699 research outputs found
Protein domain repetition is enriched in Streptococcal cell-surface proteins
AbstractTandem repetition of domain in protein sequence occurs in all three domains of life. It creates protein diversity and adds functional complexity in organisms. In this work, we analyzed 52 streptococcal genomes and found 3748 proteins contained domain repeats. Proteins not harboring domain repeats are significantly enriched in cytoplasm, whereas proteins with domain repeats are significantly enriched in cytoplasmic membrane, cell wall and extracellular locations. Domain repetition occurs most frequently in S. pneumoniae and least in S. thermophilus and S. pyogenes. DUF1542 is the highest repeated domain in a single protein, followed by Rib, CW_binding_1, G5 and HemolysinCabind. 3D structures of 24 repeat-containing proteins were predicted to investigate the structural and functional effect of domain repetition. Several repeat-containing streptococcal cell surface proteins are known to be virulence-associated. Surface-associated tandem domain-containing proteins without experimental functional characterization may be potentially involved in the pathogenesis of streptococci and deserve further investigation
Cellular apoptosis susceptibility (CSE1L/CAS) protein in cancer metastasis and chemotherapeutic drug-induced apoptosis
The cellular apoptosis susceptibility (CSE1L/CAS) protein is highly expressed in cancer, and its expression is positively correlated with high cancer stage, high cancer grade, and worse outcomes of patients. CSE1L (or CAS) regulates chemotherapeutic drug-induced cancer cell apoptosis and may play important roles in mediating the cytotoxicities of chemotherapeutic drugs against cancer cells in cancer chemotherapy. CSE1L was originally regarded as a proliferation-associated protein and was thought to regulate the proliferation of cancer cells in cancer progression. However, the results of experimental studies showed that enhanced CSE1L expression is unable to increase proliferation of cancer cells and CSE1L regulates invasion and metastasis but not proliferation of cancer cells. Recent studies revealed that CSE1L is a secretory protein, and there is a higher prevalence of secretory CSE1L in the sera of patients with metastatic cancer. Therefore, CSE1L may be a useful serological marker for screening, diagnosis and prognosis, assessment of therapeutic responses, and monitoring for recurrence of cancer. In this paper, we review the expression of CSE1L in cancer and discuss why CSE1L regulates the invasion and metastasis rather than the proliferation of cancer
Major interventions are associated with survival of out of hospital cardiac arrest patients - a population based survey
Background. The overall survival rate of
out-of-hospital cardiac arrest (OHCA)
in Taiwan or even in the whole of Asia
is relatively low. Major interventions,
such as target temperature management
(TTM), coronary artery angiography, and
extracorporeal membrane oxygenation
(ECMO), have been associated with better
patient outcome. However, studies in Taiwan
revealing evidence of the benefits of
these interventions are limited.
Methods. A population-based study used
an 8-year database to analyze overall survival
and risk factors ˝among OHCA patients.
All adult non-trauma OHCA patients
were identified through diagnostic
and procedure codes. Hospital survival
and return of spontaneous circulation
(ROSC) were primary and secondary outcomes.
Logistic regression and Cox regression
analyses were conducted.
Results. There was a relationship between
major interventions (including TTM,
coronary artery angiography, and ECMO)
and better hospital survival. Age, income,
major interventions, and acute myocardial
infarction history were associated with
hospital survival. The adjusted hazard
ratios (HRs) were 0.406 (95% CI, 0.295
to 0.558), 1.109 (95% CI, 1.027 to 1.197),
1.075 (95% CI, 1.002 to 1.154), 1.097 (95%
CI, 1.02 to 1.181) and 0.799(95% CI, 0.677
to 0.942) for patients with major interventions,
age≥50, medium low and low income,
middle income, and acute myocardial
infarction history, respectively.
Conclusion. This population-based study
in Taiwan revealed that older age (≥50),
medium low and low income were associated
with a lower rate of survival. Major
interventions, including TTM, coronary
angiography, and ECMO, were related to
better survival
A panel of tumor markers, calreticulin, annexin A2, and annexin A3 in upper tract urothelial carcinoma identified by proteomic and immunological analysis
BACKGROUND: Upper tract urothelial carcinoma (UTUC) is a tumor with sizable metastases and local recurrence. It has a worse prognosis than bladder cancer. This study was designed to investigate the urinary potential tumor markers of UTUC. METHODS: Between January 2008 and January 2009, urine was sampled from 13 patients with UTUC and 20 healthy adults. The current study identified biomarkers for UTUC using non-fixed volume stepwise weak anion exchange chromatography for fractionation of urine protein prior to two-dimensional gel electrophoresis. RESULTS: Fifty five differential proteins have been determined by comparing with the 2-DE maps of the urine of UTUC patients and those of healthy people. Western blotting analysis and immunohistochemistry of tumor tissues and normal tissues from patients with UTUC were carried out to further verify five possible UTUC biomarkers, including zinc-alpha-2-glycoprotein, calreticulin, annexin A2, annexin A3 and haptoglobin. The data of western blot and immunohistochemical analysis are consistent with the 2-DE data. Combined the experimental data in the urine and in tumor tissues collected from patients with UTUC, the crucial over-expressed proteins are calreticulin, annexin A2, and annexin A3. CONCLUSIONS: Calreticulin, annexin A2, and annexin A3 are very likely a panel of biomarkers with potential value for UTUC diagnosis
Ferulic Acid Enhances Peripheral Nerve Regeneration across Long Gaps
This study investigated the effect of ferulic acid (FA) on peripheral nerve injury. In the in vitro test, the effect of FA on viability of Schwann cells was studied. In the in vivo test, right sciatic nerves of the rats were transected, and a 15 mm nerve defect was created. A nerve conduit made of silicone rubber tube filled with FA (5 and 25 μg/mL), or saline (control), was implanted into the nerve defect. Results show that the number of proliferating Schwann cells increased significantly in the FA-treated group at 25 μg/mL compared to that in the control group. After 8 weeks, the FA-treated group at 25 μg/mL had a higher rate of successful regeneration across the wide gap, a significantly calcitonin gene-related peptide (CGRP) staining of the lamina I-II regions in the dorsal horn ipsilateral to the injury, a significantly diminished number of macrophages recruited, and a significantly shortening of the latency and an acceleration of the nerve conductive velocity (NCV) of the evoked muscle action potentials (MAPs) compared with the controls. In summary, the FA may be useful in the development of future strategies for the treatment of peripheral nerve injury
Identification of low-abundance proteins via fractionation of the urine proteome with weak anion exchange chromatography
<p>Abstract</p> <p>Background</p> <p>Low-abundance proteins are difficultly observed on the two-dimensional gel electrophoresis (2-DE) maps of urine proteome, because they are usually obscured by high-abundance proteins such as albumin and immunoglobulin. In this study, a novel fractionation method was developed for enriching low-abundance proteins by removing high-abundance proteins and progressive elution with salts of various concentrations.</p> <p>Results</p> <p>Stepwise weak anion exchange (WAX) chromatography, which applied DEAE-Sephacel resin with non-fixed volume elution, was used to fractionate urine proteome prior to performing 2-DE. Urine proteome was separated into four fractions by progressively eluting the column with 0 M, 50 mM, 100 mM, and 1 M NaCl solutions. Most of the heavy and light immunoglobulin chains appeared in the eluent. After the high-abundance proteins were removed, various low-abundance proteins were enriched and could be easily identified. The potential of this method for obtaining diversified fractionations was demonstrated by eluting the column separately with Na<sub>2</sub>SO<sub>4 </sub>and MgCl<sub>2 </sub>solutions. The 2-DE maps of the fractions eluted with these different salt solutions of identical ionic strength revealed markedly different stain patterns.</p> <p>Conclusion</p> <p>The present study demonstrated that this fractionation method could be applied for purposes of enriching low-abundance proteins and obtaining diversified fractionations of urine, and potentially other proteomes.</p
Design and performance of an ultrahigh vacuum spectroscopic-imaging scanning tunneling microscope with a hybrid vibration isolation system
A spectroscopic imaging-scanning tunneling microscope (SI-STM) allows the
atomic scale visualization of surface electronic and magnetic structure of
novel quantum materials with high energy resolution. To achieve the optimal
performance, low vibration facility is required. Here, we describe the design
and the performance of an ultrahigh vacuum STM system supported by a hybrid
vibration isolation system that consists of a pneumatic passive and a
piezoelectric active vibration isolation stages. The STM system is equipped
with a 1K pot cryogenic insert and a 9 Tesla superconducting magnet, capable of
continuous SI-STM measurements for 7 days. A field ion microscopy system is
installed for in situ STM tip treatment. We present the detailed vibrational
noise analysis of the hybrid vibration isolation system and demonstrate the
performance of our STM system by taking high resolution spectroscopic maps and
topographic images on several quantum materials. Our results establish a new
strategy to achieve an effective vibration isolation system for high-resolution
STM and other scanning probe microscopy to investigate the nanoscale quantum
phenomena
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