34 research outputs found
Human Coronary Artery Remodeling, Beginning and End of the Atherosclerotic Process
BACKGROUND, AIMS OF THE STUDY: The objective of the study was to relate the progress of coronary artery remodeling to the earliest stages of the atherosclerotic process. For this purpose, a mathematical model for description of dimensional change of the coronary artery wall and its constituent components was developed and applied. MATERIALS AND METHODS: The study used coronary artery samples randomly taken from each of 83 consecutive, unselected postmortems. All samples were routinely fixed and processed to paraffin for the preparation of right-angled, 5-micron sections, routinely stained and mounted for subsequent analysis. Computer assisted image analysis, using 32 systematic random, radial sampling lines, was used for interactive measurements of distance from centre of lumen to points defining intima, media and adventitia thickness along the radial intercept, which were subsequently tabled for analysis of variance, calculations of (group –vessel) means, and related to stage of pathology. RESULTS: Pre-atherosclerotic changes, before any localised changes in especially intima dimensions, are found, consisting of a process of gradual vascular widening, associated with temporally at least partly dissociated increases in width, which as a fraction of total vessel radius show a phased process. In these, the intima first increases, subsequently remains stable, and finally reduces in width proportionally to the increasing diameter. The media shows a similar initial increase, on average stabilising in the third phase after reaching a plateau value in the second. The adventitia, already increasing in phase 1, continues to increase in phase 2, accelerating in phase 3. The complex process, as found, occurs systematically in all vessels, is distributed circumferentially, and precedes the development of localised lesions of the intima. CONCLUSIONS: The findings suggest the existence of a diffuse complex of changes, consisting of a gradual vascular widening followed by narrowing, with associated mural changes reflecting the atherosclerotic process
Intrathoracic fire during preparation of the left internal thoracic artery for coronary artery bypass grafting
A surgical fire is a serious complication not previously described in the literature with regard to the thoracic cavity. We report a case in which an intrathoracic fire developed following an air leak combined with high pressure oxygen ventilation in a patient with severe chronic obstructive pulmonary disease. The patient presented to our institution with diffuse coronary artery disease and angina pectoris. He was treated with coronary artery bypass graft surgery, including left internal thoracic artery harvesting. Additionally to this rare presentation of an intrathoracic fire, a brief review of surgical fires is included to this paper
Sec61 Inhibitor Apratoxin S4 Potently Inhibits SARS-CoV-2 and Exhibits Broad-Spectrum Antiviral Activity
There is a pressing need for host-directed therapeutics that elicit broad-spectrum antiviral activities to potentially address current and future viral pandemics. Apratoxin S4 (Apra S4) is a potent Sec61 inhibitor that prevents cotranslational translocation of secretory proteins into the endoplasmic reticulum (ER), leading to anticancer and antiangiogenic activity both in vitro and in vivo. Since Sec61 has been shown to be an essential host factor for viral proteostasis, we tested Apra S4 in cellular models of viral infection, including SARS-CoV-2, influenza A virus, and flaviviruses (Zika, West Nile, and Dengue virus). Apra S4 inhibited viral replication in a concentration-dependent manner and had high potency particularly against SARS-CoV-2 and influenza A virus, with subnanomolar activity in human cells. Characterization studies focused on SARS-CoV-2 revealed that Apra S4 impacted a post-entry stage of the viral life-cycle. Transmission electron microscopy revealed that Apra S4 blocked formation of stacked double-membrane vesicles, the sites of viral replication. Apra S4 reduced dsRNA formation and prevented viral protein production and trafficking of secretory proteins, especially the spike protein. Given the potent and broad-spectrum activity of Apra S4, further preclinical evaluation of Apra S4 and other Sec61 inhibitors as antivirals is warranted
In Vitro and In Vivo Germ Line Potential of Stem Cells Derived from Newborn Mouse Skin
We previously reported that fetal porcine skin-derived stem cells were capable of differentiation into oocyte-like cells (OLCs). Here we report that newborn mice skin-derived stem cells are also capable of differentiating into early OLCs. Using stem cells from mice that are transgenic for Oct4 germline distal enhancer-GFP, germ cells resulting from their differentiation are expected to be GFP+. After differentiation, some GFP+ OLCs reached 40–45 µM and expressed oocyte markers. Flow cytometric analysis revealed that ∼0.3% of the freshly isolated skin cells were GFP+. The GFP-positive cells increased to ∼7% after differentiation, suggesting that the GFP+ cells could be of in vivo origin, but are more likely induced upon being cultured in vitro. To study the in vivo germ cell potential of skin-derived cells, they were aggregated with newborn ovarian cells, and transplanted under the kidney capsule of ovariectomized mice. GFP+ oocytes were identified within a subpopulation of follicles in the resulting growth. Our finding that early oocytes can be differentiated from mice skin-derived cells in defined medium may offer a new in vitro model to study germ cell formation and oogenesis
Możliwość zastosowania tomografii komputerowej z płaskim detektorem w ocenie umiejscowienia zewnętrznego drenażu komorowego
Background and purpose
New angiographic devices with flat panel detectors allow cross-sectional imaging within the angiographic suite. In patients receiving external ventricular drainage (EVD) to manage hydrocephalus following subarachnoid haemorrhage (SAH), these may help evaluating the position of an EVD without moving the patient to a conventional computed tomography (CT) scanner. It could facilitate patients’ management in a life-threatening status. This study therefore compares conventional CT with post-inter-ventional flat panel detector angiographic CT (FDCT) referring to the determinability of an accurate EVD position.
Material and methods
Twenty patients with SAH received FDCT and conventional CT for primary assessment after EVD insertion. Three single-blinded raters compared both modalities and evaluated the image sufficiency for determining the EVD position, EVD tip, intracranial course and whether a contorted drainage tube could be detected.
Results
FDCT was sufficient to detect a correct EVD position in 82.5% of the cases vs. 100% in conventional CT. Regarding the EVD tip, FDCT delivered at least ‘good’ results in 82.5% vs. 95% in conventional CT data. Determining the EVD intracranial course, FDCT provided at least ‘good’ data in 92.5% vs. 100% in conventional CT. For detecting tube contortion, FDCT provided at least ‘good’ results in 70% vs. 98% in conventional CT.
Conclusions
FDCT is a promising method to determine the correct position of an EVD in patients with SAH. Following a neuroradiological intervention, it facilitates the patients’ management and renders additional transfers to conventional CT unnecessary in the majority of cases.Wstęp i cel pracy
Nowoczesne systemy angiograficzne sprzężone z płaskimi detektorami umożliwiają obrazowanie warstwowe już w sali zabiegowej. U chorych leczonych za pomocą zewnętrznego drenażu komorowego z powodu wodogłowia w następstwie krwawienia podpajęczynówkowe-go obrazowanie pozwala na doraźną ocenę położenia drenu bez konieczności wykonywania tradycyjnej tomografii komputerowej (TK). Metoda ta ułatwia postępowanie z chorym w stanie zagrożenia życia. Porównano zgodność obrazów otrzymanych za pomocą tradycyjnej TK z angiografią TK (angio-TK) sprzężoną z płaskim detektorem w ocenie prawidłowego położenia drenu.
Materiał i metody
U 20 chorych z krwotokiem podpajęczy-nówkowym bezpośrednio po założeniu zewnętrznego drenażu komorowego wykonano tradycyjną TK oraz badanie angio-TK z użyciem płaskiego detektora. Trzech badaczy niezależnie oceniło otrzymane wyniki dotyczące położenia drenu, jego końcówki i przebiegu wewnątrzczaszkowego.
Wyniki
Angio-TK sprzężona z płaskim detektorem pozwoliła na ustalenie prawidłowego położenia drenu w 82,5% przypadków w porównaniu ze 100-procentową dokładnością tradycyjnej TK. Pozycję końcówki drenu zlokalizowano w 82,5% badań za pomocą angio-TK z płaskim detektorem i w 95% badań za pomocą tradycyjnej TK. Wewnątrzczaszkowy przebieg drenu angiograficznie uznano za wiarygodny w 92,5% badań angio-TK przy 100-procentowej zgodności w tradycyjnej TK. Natomiast zagięcie drenu znaleziono odpowiednio w 70% i 98% badań.
Wnioski
Angio-TK sprzężona z płaskim detektorem jest przydatna w lokalizacji zewnętrznego drenażu komorowego u chorych z krwotokiem podpajęczynówkowym. Przeprowadzona w trakcie interwencji upraszcza postępowanie i sprawia, że wykonanie u chorego tradycyjnej TK jest najczęściej zbędne. Jednocześnie wykazano, że angiografia sprzężona z płaskim detektorem nie może zastąpić tradycyjnej TK w ocenie przebiegu krwawienia podpajęczynówkowego