Search results for "Glycoprotein"
showing 10 items of 852 documents
Evidence of the Red-Queen Hypothesis from Accelerated Rates of Evolution of Genes Involved in Biotic Interactions in Pneumocystis.
2018
Pneumocystis species are ascomycete fungi adapted to live inside the lungs of mammals. These ascomycetes show extensive stenoxenism, meaning that each species of Pneumocystis infects a single species of host. Here, we study the effect exerted by natural selection on gene evolution in the genomes of three Pneumocystis species. We show that genes involved in host interaction evolve under positive selection. In the first place, we found strong evidence of episodic diversifying selection in Major surface glycoproteins (Msg). These proteins are located on the surface of Pneumocystis and are used for host attachment and probably for immune system evasion. Consistent with their function as antigen…
A targeted proteomics investigation of the obesity paradox in venous thromboembolism
2021
Abstract The obesity paradox, the controversial finding that obesity promotes disease development but protects against sequelae in patients, has been observed in venous thromboembolism (VTE). The aim of this investigation was to identify a body mass–related proteomic signature in VTE patients and to evaluate whether this signature mediates the obesity paradox in VTE patients. Data from the Genotyping and Molecular Phenotyping in Venous ThromboEmbolism Project, a prospective cohort study of 693 VTE patients, were analyzed. A combined end point of recurrent VTE or all-cause death was used. Relative quantification of 444 proteins was performed using high-throughput targeted proteomics technolo…
SARS-CoV2 vertical transmission with adverse effects on the newborn revealed through integrated immunohistochemical, electron microscopy and molecula…
2020
Background: The occurrence of trans-placental transmission of severe acute respiratory syndrome corona virus 2 (SARS-CoV-2) infection remains highly debated. Placental positivity for SARS-CoV-2 has been reported in selected cases, but infection or virus-associated disease of fetal tissues or newborns remains to be demonstrated. Methods: We screened for SARS-CoV-2 spike (S) protein expression placentas from 101 women who delivered between February 7 and May 15 2020, including 15 tested positive for SARS-CoV-2 RNA, 34 tested negative, and 52 not evaluated as they did not meet testing criteria (32), or delivered before COVID-19 pandemic declaration (20). Immunostain for SARS-CoV-2 nucleocapsid…
Mesopolysaccharides: The extracellular surface layer of visceral organs
2020
The mesothelium is a dynamic and specialized tissue layer that covers the somatic cavities (pleural, peritoneal, and pericardial) as well as the surface of the visceral organs such as the lung, heart, liver, bowel and tunica vaginalis testis. The potential therapeutic manipulation of visceral organs has been complicated by the carbohydrate surface layer—here, called the mesopolysaccharide (MPS)—that coats the outer layer of the mesothelium. The traditional understanding of MPS structure has relied upon fixation techniques known to degrade carbohydrates. The recent development of carbohydrate-preserving fixation for high resolution imaging techniques has provided an opportunity to re-examine…
Substrate Specificity of Aglaia loheri Active Isolate towards P-glycoprotein in Multidrug-Resistant Cancer Cells
2016
Multidrug resistance (MDR) is a major contributory factor in the failure of chemotherapy. Concrete interpretation of P-glycoprotein (P-gp) substrate specificity, whether a substance is a substrate or an inhibitor, represents an important feature of a compound's pharmaceutical profiling in drug design and development. In this work, the P-gp substrate specificity of Maldi 531.2[M+H]+, a phenol ester from Aglaia loheri Blanco leaves was investigated. This study focuses on the effect of Maldi 531.2[M+H]+ on P-gp ATPase activity, which was examined by measuring the amount of inorganic phosphates (Pi) released as a result of ATP hydrolysis. To test the effects of Maldi 531.2[M+H]+ on MDR activit…
Niemann-Pick type C2 protein supplementation in experimental non-alcoholic fatty liver disease
2017
BACKGROUND AND AIMS: Hepatic cholesterol deposition drives inflammation and fibrosis in non-alcoholic steatohepatitis (NASH). The Niemann-Pick type C2 (NPC2) protein plays an important role in regulating intracellular cholesterol trafficking and homeostasis. We hypothesized that intravenous NPC2 supplementation reduces cholesterol accumulation, hepatic inflammation and fibrogenesis in a nutritional NASH rat model.METHODS: Rats were fed a high-fat, high-cholesterol (HFHC) diet for four weeks resulting in moderately severe NASH. Animals were treated with intravenous NPC2 or placebo twice weekly for either the last two weeks or the entire four weeks. End-points were liver/body- and spleen/body…
SERCA and P-glycoprotein inhibition and ATP depletion are necessary for celastrol-induced autophagic cell death and collateral sensitivity in multidr…
2019
Multidrug resistance (MDR) represents an obstacle in anti-cancer therapy. MDR is caused by multiple mechanisms, involving ATP-binding cassette (ABC) transporters such as P-glycoprotein (P-gp), which reduces intracellular drug levels to sub-therapeutic concentrations. Therefore, sensitizing agents retaining effectiveness against apoptosis- or drug-resistant cancers are desired for the treatment of MDR cancers. The sarcoplasmic/endoplasmic reticulum Ca2+ ATPase (SERCA) pump is an emerging target to overcome MDR, because of its continuous expression and because the calcium transport function is crucial to the survival of tumor cells. Previous studies showed that SERCA inhibitors exhibit anti-c…
Essential Oils, Pituranthos chloranthus and Teucrium ramosissimum, Chemosensitize Resistant Human Uterine Sarcoma MES-SA/Dx5 Cells to Doxorubicin by …
2021
The multidrug resistance phenotype is a global phenomenon and causes chemotherapy failure in various cancers, such as in uterine sarcomas that have a high mortality rate. To overcome this phenotype, there is growing research interest in developing new treatment strategies. In this study, we highlight the potential of two essential oils from the Apiaceae family, Pituranthos chloranthus (PC) and Teucrium ramosissimum Desf. (TR), to act as chemopreventive and chemosensitizing agents against two uterine sarcoma cell lines, MES-SA and P-gp-overexpressing MES-SA/Dx5 cells. We found that PC and TR were able to inhibit the cell viability of sensitive MES-SA and resistant MES-SA/Dx5 cells by a sligh…
Mammalian plasma fetuin-B is a selective inhibitor of ovastacin and meprin metalloproteinases
2019
AbstractVertebrate fetuins are multi-domain plasma-proteins of the cystatin-superfamily. Human fetuin-A is also known as AHSG, α2-Heremans-Schmid-glycoprotein. Gene-knockout in mice identified fetuin-A as essential for calcified-matrix-metabolism and bone-mineralization. Fetuin-B deficient mice, on the other hand, are female infertile due to zona pellucida ‘hardening’ caused by the metalloproteinase ovastacin in unfertilized oocytes. In wildtype mice fetuin-B inhibits the activity of ovastacin thus maintaining oocytes fertilizable. Here we asked, if fetuins affect further proteases as might be expected from their evolutionary relation to single-domain-cystatins, known as proteinase-inhibito…
Host Cell Calpains Can Cleave Structural Proteins from the Enterovirus Polyprotein
2019
Enteroviruses are small RNA viruses that cause diseases with various symptoms ranging from mild to severe. Enterovirus proteins are translated as a single polyprotein, which is cleaved by viral proteases to release capsid and nonstructural proteins. Here, we show that also cellular calpains have a potential role in the processing of the enteroviral polyprotein. Using purified calpains 1 and 2 in an in vitro assay, we show that addition of calpains leads to an increase in the release of VP1 and VP3 capsid proteins from P1 of enterovirus B species, detected by western blotting. This was prevented with a calpain inhibitor and was dependent on optimal calcium concentration, especially for calpa…