321 research outputs found
Breast reconstruction with transverse rectus abdominis musculocutaneous (TRAM) flap in young women with breast cancer
Since its introduction in 1982, the transverse rectus nbdominis musculocutaneous (TRAM) flop has become the standard for autogenous breast reconstruction. However, it has serious potential complications. In this article, the 10 TRAM flaps performed at Princess Margaret Hospital from December 1993 to September 1994 for young women with breast carcinoma were evaluated to assess the safety and complications of this technique. Majority of the patients were satisfied with the cosmetic
outcome.published_or_final_versio
Subcellular profiling reveals distinct and developmentally regulated repertoire of growth cone mRNAs
Cue-directed axon guidance depends partly on local translation in growth cones. Many mRNA transcripts are known to reside in developing axons, yet little is known about their subcellular distribution or, specifically, which transcripts are in growth cones. Here laser capture microdissection (LCM) was used to isolate the growth cones of retinal ganglion cell (RGC) axons of two vertebrate species, mouse and Xenopus, coupled with unbiased genomewide microarray profiling. An unexpectedly large pool of mRNAs defined predominant pathways in protein synthesis, oxidative phosphorylation, cancer, neurological disease, and signaling. Comparative profiling of "young" (pathfinding) versus "old" (target-arriving) Xenopus growth cones revealed that the number and complexity of transcripts increases dramatically with age. Many presynaptic protein mRNAs are present exclusively in old growth cones, suggesting that functionally related sets of mRNAs are targeted to growth cones in a developmentally regulated way. Remarkably, a subset of mRNAs was significantly enriched in the growth cone compared with the axon compartment, indicating that mechanisms exist to localize mRNAs selectively to the growth cone. Furthermore, some receptor transcripts (e.g., EphB4), present exclusively in old growth cones, were equally abundant in young and old cell bodies, indicating that RNA trafficking from the soma is developmentally regulated. Our findings show that them RNA repertoire in growth cones is regulated dynamically with age and suggest that mRNA localization is tailored to match the functional demands of the growing axon tip as it transforms into the presynaptic terminal. Copyright © 2010 the authors
Isolation and characterisation of human gingival margin-derived STRO-1/MACS+ and MACS− cell populations
Recently, gingival margin-derived stem/progenitor cells isolated via
STRO-1/magnetic activated cell sorting (MACS) showed remarkable periodontal
regenerative potential in vivo. As a second-stage investigation, the present
study's aim was to perform in vitro characterisation and comparison of the
stem/progenitor cell characteristics of sorted STRO-1-positive (MACS+) and
STRO-1-negative (MACS−) cell populations from the human free gingival margin.
Cells were isolated from the free gingiva using a minimally invasive technique
and were magnetically sorted using anti-STRO-1 antibodies. Subsequently, the
MACS+ and MACS− cell fractions were characterized by flow cytometry for
expression of CD14, CD34, CD45, CD73, CD90, CD105, CD146/MUC18 and STRO-1.
Colony-forming unit (CFU) and multilineage differentiation potential were
assayed for both cell fractions. Mineralisation marker expression was examined
using real-time polymerase chain reaction (PCR). MACS+ and MACS− cell
fractions showed plastic adherence. MACS+ cells, in contrast to MACS− cells,
showed all of the predefined mesenchymal stem/progenitor cell characteristics
and a significantly higher number of CFUs (P<0.01). More than 95% of MACS+
cells expressed CD105, CD90 and CD73; lacked the haematopoietic markers CD45,
CD34 and CD14, and expressed STRO-1 and CD146/MUC18. MACS− cells showed a
different surface marker expression profile, with almost no expression of CD14
or STRO-1, and more than 95% of these cells expressed CD73, CD90 and
CD146/MUC18, as well as the haematopoietic markers CD34 and CD45 and CD105.
MACS+ cells could be differentiated along osteoblastic, adipocytic and
chondroblastic lineages. In contrast, MACS− cells demonstrated slight
osteogenic potential. Unstimulated MACS+ cells showed significantly higher
expression of collagen I (P<0.05) and collagen III (P<0.01), whereas MACS−
cells demonstrated higher expression of osteonectin (P<0.05; Mann–Whitney).
The present study is the first to compare gingival MACS+ and MACS− cell
populations demonstrating that MACS+ cells, in contrast to MACS− cells,
harbour stem/progenitor cell characteristics. This study also validates the
effectiveness of the STRO-1/MACS+ technique for the isolation of gingival
stem/progenitor cells. Human free gingival margin-derived STRO-1/MACS+ cells
are a unique renewable source of multipotent stem/progenitor cells
Multi-messenger observations of a binary neutron star merger
On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of ~1.7 s with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg2 at a luminosity distance of 40+8-8 Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to 2.26 Mo. An extensive observing campaign was launched across the electromagnetic spectrum leading to the discovery of a bright optical transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC 4993 (at ~40 Mpc) less than 11 hours after the merger by the One- Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The optical transient was independently detected by multiple teams within an hour. Subsequent observations targeted the object and its environment. Early ultraviolet observations revealed a blue transient that faded within 48 hours. Optical and infrared observations showed a redward evolution over ~10 days. Following early non-detections, X-ray and radio emission were discovered at the transient’s position ~9 and ~16 days, respectively, after the merger. Both the X-ray and radio emission likely arise from a physical process that is distinct from the one that generates the UV/optical/near-infrared emission. No ultra-high-energy gamma-rays and no neutrino candidates consistent with the source were found in follow-up searches. These observations support the hypothesis that GW170817 was produced by the merger of two neutron stars in NGC4993 followed by a short gamma-ray burst (GRB 170817A) and a kilonova/macronova powered by the radioactive decay of r-process nuclei synthesized in the ejecta
Noroviruses subvert the core stress granule component G3BP1 to promote viral VPg-dependent translation.
Knowledge of the host factors required for norovirus replication has been hindered by the challenges associated with culturing human noroviruses. We have combined proteomic analysis of the viral translation and replication complexes with a CRISPR screen, to identify host factors required for norovirus infection. The core stress granule component G3BP1 was identified as a host factor essential for efficient human and murine norovirus infection, demonstrating a conserved function across the Norovirus genus. Furthermore, we show that G3BP1 functions in the novel paradigm of viral VPg-dependent translation initiation, contributing to the assembly of translation complexes on the VPg-linked viral positive sense RNA genome by facilitating ribosome recruitment. Our data uncovers a novel function for G3BP1 in the life cycle of positive sense RNA viruses and identifies the first host factor with pan-norovirus pro-viral activity
Breast-feeding and risk of epithelial ovarian cancer.
Among women who have had the opportunity to breast-feed, ever breast-feeding and increasing durations of episodes of breast-feeding for each breast-fed child are associated with a decrease in the risk of ovarian cancer independent of numbers of births, which may be strongest for the endometrioid subtype
Improvements in 25 Years of Implantable Cardioverter Defibrillator Therapy
In 1980, Dr. Michel Mirowski and his team inserted the first implantable cardioverter defibrillator (ICD) in a patient. Initially, ICD therapy was not widely accepted, and many physicians actually considered this therapy unethical. Large secondary and primary prevention trials, demonstrating a beneficial effect of ICD therapy in selected patients not only on arrhythmic death but also on all-cause mortality, stimulated a rapid growth in the number of implants and increased patient’s and physician’s acceptance. Improvements in size and weight, arrhythmia discrimination capabilities, battery technology, shock waveform and output, monitoring capabilities and defibrillator electrode technology eventually resulted in the current large number of yearly implants. Today, almost 40 years after the conception of the ICD and 25 years after the first human implant, ICD therapy is the treatment of choice for patients at risk for life-threatening arrhythmias either as secondary or primary prevention. Furthermore, with the more recent addition of resynchronisation therapy to standard ICD therapy, it became possible to treat selected patients with advanced symptoms of heart failure and to lower the risk of sudden death
Ventricular tachycardia in ischemic cardiomyopathy; a combined endo-epicardial ablation as the first procedure versus a stepwise approach (EPILOGUE) – study protocol for a randomized controlled trial
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