Dissintegration of bone cement by continual and pulsating water jet

Članak se bavi proučavanjem uporabe kontinuiranog vodenog mlaza i nadzvučnog pulsirajućeg mlaza vode za dezintegraciju koštanog cementa. Koštani cement Pallacos R+G (ručno miješan) dezintegriran je ex-vivo. Mehanička svojstva koštanog cementa određena su pomoću nano-utiskivanja. Faktori u procjeni bili su tlakovi (40, 80, 120) MPa i poprečna brzina kontinuiranog mlaza vode, tlak (8, 10, 12, 14, 16, 20) MPa i tip prigušnice (ravna, kružna) za nadzvučni pulsirajući mlaz vode. Dubina prodiranja h (mm) mjerena je bezkontaktnim optičkim profilometerom MicroProf FRT. Rezultati predstavljaju prvi korak ka izvedivosti uporabe učinkovite tehnike vodenog mlaza tijekom reimplantacije cementiranih endoproteza, za uklanjanje koštanog cementa iz bedrenog kanala bez topline i mehaničkog oštećenja okolnog tkiva.The paper deals with the study of using continuous water jet and ultrasonic pulsating water jet for bone cement disintegration. Bone-cement Pallacos R+G (manually mixed) was disintegrated ex-vivo. Mechanical properties of the bone cement were determined by nano-indentation. Factors employed in evaluation were pressure (40, 80, 120) MPa and traverse speed for continuous water jet, pressure (8, 10, 12, 14, 16, 20) MPa and orifice type (flat, circular) for ultrasonic pulsating water jet. Depth penetration h (mm) was measured by non-contact optical profilometer MicroProf FRT. Results represent the first step towards feasibility of using effective water jet technique during reimplantation of cemented endoprosthesis, for bone cement removal from femoral canal without heat and mechanical damage of surrounding tissue

Homolog of BRCA2-interacting Dss1p and Uap56p link Mlo3p and Rae1p for mRNA export in fission yeast

The breast cancer tumor suppressor BRCA2-interacting protein, DSS1, and its homologs are critical for DNA recombination in eukaryotic cells. We found that Dss1p, along with Mlo3p and Uap56p, Schizosaccharomyces pombe homologs of two messenger RNA (mRNA) export factors of the NXF–NXT pathway, is required for mRNA export in S. pombe. Previously, we showed that the nuclear pore-associated Rae1p is an essential mRNA export factor in S. pombe. Here, we show that Dss1p and Uap56p function by linking mRNA adapter Mlo3p to Rae1p for targeting mRNA–protein complex (mRNP) to the proteins of the nuclear pore complex (NPC). Dss1p preferentially recruits to genes in vivo and interacts with –FG (phenylalanine glycine) nucleoporins in vivo and in vitro. Thus, Dss1p may function at multiple steps of mRNA export, from mRNP biogenesis to their targeting and translocation through the NPC

Crp79p, Like Mex67p, Is an Auxiliary mRNA Export Factor in Schizosaccharomyces pombe

The export of mRNA from the nucleus to the cytoplasm involves interactions of proteins with mRNA and the nuclear pore complex. We isolated Crp79p, a novel mRNA export factor from the same synthetic lethal screen that led to the identification of spMex67p in Schizosaccharomyces pombe. Crp79p is a 710-amino-acid-long protein that contains three RNA recognition motif domains in tandem and a distinct C-terminus. Fused to green fluorescent protein (GFP), Crp79p localizes to the cytoplasm. Like Mex67p, Crp79-GFP binds poly(A)(+) RNA in vivo, shuttles between the nucleus and the cytoplasm, and contains a nuclear export activity at the C-terminus that is Crm1p-independent. All of these properties are essential for Crp79p to promote mRNA export. Crp79p import into the nucleus depends on the Ran system. A domain of spMex67p previously identified as having a nuclear export activity can functionally substitute for the nuclear export activity at the C-terminus of Crp79p. Although both Crp79p and spMex67p function to export mRNA, Crp79p does not substitute for all of spMex67p functions and probably is not a functional homologue of spMex67p. We propose that Crp79p is a nonessential mRNA export carrier in S. pombe