydroxyproline assay. Dense organs such as bone and muscle were also completely decellularized, with a preserved ECM structure. Thus, as shown in this study, several organs and different tissues were decellularized using a perfusion‐based method, which has not been previously accomplished. Given the technical challenges that exist for the efficient generation of biological scaffolds, the current results may pave the way for obtaining a variety of decellularized scaffolds from a single donor. In this study, there have been unique responses to the single acellularization protocol in foetuses, which may reflect the homogeneity of tissues and organs in the developing foetal body.  相似文献   
476.
477.
The toxic effects of mercury (Hg) on the histology of the liver of reared spotted scat (Scatophagus argus L.) were investigated. The experiment was conducted to identify the effect of metal concentrations and exposure period on degrees and nature of histological changes in the liver of exposed fish. Selected fish were exposed to 10, 20, and 30?μg?L?1 concentrations of mercury over short-term exposure period. Similar histological changes occurred in the livers of specimens exposed to 10, 20, and 30?μg?L?1 concentrations, indicating a definite toxic response to all metal concentrations. These histological changes included hyalinization, hepatocyte vacuolation, cellular swelling, necrosis, vacuolar degeneration, and congestion of blood vessels. The intensity of these histological changes was, however, influenced by the extent of the exposure period.  相似文献   
478.

Purpose  

Due to the severe problems accompanied with multiple drug resistance (MDR), agents that can induce apoptosis independently of death-suppressing proteins are required. Here, we show that the ferrocene derivative HUNI 068 is active against cancer cells and overcomes different mechanisms of multiple drug resistance (MDR).  相似文献   
479.
Candida infections are common and often fatal in infants and neonates. Anidulafungin has excellent activity against Candida species, but the pharmacokinetics (PK) and safety of the drug in infants and neonates are unknown. The object of our study was to determine the PK and safety of anidulafungin in infants and neonates at risk for invasive candidiasis. Intravenous anidulafungin (1.5?mg/kg/day maintenance dose) was administered to 15 infants and neonates over 3 to 5 days. Plasma samples were collected after the first dose and again after the third to fifth doses. The pharmacokinetic parameters of the drug were determined by noncompartmental analysis. Safety was assessed using National Cancer Institute common toxicity criteria. The study showed that drug exposure levels were similar between neonates and infants; the median areas under the concentration-time curve (range) was 75 (30-109) μg·h/ml and 98 (55-278) μg·h/ml (P = 0.12) for neonates and infants, respectively. No drug-related serious adverse events were observed. The study results indicate that neonates and infants receiving 1.5?mg/kg/day have anidulafungin exposure levels similar to those in children receiving similar weight-based dosing and in adult patients receiving 100?mg/day.  相似文献   
480.
Stress has been shown to interact with genetic vulnerability in pathogenesis of psychiatric disorders. Here we investigated the outcome of interaction between genetic vulnerability and early-life stress, by employing a rodent model that combines an inherited trait of vulnerability in Flinders Sensitive Line (FSL) rats, with early-life stress (maternal separation). Basal differences in synaptic signaling between FSL rats and their controls were studied, as well as the consequences of early-life stress in adulthood, and their response to chronic antidepressant treatment (escitalopram). FSL rats showed basal differences in the activation of synapsin I and Erk1/2, as well as in αCaM kinase II/syntaxin-1 and αCaM kinase II/NMDA-receptor interactions in purified hippocampal synaptosomes. In addition, FSL rats displayed a blunted response of Erk-MAP kinases and other differences in the outcome of early-life stress in adulthood. Escitalopram treatment restored some but not all alterations observed in FSL rats after early-life stress. The marked alterations found in key regulators of presynaptic release/neurotransmission in the basal FSL rats, and as a result of early-life stress, suggest synaptic dysfunction. These results show that early gene-environment interaction may cause life-long synaptic changes affecting the course of depressive-like behavior and response to drugs.  相似文献   
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