Discards and bycatch: A review of wasted fishing.

Bycatch and discards are a significant issue for global fisheries, with discards considered unnecessary mortality and wasted fishing. Discards have declined due to more selective gear and changes in regulations, but data on discard rates and species remains challenging to collect. Addressing discards is crucial to minimize food waste and increase seafood production.

Investigating conspecific CsRV1 transmission in Callinectes sapidus.

A reo-like virus, CsRV1, is found in blue crabs, Callinectes sapidus, from every North American location assessed, including Chesapeake Bay and the Atlantic and Gulf coasts, USA and associated with blue crabs in softshell production. CsRV1-associated crab mortality is prevalent in captive crabs, but it is still unknown how CsRV1 is transmitted. The purpose of this study was to examine the role that conspecific predation or scavenging may play in per os transmission in single exposure and repeated exposure experiments.

Microsporidia Ameson earli sp. n. and A. michaelis (Sprague 1965) infecting blue crabs Callinectes sapidus from shedding facilities in Louisiana.

During a survey for pathogens and commensals of blue crabs in commercial soft shell shedding facilities in Louisiana, we discovered an occurrence of microsporidiosis in two of forty examined crabs. Judging from spore shape and size, tissue tropism and external signs of muscle pathology, the causative agent of infections was identified as Ameson michaelis, a muscle-infecting species that has been repeatedly detected in populations of Callinectes sapidus in Louisiana since 1965. However, retrospective ultrastructural examination revealed that in one of Ameson-infected crabs, infection was caused by a parasite with ultrastructural characters not completely compliant with the ones of A.

Counterbalancing angiogenic regulatory factors control the rate of cancer progression and survival in a stage-specific manner.

Whereas the roles of proangiogenic factors in carcinogenesis are well established, those of endogenous angiogenesis inhibitors (EAIs) remain to be fully elaborated. We investigated the roles of three EAIs during de novo tumorigenesis to further test the angiogenic balance hypothesis, which suggests that blood vessel development in the tumor microenvironment can be governed by a net loss of negative regulators of angiogenesis in addition to the well-established principle of up-regulated angiogenesis inducers. In a mouse model of pancreatic neuroendocrine cancer, administration of endostatin, thrombospondin-1, and tumstatin peptides, as well as deletion of their genes, reveal neoplastic stage-specific effects on angiogenesis, tumor progression, and survival, correlating with endothelial expression of their receptors.

Elevated Flk1 (vascular endothelial growth factor receptor 2) signaling mediates enhanced angiogenesis in beta3-integrin-deficient mice.

Tumor growth, tumor angiogenesis, and vascular endothelial growth factor (VEGF)-specific angiogenesis are all enhanced in beta(3)-integrin-null mice. Furthermore, endothelial cells isolated from beta(3)-null mice show elevated levels of Flk1 (VEGF receptor 2) expression, suggesting that beta(3)-integrin can control the amplitude of VEGF responses by controlling Flk1 levels or activity. We now show that Flk1 signaling is required for the enhanced tumor growth and angiogenesis seen in beta(3)-null mice.

Integrin alpha1beta1 and alpha2beta1 are the key regulators of hepatocarcinoma cell invasion across the fibrotic matrix microenvironment.

As with many types of cancer, cell motility is an important factor in the progression and metastasis of hepatocellular carcinomas (HCC). HCC is associated with significant fibrosis in the liver. The fibrotic microenvironment in the liver is characterized by an altered composition of the extracellular matrix (ECM) and an abundance of growth factors that are likely conducive to migration of HCC cells.

Physiological levels of tumstatin, a fragment of collagen IV alpha3 chain, are generated by MMP-9 proteolysis and suppress angiogenesis via alphaV beta3 integrin.

We demonstrate a physiological role for tumstatin, a cleavage fragment of the alpha3 chain of type IV collagen (Col IValpha3), which is present in the circulation. Mice with a genetic deletion of Col IValpha3 show accelerated tumor growth associated with enhanced pathological angiogenesis, while angiogenesis associated with development and tissue repair are unaffected. Supplementing Col IValpha3-deficient mice with recombinant tumstatin to a normal physiological concentration abolishes the increased rate of tumor growth.

Human tumstatin and human endostatin exhibit distinct antiangiogenic activities mediated by alpha v beta 3 and alpha 5 beta 1 integrins.

Tumstatin and endostatin are two inhibitors of angiogenesis derived from precursor human collagen molecules known as alpha 3 chain of type IV collagen and alpha1 chain of type XVIII collagen, respectively. Although both these inhibitors are noncollagenous (NC1) domain fragments of collagens, they only share a 14% amino acid homology. In the present study we evaluated the functional receptors, mechanism of action, and intracellular signaling induced by these two collagen-derived inhibitors.

Enhanced pathological angiogenesis in mice lacking beta3 integrin or beta3 and beta5 integrins.

Inhibition of alphavbeta3 or alphavbeta5 integrin function has been reported to suppress neovascularization and tumor growth, suggesting that these integrins are critical modulators of angiogenesis. Here we report that mice lacking beta3 integrins or both beta3 and beta5 integrins not only support tumorigenesis, but have enhanced tumor growth as well. Moreover, the tumors in these integrin-deficient mice display enhanced angiogenesis, strongly suggesting that neither beta3 nor beta5 integrins are essential for neovascularization.

Tumstatin, an endothelial cell-specific inhibitor of protein synthesis.

Tumstatin is a 28-kilodalton fragment of type IV collagen that displays both anti-angiogenic and proapoptotic activity. Here we show that tumstatin functions as an endothelial cell-specific inhibitor of protein synthesis. Through a requisite interaction with alphaVbeta3 integrin, tumstatin inhibits activation of focal adhesion kinase (FAK), phosphatidylinositol 3-kinase (PI3-kinase), protein kinase B (PKB/Akt), and mammalian target of rapamycin (mTOR), and it prevents the dissociation of eukaryotic initiation factor 4E protein (eIF4E) from 4E-binding protein 1.