Uterine curettage or surgical trauma can cause uterine vascular abnormalities, including pseudoaneurysms, acquired arteriovenous malformations (AVMs), arteriovenous fistulas, and rupture of vessels. Recognition of these abnormalities as the cause of hemorrhage is important, since these abnormalities can be treated safely and effectively with transcatheter arterial embolization but may be worsened by uterine curettage, precipitating massive uterine bleeding. Ultrasonography (US) is the most commonly performed initial imaging examination for evaluation of abnormal uterine bleeding. Color and duplex Doppler US allows convincing detection and diagnosis of these vascular abnormalities and helps differentiate vascular abnormalities that require embolization from nonvascular abnormalities. In cases of pseudoaneurysms, color and duplex Doppler US shows a blood-filled cystic structure with swirling arterial flow. In cases of AVMs, color Doppler US shows an intense vascular tangle, whereas duplex Doppler US shows low-resistance, high-velocity arterial flow. Cases of an AVM combined with a pseudoaneurysm demonstrate the findings of both AVMs and pseudoaneurysms. Transcatheter arterial embolization after angiography is the therapy of choice for these vascular abnormalities, with the advantage of retained reproductive capacity. Routine use of color and duplex Doppler US during examination of abnormal uterine bleeding is recommended to identify and characterize the vascular abnormality.
Chronic passive hepatic congestion (congestive hepatopathy) leads to hepatic fibrosis; however the mechanisms involved in this process are not well understood. We developed a murine experimental model of congestive hepatopathy through partial ligation of the inferior vena cava (pIVCL). C57BL/6 and transgenic mice overexpressing tissue factor pathway inhibitor (SM22α -TFPI) were subjected to pIVCL or SHAM. Liver and blood samples were collected and analyzed in immunohistochemical, morphometric, real-time polymerase chain reaction and western blot assays. Hepatic fibrosis and portal pressure were significantly increased after pIVCL concurrent with hepatic stellate cell (HSC) activation. Liver stiffness, as assessed by magnetic resonance elastography, correlated with portal pressure and preceded fibrosis in our model. Hepatic sinusoidal thrombosis as evidenced by fibrin deposition was demonstrated both in mice after pIVCL as well as in humans with congestive hepatopathy. Warfarin treatment and TFPI overexpression both had a protective effect on fibrosis development and HSC activation after pIVCL. In vitro studies show that congestion stimulates HSC fibronectin (FN) fibril assembly through direct effects of thrombi as well as by virtue of mechanical strain. Pretreatment with either Mab13 or Cytochalasin-D, to inhibit β-integrin or actin polymerization, respectively, significantly reduced fibrin and stretch induced FN fibril assembly. Conclusion Chronic hepatic congestion leads to sinusoidal thrombosis and strain, which in turn promote hepatic fibrosis. These studies mechanistically link congestive hepatopathy to hepatic fibrosis.
SummaryLaccase efficiently catalyses polymerization of phenolic compounds. However, knowledge on applications of polymers synthesized in this manner remains scarce. Here, the potential of laccase‐catalysed polymerization of natural phenols to form products useful in hair dyeing was investigated. All 15 tested phenols yielded coloured products after laccase treatment and colour diversity was attained by using mixtures of two phenolic monomers. After exploring colour differentiation pattern of 120 different reactions with statistical regression analysis, three monomer combinations, namely gallic acid and syringic acid, catechin and catechol, and ferulic acid and syringic acid, giving rise to brown, black, and red materials, respectively, were further characterized because such colours are commercially important for grey hair dyeing. Selected polymers could strongly absorb visible light and their hydrodynamic sizes ranged from 100 to 400 nm. Analyses of enzyme kinetic constants, liquid chromatography and electrospray ionization‐mass spectrometry (ESI‐MS) coupled with collision‐induced dissociation MS/MS indicate that both monomers in reactions involving catechin and catechol, and ferulic acid and syringic acid, are coloured by heteropolymer synthesis, but the gallic acid/syringic acid combination is based on homopolymer mixture formation. Comparison of colour parameters from these three reactions with those of corresponding artificial homopolymer mixtures also supported the idea that laccase may catalyse either hetero‐ or homo‐polymer synthesis. We finally used selected materials to dye grey hair. Each material coloured hair appropriately and the dyeing showed excellent resistance to conventional shampooing. Our study indicates that laccase‐catalysed polymerization of natural phenols is applicable to the development of new cosmetic pigments.
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