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[en] Multiple colorectal adenomas (MCRAs) syndrome is a genetic syndrome characterized by multiple colorectal polyps. Patients usually present late in late fourth or fifth decade of life. They have a high risk for developing malignancy. We here present such case of a 61-year-old man with MCRAs who developed malignant degeneration of multiple colorectal polyps, which was demonstrated on 18F-fluorodeoxyglucose positron emission tomography–computed tomography.
[en] Exposure to environmental pollutants results in out-of-balance of vascular homeostasis. Endothelial dysfunction leads to a disruption of the endothelial permeability characteristics, associated with cardiovascular diseases. We previously reported that endosulfan could cause endothelial dysfunction, but the role of endosulfan in permeability of endothelial cells has been unexplored. To elucidate molecular mechanism of endosulfan-induced changes in endothelial permeability, human umbilical vein endothelial cells (HUVECs) were exposed to endosulfan, followed by endothelial permeability analysis. The results showed that permeability of HUVECs was enhanced at 48 h after exposure to endosulfan in a dose-dependent manner. Immunofluorescence analysis demonstrated the disruptions of actin cytoskeleton and focal adhesion in endosulfan-exposed cells. Endosulfan activated MMP3/LAMC1/FAK signaling pathway, and downregulated ROCK and PXN in transcellular pathway. Endosulfan affected adherens junctions via E-cadherin and β-catenin, and impaired gap junctions through downregulation of Cx43 in paracellular pathway. We predicted four closely related human cardiovascular diseases in Nextbio, including shock, coronary arteriosclerosis, disorder of cardiac function and hypertensive disorder in relation to endosulfan exposure. Some genes such as ROCK2 and PXN were predicted to be key genes in these diseases. These findings suggest that endosulfan increased endothelial permeability by paracellular and transcellular pathways, implicating the potential correlation between endosulfan and cardiovascular diseases. - Highlights: • Endosulfan enhances endothelial permeability in HUVECs. • Endosulfan disrupts actin cytoskeleton and focal adhesion. • Endosulfan affects adherens junctions and impaired gap junctions. • Cardiovascular diseases are predicted to correlate with endosulfan exposure.
[en] To assess the effects of incorporation of a CF2 group into the side chain of a 2-nitroimidazole derivative, the authors evaluated the in vitro and in vivo radiosensitizing activities of KU-2285 (a 2-nitroimidazole derivative with an N1-substituent of -CH2CF2CONH(CH2)nOH) and its related compounds in comparison with those of comparable nonfluorinated compounds. The pharmacokinetics of these compounds in murine tumors was also tested. KU-2285, KU-3202, and KU-3207 are fluorinated 2-nitroimidazole derivative compounds with similar structures. Etanidazole (a 2-nitroimidazole derivative with an N1-substituent of -CH2CONH(CH2)nOH) and its related compounds, KU-3205 and KU-3206 were also tested. The in vivo radiosensitizing activities of each compound for hypoxic cells was evaluated with a standard colony formation method. The in vivo radiosensitizing activities of these compounds were tested in female C3H/He mice bearing SCCVII tumors using an in vivo/in vitro clonogenic assay. The pharmacokinetic studies were performed in C3H/He mice bearing the SCCVII tumor. Samples were analyzed by reversed-phase high-performance liquid chromatography. The in vitro radiosensitizing activities of fluorinated 2-nitroimidazoles were higher than those of the nonfluorinated compounds. Although the in vivo radiosensitizing activity of KU-2285 was higher than that of etanidazole, other fluorinated 2-nitroimidazoles showed less radiosensitizing activity than the comparable nonfluorinated compounds. The compound was eliminated from serum more rapidly with the increase in the number of CH2 group in the side chain of the compound in each series. Although the in vitro sensitizing activity of the fluorinated compounds was higher than that of the comparable nonfluorinated compounds, the in vivo radiosensitizing activity of all fluorinated compounds but KU-2285 was lower than that of comparable etanidazole group compounds. 8 refs., 2 figs., 1 tab
[en] Highlights: • Crucial influence of open-closed skeletal transitions on the electronic properties of fullerene was demonstrated. • Electrochemically promoted switching of electronic properties based on disruption of the conjugated 62π-electron system into the isolated 32 and 28π-electron fragments upon closing the [5,6]-bond in question. • Regioselective near-equatorial cycloproponation of trifluoromethylfullerene Cs-C70(CF3)8 was elaborated. • More compact alternatives promising molecular switching capabilities can be found within the family of pyramidalized polyenes. - Abstract: Despite trifluoromethylfullerene Cs-C70(CF3)8 has a multitude of available reaction sites, [2 + 1] cycloaddition of CX2 moieties (X = F and p-MeOC6H4) proceeds regioselectively at a particular [5,6]-bond. Depending on the nature of X, the resulting derivative can be either [5,6]-open (i.e., the said C−C bond is cleaved) or [5,6]-closed, and this structural detail, seemingly insignificant for a molecule that large, brings about a remarkable 0.6 eV difference in the electron affinity, as revealed by electrochemical studies. Synthesis, structural and electrochemical elucidation of the C70(CF3)8(CX2) compounds are discussed, as well as electrochemically promoted switching of the electronic properties based on disruption of the conjugated 62π-electron system into the isolated 32 and 28π-electron fragments upon closing the [5,6]-bond.
[en] Primitive neuroectodermal tumor is a malignant small round cell tumor of presumed neural crest origin, usually affecting the bony structures of the nasal cavity and its clinical and radiological features may be confused with those of infection and malignancy. I report a case with primitive neuroectodermal tumor of the nasal cavity showing increased tracer uptake on 18F-fluorodeoxyglucose positron emission tomography-computed tomography mimicking an another primary malignancy in a 17-year-old boy.
[en] A rare acquired demyelinating lesion of the pons central pontine myelinolysis (CPM) typically occurs after rapid correction of hyponatremia. There is disruption of blood–brain barrier due to osmotic stress allowing access for inflammatory mediators in extravascular brain tissue, which most likely attracts glial cells of the brain, attracts macrophages, and activates astrocytes. We present a case of female with a known history of inflammatory bowel disease who presented with altered sensorium and hyponatremia. Fluorine-18-fuorodeoxyglucose (F-18-FDG) positron emission tomography/computed tomography (PET/CT) was performed which showed localized FDG uptake in the pons, consistent with the CPM findings observed on magnetic resonance imaging. Pontine uptake in F-18-FDG PET CT in hyponatremic patients who were clinically deteriotating even after correction of hyponatremic status aids for the diagnosis of CPM.
[en] We present the case of a-55-year-old female patient who presented with dry cough. High-resolution computed tomography chest revealed multiple nodules in both lungs. 18F-fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT) was done to look for the unknown primary. It showed hypermetabolic bilateral lung nodules, subcutaneous nodules involving lower limbs, an intramuscular nodule, enlarged paratracheal, and right axillary nodes. There was no primary tumor seen. The biopsy of subcutaneous nodule revealed panniculitis with the foreign body granuloma. Follow-up scans after 6 and 9 months showed spontaneous resolution of all lesions except for few right axillary nodes. There was no active treatment given, and the patient remains asymptomatic on follow-up. Here, PET/CT played a role in excluding a primary tumor, guiding the biopsy, and follow-up.
[en] Testicular metastasis from gastroesophageal junction (GEJ) adenocarcinoma is a very rare condition. A 57-year-old male with a history of neoadjuvant chemotherapy and surgery for HER-2-positive GEJ adenocarcinoma underwent a follow-up 18F-fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT). It revealed multiple metastases including bilateral testicular and L4 laminar metastasis. The patient received multiple chemotherapies, but follow-up PET/CT showed interval progression of disease. Here, we present a case highlighting one of the unusual sites of metastasis from GEJ cancer, role of PET/CT as a surveillance tool in such patients, and the importance of radiologists to be aware of such uncommon sites of metastasis to avoid interpretative errors.
[en] Because reoxygenation of solid tumors after irradiation with a hypoxic cell sensitizer has never previously been investigated, the authors assessed the reoxygenation in SCCVII tumors after treatment with KU-2285 plus single or fractionated irradiation. KU-2285 (100 mg/kg) was injected intraperitoneally into C3H mice bearing 1-cm SCCVII tumors at 30 min before a single dose of 12 Gy or three fractions of 5 Gy at 12 h intervals. Changes of the hypoxic fraction (HF) were then evaluated by the paired survival curve method. Since the radiosensitizing effect of KU-2285 was relatively persistent, the HF was only evaluable after 6 h of irradiation. The HF of untreated SCCVII tumors was 9.1%. After treatment with KU-2285 and 12 Gy, the HF was 25% at 6 h, 32% at 12 h, 24% at 24 h, and 7.6% at 72 h. The HF was lower at 6 h than that after radiation alone, but was similar at later periods. After three fractions of 5 Gy with or without KU-2285, the HF was 33% at 6 h in both groups, while it was 12% and 13% at 24 h for tumors pretreated with KU-2285 and those receiving radiation alone, respectively. However, a sensitizing effect of KU-2285 was indicated by the downward shift of the survival curves for tumors irradiated after exposure to this agent. Reoxygenation occurred quite efficiently in tumors receiving KU-2285 and 12 Gy. After fractionated irradiation, however, reoxygenation was similar in the KU-2285-pretreatment and irradiation alone groups. 11 refs., 4 figs