Micronemal Transport of Plasmodium Ookinete Chitinases to the Electron-Dense Area of the Apical Complex for Extracellular Secretion

2000 ◽  
Vol 68 (11) ◽  
pp. 6461-6465 ◽  
Author(s):  
Rebecca C. Langer ◽  
Rhian E. Hayward ◽  
Takafumi Tsuboi ◽  
Mayumi Tachibana ◽  
Motomi Torii ◽  
...  
2000 ◽  
Vol 68 (11) ◽  
pp. 6461-6465 ◽  
Author(s):  
Rebecca C. Langer ◽  
Rhian E. Hayward ◽  
Takafumi Tsuboi ◽  
Mayumi Tachibana ◽  
Motomi Torii ◽  
...  

ABSTRACT Plasmodium ookinetes secrete chitinases to penetrate the acellular, chitin-containing peritrophic matrix of the mosquito midgut en route to invasion of the epithelium. Chitinases are potentially targets that can be used to block malaria transmission. We demonstrate here that chitinases of Plasmodium falciparumand P. gallinaceum are concentrated at the apical end of ookinetes. The chitinase PgCHT1 of P. gallinaceum is present within ookinete micronemes and subsequently becomes localized in the electron-dense area of the apical complex. These observations suggest a pathway by which ookinetes secrete proteins extracellularly.


2019 ◽  
Vol 19 (10) ◽  
pp. 826-832 ◽  
Author(s):  
Zhi-Gang Sun ◽  
Ting-Ting Zhao ◽  
Na Lu ◽  
Yong-An Yang ◽  
Hai-Liang Zhu

Glycyrrhizic acid (GA), a triterpene isolated from the roots and rhizomes of licorice, named Glycyrrhiza glabra, is the principal bioactive ingredient of anti-viral, anti-inflammatory and hepatoprotective effects. GA has been used in the clinical treatment of hepatitis, bronchitis, gastric ulcer, AIDS (acquired immunodeficiency syndrome), certain cancers and skin diseases. It has a direct effect on anti-HBV (hepatitis B virus) via affecting the HBsAg (hepatitis B surface antigen) to extracellular secretion, improving liver dysfunction in patients with chronic hepatitis B, and ultimately improving the immune status of HBV. GA can significantly inhibit the proliferation of HIV, showing an immune activation. The clinical application of GA on the prevention and treatments of various diseases may derive from its numerous pharmacological properties. This review provides the summary of the antiviral effects of GA on research progress and mechanism in recent years.


Cancers ◽  
2021 ◽  
Vol 13 (13) ◽  
pp. 3245
Author(s):  
Emma C. Atakpa ◽  
Adam R. Brentnall ◽  
Susan Astley ◽  
Jack Cuzick ◽  
D. Gareth Evans ◽  
...  

We evaluated the association between short-term change in body mass index (BMI) and breast density during a 1 year weight-loss intervention (Manchester, UK). We included 65 premenopausal women (35–45 years, ≥7 kg adult weight gain, family history of breast cancer). BMI and breast density (semi-automated area-based, automated volume-based) were measured at baseline, 1 year, and 2 years after study entry (1 year post intervention). Cross-sectional (between-women) and short-term change (within-women) associations between BMI and breast density were measured using repeated-measures correlation coefficients and multivariable linear mixed models. BMI was positively correlated with dense volume between-women (r = 0.41, 95%CI: 0.17, 0.61), but less so within-women (r = 0.08, 95%CI: −0.16, 0.28). There was little association with dense area (between-women r = −0.12, 95%CI: −0.38, 0.16; within-women r = 0.01, 95%CI: −0.24, 0.25). BMI and breast fat were positively correlated (volume: between r = 0.77, 95%CI: 0.69, 0.84, within r = 0.58, 95%CI: 0.36, 0.75; area: between r = 0.74, 95%CI: 0.63, 0.82, within r = 0.45, 95%CI: 0.23, 0.63). Multivariable models reported similar associations. Exploratory analysis suggested associations between BMI gain from 20 years and density measures (standard deviation change per +5 kg/m2 BMI: dense area: +0.61 (95%CI: 0.12, 1.09); fat volume: −0.31 (95%CI: −0.62, 0.00)). Short-term BMI change is likely to be positively associated with breast fat, but we found little association with dense tissue, although power was limited by small sample size.


2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Zhengchuan Zhang ◽  
Ruogu Xu ◽  
Yang Yang ◽  
Chaoan Liang ◽  
Xiaolin Yu ◽  
...  

Abstract Background Micro/nano-textured hierarchical titanium topography is more bioactive and biomimetic than smooth, micro-textured or nano-textured titanium topographies. Bone marrow mesenchymal stem cells (BMSCs) and exosomes derived from BMSCs play important roles in the osseointegration of titanium implants, but the effects and mechanisms of titanium topography on BMSCs-derived exosome secretion are still unclear. This study determined whether the secretion behavior of exosomes derived from BMSCs is differently affected by different titanium topographies both in vitro and in vivo. Results We found that both micro/nanonet-textured hierarchical titanium topography and micro/nanotube-textured hierarchical titanium topography showed favorable roughness and hydrophilicity. These two micro/nano-textured hierarchical titanium topographies enhanced the spreading areas of BMSCs on the titanium surface with stronger promotion of BMSCs proliferation in vitro. Compared to micro-textured titanium topography, micro/nano-textured hierarchical titanium topography significantly enhanced osseointegration in vivo and promoted BMSCs to synthesize and transport exosomes and then release these exosomes into the extracellular environment both in vitro and in vivo. Moreover, micro/nanonet-textured hierarchical titanium topography promoted exosome secretion by upregulating RAB27B and SMPD3 gene expression and micro/nanotube-textured hierarchical titanium topography promoted exosome secretion due to the strongest enhancement in cell proliferation. Conclusions These findings provide evidence that micro/nano-textured hierarchical titanium topography promotes exosome biogenesis and extracellular secretion for enhanced osseointegration. Our findings also highlight that the optimized titanium topography can increase exosome secretion from BMSCs, which may promote osseointegration of titanium implants.


2021 ◽  
Vol 12 (1) ◽  
pp. 19
Author(s):  
Bartosz Nowak ◽  
Mateusz Kawka ◽  
Kamil Wierzchowski ◽  
Katarzyna Sykłowska-Baranek ◽  
Maciej Pilarek

Unique biosynthetic abilities revealed by plants determine in vitro cultures of hairy roots as a suitable source of pharmaceutically relevant bioactive compounds. The basic aim of the study was to examine the applicability of aerogel composed of methyltrimethoxysilane (MTMS) for immobilization of Rindera graeca hairy roots by identifying quantitative effects of biomass proliferation and naphthoquinones extracellular secretion in the aerogel-supported culture system. R. graeca hairy roots were simultaneously cultured for 28-days, as (i) nonimmobilized biomass (reference system), (ii) biomass immobilized on macroporous polyurethane foam (PUF), (iii) biomass with disintegrated MTMS aerogel, (iv) biomass immobilized on polypropylene (PP) fibers (as control), and (v) biomass immobilized on monolithic PP-reinforced MTMS aerogel. MTMS aerogel exhibited high level of biocompatibility toward R. graeca hairy roots which grew into the structure of monolithic aerogel-based constructs. Monolithic MTMS-based constructs significantly promoted the proliferation of hairy roots, resulting in 55% higher fresh mass than the reference system. The highest level of naphthoquinones productivity, i.e., 653 µg gDW−1, was noted for PUF-supported culture system.


Biomolecules ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 519
Author(s):  
Michał Piegza ◽  
Joanna Pietrzykowska ◽  
Joanna Trojan-Piegza ◽  
Wojciech Łaba

Biosurfactants represent a structurally diverse group of secondary metabolites produced by bacteria, yeasts, and filamentous fungi. Their character is often associated with numerous additional properties. The observation of Trichoderma fungi of various species used as a source of bioinhibitors against pathogenic plants fungi focuses attention to the often quite specific behavior of preparations in contact with, among others, plant leaves, dependent on strain. Thus, an evaluation of the selected strains belonging to the species: T. atroviride, T. citrinoviride,T. reesei and T. harzianum was conducted towards their capability of the extracellular secretion of surfactants, with a simultaneous attempt to pre-determine their chemical nature. Two mineral-organic media were used for this purpose, and the culture fluid was extensively tested using a variety of methods. A decrease in surface tension was observed in culture fluid of each tested strain, especially T. citrinoviride HL and C1. The results strongly depended on medium composition, of which Saunders 1 and MGP 1 were most beneficial. The secreted compounds were further analyzed to pre-determine their chemical nature using IR, GC, and NMR. In the case of most efficient biosurfactant producers, a lipopeptide structure of the surfactants was concluded.


2019 ◽  
Vol 53 (13) ◽  
pp. 7746-7758 ◽  
Author(s):  
Myrna M. T. de Rooij ◽  
Gerard Hoek ◽  
Heike Schmitt ◽  
Ingmar Janse ◽  
Arno Swart ◽  
...  
Keyword(s):  

PLoS ONE ◽  
2011 ◽  
Vol 6 (12) ◽  
pp. e29460 ◽  
Author(s):  
Takafumi Hasegawa ◽  
Masatoshi Konno ◽  
Toru Baba ◽  
Naoto Sugeno ◽  
Akio Kikuchi ◽  
...  

1994 ◽  
Vol 28 (1) ◽  
pp. 1-7 ◽  
Author(s):  
J. Dyson ◽  
J. Grahame ◽  
P.J. Evennett
Keyword(s):  

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