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1.
Fine needle aspiration biopsies of tumors can yield a variety of spindle cells derived from several types of neoplasms. Among these is a rare lesion known as a "spindle-cell carcinoma" or "pseudosarcoma," which may represent a transformation of a preexisting squamous-cell carcinoma that has been subjected to radiotherapy or solar damage. The cytologic, histologic and ultrastructural features of a case of metastatic spindle-cell carcinoma of the rib subjected to fine needle aspiration are presented, and other spindle-cell tumors that should be considered in the differential diagnosis are discussed.  相似文献   
2.
Evidence demonstrates that M1 macrophage polarization promotes inflammatory disease. Here, we discovered that (R)‐salbutamol, a β2 receptor agonist, inhibits and reprograms the cellular metabolism of RAW264.7 macrophages. (R)‐salbutamol significantly inhibited LPS‐induced M1 macrophage polarization and downregulated expressions of typical M1 macrophage cytokines, including monocyte chemotactic protein‐1 (MCP‐1), interleukin‐1β (IL‐1β) and tumour necrosis factor α (TNF‐α). Also, (R)‐salbutamol significantly decreased the production of inducible nitric oxide synthase (iNOS), nitric oxide (NO) and reactive oxygen species (ROS), while increasing the reduced glutathione (GSH)/oxidized glutathione (GSSG) ratio. In contrast, (S)‐salbutamol increased the production of NO and ROS. Bioenergetic profiles showed that (R)‐salbutamol significantly reduced aerobic glycolysis and enhanced mitochondrial respiration. Untargeted metabolomics analysis demonstrated that (R)‐salbutamol modulated metabolic pathways, of which three metabolic pathways, namely, (a) phenylalanine metabolism, (b) the pentose phosphate pathway and (c) glycerophospholipid metabolism were the most noticeably impacted pathways. The effects of (R)‐salbutamol on M1 polarization were inhibited by a specific β2 receptor antagonist, ICI‐118551. These findings demonstrated that (R)‐salbutamol inhibits the M1 phenotype by downregulating aerobic glycolysis and glycerophospholipid metabolism, which may propose (R)‐salbutamol as the major pharmacologically active component of racemic salbutamol for the treatment of inflammatory diseases and highlight the medicinal value of (R)‐salbutamol.  相似文献   
3.
4.

Background

There has been no comprehensive study on biochemical characterization of insecticide resistance mechanisms in field populations of Malaysian Culex quinquefasciatus. To fill this void in the literature, a nationwide investigation was performed to quantify the enzyme activities, thereby attempting to characterize the potential resistance mechanisms in Cx. quinquefasciatus in residential areas in Malaysia.

Methodology/Principal Findings

Culex quinquefasciatus from 14 residential areas across 13 states and one federal territory were subjected to esterases, mixed function oxidases, glutathione-S-transferase and insensitive acetylcholinesterase assays. Enzyme assays revealed that α-esterases and β-esterases were elevated in 13 populations and 12 populations, respectively. Nine populations demonstrated elevated levels of mixed function oxidases and glutathione-S-transferase. Acetylcholinesterase was insensitive to propoxur in all 14 populations. Activity of α-esterases associated with malathion resistance was found in the present study. In addition, an association between the activity of α-esterases and β-esterases was also demonstrated.

Conclusions/Significance

The present study has characterized the potential biochemical mechanisms in contributing towards insecticide resistance in Cx. quinquefasciatus field populations in Malaysia. Identification of mechanisms underlying the insecticide resistance will be beneficial in developing effective mosquito control programs in Malaysia.  相似文献   
5.
Cathepsin D was isolated from crude extract of chicken muscle by the purification procedures of acid- and heat-treatments, ammonium sulfate fractionation, DEAE-Sephadex A-50 column chromatography and Sephadex G-100 gel filtration. The enzyme was purified about 3700 fold and homogeneous in disc-electrophoretic analysis. The molecular weight was found to be about 36,000 and the isoelectric point to be pH 7.3. The best substrate for this enzyme was 6 m urea-denatured casein, and its activity was maximal at pH 3.5 and 40°C. This enzyme was most stable between pH 4 and 5, and its stability was affected by cupric ion. The enzyme activity was markedly inhibited by sodium laurylsulfate and oxidizing agents such as potassium permanganate, N-bromosuccinimide and iodine, and was slightly activated by hydrogen peroxide. The purified cathepsin D was found to be fairly similar to the acid protease from lotus seed, previously reported by the authors.  相似文献   
6.
Background: The use of invasive procedures has mostly been studied in retrospective (multi)- national registries. Limited evidence exists on the association between microalbuminuria and coronary artery disease (CAD). Methods: The incidence of major adverse cardiac events (MACE) and invasive cardiac procedures was registered between 1997 and 2003 in 8139 subjects, without prior documented CAD, in the PREVEND cohort study (the Netherlands), in which the focus is on microalbuminuria and cardiovascular risk. Qualitative coronary angiographic analysis was performed. Results: During 5.5 years of follow-up, a first MACE occurred in 271 (3.3%) and a first coronary angiography (CAG) was performed in 264 (3.2%) subjects. Of these, 216 CAGs were available for qualitative angiographic analysis. Indications for CAG were stable angina in 129, acute coronary syndrome (ACS) in 55 and ST-elevation myocardial infarction (STEMI) in 32 subjects. Obstructive coronary artery disease was present in 61, 53 and 30 subjects, respectively. A revascularisation was performed in 50 (39%), 50 (91%) and 25 (78%) subjects, respectively. Microalbuminuria was associated with a first MACE, after adjustment for established risk factors. Microalbuminuria was present at baseline in 9% of subjects with normal coronary arteries, in 21% of subjects with one- and two-vessel CAD and in 39% of subjects with threevessel or left main CAD at CAG during follow-up (Ptrend=0.005). Conclusion: This large cohort study shows that two-thirds of diagnostic CAGs for stable angina were not followed by a revascularisation, in contrast to CAGs for STEMI or ACS. Furthermore, this study shows that microalbuminuria is associated with CAD. (Neth Heart J 2007;15:133-41.)  相似文献   
7.
Sturkenboom  H. N.  van Hattem  V. A. E.  Nieuwland  W.  Paris  F. M. A.  Magro  M.  Anthonio  R. L.  Algin  A.  Lipsic  E.  Bruwiere  E.  Van den Branden  B. J. L.  Polad  J.  Tonino  P.  Tio  R. A. 《Netherlands heart journal》2022,30(2):96-105
Netherlands Heart Journal - The current study aimed to evaluate changes in treatment delay and outcome for ST-segment elevation myocardial infarction (STEMI) in the Netherlands during the first...  相似文献   
8.
Influenza B virus causes significant disease but remains understudied in tropical regions. We sequenced 72 influenza B viruses collected in Kuala Lumpur, Malaysia, from 1995 to 2008. The predominant circulating lineage (Victoria or Yamagata) changed every 1 to 3 years, and these shifts were associated with increased incidence of influenza B. We also found poor lineage matches with recommended influenza virus vaccine strains. While most influenza B virus lineages in Malaysia were short-lived, one circulated for 3 to 4 years.  相似文献   
9.

Background  

Many plasmid-harbouring strains of Lactococcus lactis have been isolated from milk and other sources. Plasmids of Lactococcus have been shown to harbour antibiotic resistance genes and those that express some important proteins. The generally regarded as safe (GRAS) status of L. lactis also makes it an attractive host for the production of proteins that are beneficial in numerous applications such as the production of biopharmaceutical and nutraceutical. In the present work, strains of L. lactis were isolated from cow's milk, plasmids were isolated and characterised and one of the strains was identified as a potential new lactococcal host for the expression of heterologous proteins.  相似文献   
10.
Histone deacetylases (HDACs) 1 and 2 share a high degree of homology and coexist within the same protein complexes. Despite their close association, each possesses unique functions. We show that the upregulation of HDAC2 in colorectal cancer occurred early at the polyp stage, was more robust and occurred more frequently than HDAC1. Similarly, while the expression of HDACs1 and 2 were increased in cervical dysplasia and invasive carcinoma, HDAC2 expression showed a clear demarcation of high-intensity staining at the transition region of dysplasia compared to HDAC1. Upon HDAC2 knockdown, cells displayed an increased number of cellular extensions reminiscent of cell differentiation. There was also an increase in apoptosis, associated with increased p21Cip1/WAF1 expression that was independent of p53. These results suggest that HDACs, especially HDAC2, are important enzymes involved in the early events of carcinogenesis, making them candidate markers for tumor progression and targets for cancer therapy.  相似文献   
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