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BackgroundFocal liver lesions with spindle cell morphology are rare in the daily practice of pathology. The differential diagnosis is broad, including both tumors and tumor-like lesions. Initial radiologic assessment is sometimes inaccurate. Histopathology is needed to arrive at the correct diagnosis. This study analyzed discrepancies between histopathology and radiologic findings of focal liver lesions with spindle cell morphology.MethodsA six-year retrospective analysis was conducted at a tertiary hospital in Thailand. All focal liver lesions with spindle cell morphology were retrieved. Clinicopathologic features of these cases were analyzed. The pathological diagnosis was rendered primarily based on routine histopathology, using other ancillary studies as an adjunct.Results287 biopsies and 151 resection specimens with focal liver lesions were identified. In 12 (2.7%) cases, tumors or tumor-like lesions with spindle cell morphology were retrieved. A total of five cases had discrepancies between histopathology and radiologic findings. These lesions encompassed primary liver tumors (EBV-associated smooth muscle tumor and leiomyosarcoma); metastatic tumors (gastrointestinal stromal tumor, small cell neuroendocrine carcinoma); and a tumor-like lesion (endometriosis). Several morphologic findings (i.e., cytologic grades, dense and loose areas, intratumoral lymphocytes, distinct perinuclear vacuoles, and hemosiderin) are important clues to diagnose these spindle cell lesions.ConclusionsPathologists play a critical role in diagnosing focal liver lesions with spindle cell morphology, particularly those with limited clinical data at the initial presentation. A thorough evaluation of histomorphology on routine hematoxylin and eosin-stained slides is essential for correct diagnosis.  相似文献   
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AimGenomic-based ancillary assays including immunohistochemistry (IHC) for BRCA-1 associated protein-1 (BAP1) and methylthioadenosine phosphorylase (MTAP), and fluorescence in situ hybridization (FISH) for CDKN2A are effective for differentiating pleural mesothelioma (PM) from reactive mesothelial proliferations. We previously reported a combination of MTAP and BAP1 IHC effectively distinguishes sarcomatoid PM from fibrous pleuritis (FP). Nevertheless, cases of sarcomatoid PM with desmoplastic features (desmoPM) are encountered where the IHC assessment is unclear.Methods and resultsWe evaluated assessment of MTAP IHC, BAP1 IHC, and CDKN2A FISH in 20 desmoPM compared to 24 FP. MTAP and BAP1 IHC could not be assessed in 11 (55 %) and 10 (50 %) cases, respectively, due to loss or faint immunoreactivity of internal positive control cells, while CDKN2A FISH could be evaluated in all cases. The sensitivities for MTAP loss, BAP1 loss, and CDKN2A homozygous deletion in desmoPM were 40 %, 10 %, and 100 %. A combination of MTAP loss and BAP1 loss yielded 45 % of sensitivity.ConclusionsMTAP IHC is a useful surrogate diagnostic marker in differentiating ordinary sarcomatoid PM from FP, but its effectiveness is limited in desmoPM. CDKN2A FISH is the most effective diagnostic assays with 100 % sensitivity and specificity in discriminating desmoPM from FP in the facilities where the FISH assay is available.  相似文献   
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《Clinical therapeutics》2022,44(7):1012-1025
Statins, or 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors, are the mainstay of treatment for hypercholesterolemia as they effectively reduce LDL-C levels and risk of atherosclerotic cardiovascular disease. Apart from hyperglycemia, dyslipidemia and HDL dysfunction are known risk factors for neuropathy in people with obesity and diabetes. Although there are case reports of statin-induced neuropathy, ad hoc analyses of clinical trials and observational studies have shown that statins may improve peripheral neuropathy. However, large randomized controlled trials and meta-analyses of cardiovascular outcome trials with statins and other lipid-lowering drugs have not reported on neuropathy outcomes. Because neuropathy was not a prespecified outcome in major cardiovascular trials, one cannot conclude whether statins or other lipid-lowering therapies increase or decrease the risk of neuropathy. The aim of this review was to assess if statins have beneficial or detrimental effects on neuropathy and whether there is a need for large well-powered interventional studies using objective neuropathy end points.  相似文献   
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Although methadone is effective in the management of acute pain, the complexity of its absorption-distribution-metabolism-excretion profile limits its use as an opioid of choice for perioperative analgesia. Because deuteration is known to improve the pharmacokinetic, pharmacodynamic and toxicological properties of some drugs, here we characterized the single dose pharmacokinetic properties and post-operative analgesic efficacy of d9-methadone.The pharmacokinetic profiles of d9-methadone and methadone administered intravenously to CD-1 male mice revealed that deuteration leads to a 5.7- and 4.4-fold increase in the area under the time-concentration curve and maximum concentration in plasma, respectively, as well as reduction in clearance (0.9 ± 0.3 L/h/kg vs 4.7 ± 0.8 L/h/kg). The lower brain-to-plasma ratio of d9-methadone compared to that of methadone (0.35 ± 0.12 vs 2.05 ± 0.62) suggested that deuteration decreases the transfer of the drug across the blood-brain barrier. The estimated LD50 value for a single intravenous dose of d9-methadone was 2.1-fold higher than that for methadone. Moreover, d9-methadone outperformed methadone in the efficacy against postoperative pain by primarily activating peripheral opioid receptors. Collectively, these data suggest that the replacement of three hydrogen atoms in three methyl groups of methadone altered its pharmacokinetic properties, improved safety, and enhanced its analgesic efficacy.  相似文献   
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《Vaccine》2022,40(32):4440-4452
Coronavirus disease 2019 (COVID-19) is an acute respiratory illness caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The prevention of SARS-CoV-2 transmission has become a global priority. Previously, we showed that a protein subunit vaccine that was developed based on the fusion of the SARS-CoV-2 receptor-binding domain (RBD) to the Fc portion of human IgG1 (RBD-Fc), produced in Nicotiana benthamiana, and adjuvanted with alum, namely, Baiya SARS-CoV-2 Vax 1, induced potent immunological responses in both mice and cynomolgus monkeys. Hence, this study evaluated the protective efficacy, safety, and toxicity of Baiya SARS-CoV-2 Vax 1 in K18-hACE2 mice, monkeys and Wistar rats. Two doses of vaccine were administered three weeks apart on Days 0 and 21. The administration of the vaccine to K18-hACE2 mice reduced viral loads in the lungs and brains of the vaccinated animals and protected the mice against challenge with SARS-CoV-2. In monkeys, the results of safety pharmacology tests, general clinical observations, and a core battery of studies of three vital systems, namely, the central nervous, cardiovascular, and respiratory systems, did not reveal any safety concerns. The toxicology study of the vaccine in rats showed no vaccine-related pathological changes, and all the animals remained healthy under the conditions of this study. Furthermore, the vaccine did not cause any abnormal toxicity in rats and was clinically tolerated even at the highest tested concentration. In addition, general health status, body temperature, local toxicity at the administration site, hematology, and blood chemistry parameters were also monitored. Overall, this work presents the results of the first systematic study of the safety profile of a plant-derived vaccine, Baiya SARS-CoV-2 Vax 1; this approach can be considered a viable strategy for the development of vaccines against COVID-19.  相似文献   
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