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Publication
Journal: Journal of Basic and Clinical Physiology and Pharmacology
April/19/2016
Abstract
BACKGROUND
Human health is affected by space weather component [solar (SA), geomagnetic (GMA), cosmic ray (CRA) - neutrons, space proton flux] activity levels. The aim of this study was to check possible links between timing of human (both genders) monthly deaths distribution and space weather activity.
METHODS
Human deaths distribution in the Republic of Lithuania from 1989 to 2013 (25 years, i.e., 300 consecutive months) was studied, which included 1,050,503 deaths (549,764 male, 500,739 female). Pearson correlation coefficients (r) and their probabilities (p) were obtained for years: months 1-12, sunspot number, smoothed sunspot number, solar flux (2800 MGH, 10.7 cm), adjusted solar flux for SA; A, C indices of GMA; neutron activity at the earth's surface (imp/min) for CRA. The cosmophysical data were obtained from space science institutions in the USA, Russia and Finland. The mentioned physical parameters were compared with the total number of deaths, deaths from ischemic heart disease (n=376,074), stroke (n=132,020), non-cardiovascular causes (n=542,409), accidents (n=98,805), traffic accidents (n=21,261), oncology (n=193,017), diabetes mellitus (n=6631) and suicide (n=33,072).
RESULTS
Space factors were interrelated as follows for the considered period: CRA was inversely related to SA and GMA, CRA/SA (r=-0.86, p>0.0001), CRA/GMA (r=-0.70, p<0.0001); SA and GMA were correlated (r=0.50, p<0.0001). The total deaths distribution was inversely related to SA (r=-0.31, p<0.0001) and correlated with CRA (neutron) activity (r=0.234, p<0.0001). Ischemic heart disease (IHD) deaths (most at home) show a drop yearly (r=-0.2551), more for men. It was correlated with GMA for the total IHD population and men. Stroke deaths were inversely related to SA (r=-0.38, p<0.0001) and correlated with CRA (r=0.41, p<0.0001) and year (r=0.49, p<0.0001), showing a steady rise. The IHD/stroke deaths ratio was negatively correlated with the years of observation (r=-0.754, p=0.0001). Non-cardiovascular deaths were inversely related to SA (r=-039, p<0.0001) and correlated with CRA (r=0.263, p<0.0001). Oncology deaths that now are dominating in many places were inversely related to SA (r=-0.475, p<0.0001) and correlated with CRA (r=0.426, p<0.0001). Suicide showed a drop with years (r=-0.29, p<0.0001), possibly related to excessive immigration of young population (18-34 years) in the last decade and correlated with two of three GMA indices. Traffic accidents were correlated with SA and GMA (r=0.392-0.461, p<0.0001) and inversely related to CRA (r=-0.436).
CONCLUSIONS
Most groups of deaths are related to space weather component activity. Extreme levels of activities of both groups (SA, GMA, and opposite CRA - neutron) are related to some health risks. In the considered period, there were relatively few GMA storms and low GMA was dominating, accompanied by higher CRA (neutron) activity. The ways of action of the components of space weather on the human body need additional studies. There is a special need for the prevention of rising cerebral vascular accidents and oncology malignancies as the causes of death.
Publication
Journal: PLoS ONE
August/2/2016
Abstract
Ectoine is a compatible solute and chemical chaperone widely used by members of the Bacteria and a few Archaea to fend-off the detrimental effects of high external osmolarity on cellular physiology and growth. Ectoine synthase (EctC) catalyzes the last step in ectoine production and mediates the ring closure of the substrate N-gamma-acetyl-L-2,4-diaminobutyric acid through a water elimination reaction. However, the crystal structure of ectoine synthase is not known and a clear understanding of how its fold contributes to enzyme activity is thus lacking. Using the ectoine synthase from the cold-adapted marine bacterium Sphingopyxis alaskensis (Sa), we report here both a detailed biochemical characterization of the EctC enzyme and the high-resolution crystal structure of its apo-form. Structural analysis classified the (Sa)EctC protein as a member of the cupin superfamily. EctC forms a dimer with a head-to-tail arrangement, both in solution and in the crystal structure. The interface of the dimer assembly is shaped through backbone-contacts and weak hydrophobic interactions mediated by two beta-sheets within each monomer. We show for the first time that ectoine synthase harbors a catalytically important metal co-factor; metal depletion and reconstitution experiments suggest that EctC is probably an iron-dependent enzyme. We found that EctC not only effectively converts its natural substrate N-gamma-acetyl-L-2,4-diaminobutyric acid into ectoine through a cyclocondensation reaction, but that it can also use the isomer N-alpha-acetyl-L-2,4-diaminobutyric acid as its substrate, albeit with substantially reduced catalytic efficiency. Structure-guided site-directed mutagenesis experiments targeting amino acid residues that are evolutionarily highly conserved among the extended EctC protein family, including those forming the presumptive iron-binding site, were conducted to functionally analyze the properties of the resulting EctC variants. An assessment of enzyme activity and iron content of these mutants give important clues for understanding the architecture of the active site positioned within the core of the EctC cupin barrel.
Publication
Journal: Epidemiology and Infection
July/27/1988
Abstract
During the outbreak of influenza due to A (H3N3) viruses in Finland in 1985/6 virus pairs were isolated from the same clinical specimens in embryonated hens' eggs (CE) and in canine kidney cell cultures (MDCK). Some of these isolates, the E and M pairs, were distinguished by their reactions in haemagglutination inhibition (HI) tests carried out using polyclonal antisera, and by receptor-binding properties, as evidenced by differences in their elution activity from erythrocytes. Passage of the E- and M-virus isolates in the foreign host affected their serological characteristics, but the E virus did not convert to an M-like virus and the M virus did not convert to an E-like virus. Returning the viruses to grow in the host used for their isolation changed the serological reactions so that they were once more close to the reactions of the original isolates. This contrasts with the changes in receptor-binding properties. Rapid elution from hen erythrocytes, which has been described as a property of viruses binding to the SA alpha 2,3Gal sequence in preference to SA alpha 2,6Gal, characterized the virus passages grown solely in MDCK cell cultures. Cultivation of the M virus in CE, at any stage of its passage history, made the virus irreversibly incapable of elution. The M virus was more sensitive than the E virus to HI antibodies against heterologous viruses of the H3N2 subtype, and, when used as an antigen in HI serology, it more frequently (90% vs. 69%; P less than 0.01) detected diagnostic antibody responses in patients infected with viruses of this subtype in 1985/6. Use of antigens with a different passage history in HI serology provided evidence that this superiority, which may be due to the ability of the virus to pick out anamnestic antibody responses, is unrelated to the receptor-binding peculiarity of the M virus under consideration. The results support the concept that the host cell can select a diversity of virus variant subpopulations from a single clinical specimen during isolation and subsequent cultivation procedures. Moreover, the MDCK-grown influenza viruses may correspond better than the egg-grown isolates to the natural epidemic viruses.
Publication
Journal: International Journal for Parasitology
January/22/2012
Abstract
The phylogeography and host specificity of three monogenean species infecting different sites on the southern fiddler ray, Trygonorrhina fasciata (Rhinobatidae) in South Australia (SA) were studied: Branchotenthes octohamatus (Hexabothriidae: gills), Calicotyle australis (Monocotylidae: cloaca) and Pseudoleptobothrium aptychotremae (Microbothriidae: skin). Five rhinobatid species (Aptychotrema vincentiana, T. fasciata, Trygonorrhina sp. A, Aptychotrema rostrata and Rhinobatos typus) with distributions spanning west, south and east Australian coastal waters, were surveyed for monogeneans resembling the three species documented from T. fasciata in SA. The identities of hosts and parasites collected were investigated using the mitochondrial genes ND4 and Cytochrome b (cytb), respectively, in addition to the nuclear marker, Elongation factor 1-alpha (EF1a) for Pseudoleptobothrium. Genetic analyses confirmed that B. octohamatus is geographically widespread and displays little genetic structure, suggesting high levels of gene flow. It was collected from four rhinobatid species throughout its distribution and is not, therefore, host specific. For C. australis, genetic analyses revealed two discrete populations with a genetic divergence of ∼4%, one population occurring west of Bass Strait on two sympatric host species and the other population on the east coast, also occurring on sympatric host species. Similarly, for Pseudoleptobothrium, specimens collected west of Bass Strait were genetically distinct (∼3.5%) from those collected to the east. However, on the east coast, a third Pseudoleptobothrium population was revealed, separated by a genetic distance of >11%, indicating a morphologically cryptic species. Host preferences were indicated for each Pseudoleptobothrium lineage. These genetic discoveries are discussed in relation to life history characteristics of each monogenean species, highlighting the value of phylogeographic analyses to understand the parasite-host relationship.
Publication
Journal: BMC Bioinformatics
September/13/2009
Abstract
BACKGROUND
Advances in high-throughput technologies available to modern biology have created an increasing flood of experimentally determined facts. Ordering, managing and describing these raw results is the first step which allows facts to become knowledge. Currently there are limited ways to automatically annotate such data, especially utilizing information deposited in published literature.
RESULTS
To aid researchers in describing results from high-throughput experiments we developed HT-SAS, a web service for automatic annotation of proteins using general English words. For each protein a poll of Medline abstracts connected to homologous proteins is gathered using the UniProt-Medline link. Overrepresented words are detected using binomial statistics approximation. We tested our automatic approach with a protein test set from SGD to determine the accuracy and usefulness of our approach. We also applied the automatic annotation service to improve annotations of proteins from Plasmodium bergei expressed exclusively during the blood stage.
CONCLUSIONS
Using HT-SAS we created new, or enriched already established annotations for over 20% of proteins from Plasmodium bergei expressed in the blood stage, deposited in PlasmoDB. Our tests show this approach to information extraction provides highly specific keywords, often also when the number of abstracts is limited. Our service should be useful for manual curators, as a complement to manually curated information sources and for researchers working with protein datasets, especially from poorly characterized organisms.
Publication
Journal: Journal of Elder Abuse and Neglect
March/13/2013
Abstract
This study explored the feasibility of seniors aged 65 and over with MMSE ≥24 completing the EASI-sa, a self-administrable version of the Elder Abuse Suspicion Index (EASI). A convenience sample of 210 was stratified by age, sex, and language (English and French). All completed the EASI-sa within an estimated 5 minutes, 82.9% within 2 minutes. Completion time decreased with higher education, but was not affected by age, sex, language, or measured physical or mental health. No questions went unanswered; no words were poorly understood or discomforting. The EASI-sa completion was associated with a significantly increased understanding about elder abuse (p < 0.0001).
Publication
Journal: Applied Optics
August/19/2018
Abstract
In this research, we present results of simulated annealing (SA), a heuristic optimization algorithm, for focusing light through a turbid medium. Performance of the algorithm on phase and amplitude modulations has been evaluated. A number of tips to tune the optimization parameters are provided. The effect of measurement noise on the performance of the SA algorithm is explored. Additionally, SA performance is compared with continuous sequential and briefly with other optimization algorithms.
Publication
Journal: Spine Journal
October/22/2015
Abstract
BACKGROUND
The Surgical Apgar Score (SAS), a simple metric based on intraoperative heart rate, blood pressure, and blood loss, was developed in general and vascular surgery to predict 30-day major postoperative complications and mortality. No validation of SAS has been performed in spine surgery.
OBJECTIVE
To perform a prospective assessment of SAS in spine surgery.
METHODS
Prospective study.
METHODS
Two hundred sixty-eight consecutive patients undergoing major and intermediate spinal surgeries in an 18-month period.
METHODS
Occurrence of major complications or death within 30 days of surgery.
METHODS
Intraoperative parameters were registered, and SAS was calculated immediately after surgery. Outcome data were collected during a 30-day follow-up. The relationship between SAS and the outcomes was analyzed calculating relative risks (RRs) and likelihood ratios (LRs) for different scoring groups. A univariate logistic regression analysis was also performed. The discriminatory accuracy of SAS was evaluated calculating a C-statistic.
RESULTS
Eighteen patients had ≥1 complications (6.72%). Patients with SAS 9-10 exhibited a 1.64% complication rate (RR=1; LR=0.23), which monotonically augmented as the score decreased: (SAS 7-8=2.75%; RR=1.68; LR=0.39), (SAS 5-6=13.33%; RR=8.13; LR=2.14), (SAS≤4=17.39%; RR=10.61; LR=2.92). The regression analysis odds ratio was 0.66 (95% confidence interval, 0.54-0.82), p<.01. The C-statistic was 0.77 (95% confidence interval, 0.66-0.88).
CONCLUSIONS
Surgical Apgar Score allows risk stratification and has a good discriminatory power in patients undergoing spine surgery.
Publication
Journal: Annales d'Endocrinologie
October/29/2007
Abstract
Endocrine pancreatic tumors (EPTs) are uncommon tumors, representing 1-2% of all pancreatic neoplasms. They are categorized on the basis of their clinical features into functioning and non-functioning tumors. EPTs may be part of the multiple endocrine neoplasia type 1 (MEN 1), an autosomal dominant syndrome due to inactivating germline mutation of the menin gene. Somatic mutations of menin are present in about 20% of sporadic neoplasms, particularly gastrinomas and insulinomas. 30-75% of patients with MEN1 have EPTs. The most prevalent are the gastrinomas (20-60%), then the insulinomas (5-10%), the glucagonamas and VIPomas (6-10%), whereas the nonfunctioning EPTs are present in 20-40% of patients. The most important biochemical screening marker for EPTs is chromogranin A, as it increases in 50-80% of patients. The most important negative prognostic factors are the presence of metastases, the gross invasion of adjacent organs, the angioinvasion, the perineural invasion and an immunopositivity for Ki-67>> 2%. Among the different imaging techniques, echoendoscopy, computed tomography (CT) and magnetic resonance imaging (MRI) are indicated for the detection of the primary tumor, but (III)In-octreotide scintigraphy has the highest sensitivity for detecting metastases. The choice of treatment is still debated and is different when the tumor occurs as a part of the MEN syndrome. The surgical treatment is the first choice for insulinomas and is more controversial for gastrinomas. The medical treatment includes somatostatin analogues (SA), chemotherapy and interferon-alpha (IFN-alpha). SA seem to improve the symptoms and have an antiproliferative effect, the most striking effect being seen in patients with VIPomas. Chemotherapy, which is generally proposed as a combination of streptozotocin (STZ) and 5-fluorouracil (5-FU) or doxorubicin, is indicated when the tumors tend to grow. Interferon-alpha (IFN-alpha) stimulates the immune system, blocks the tumor cells in the G1/S-phase of the cell cycle, inhibits protein and hormone synthesis and inhibits angionenesis. Treatment with IFN has been shown to produce symptomatic response in 40-60% of patients, a biochemical response in 30-60% and tumor shrinkage in 10-15%.
Publication
Journal: Zhongguo yao li xue bao = Acta pharmacologica Sinica
June/24/1999
Abstract
OBJECTIVE
To study influence of congestive heart failure (CHF) and acute myocardial infarction (AMI) on alpha 1-acid glycoprotein (AGP) and sialic acid (SA) concentration, and binding of AGP to disopyramide (Dis).
METHODS
Sera from 85 healthy subjects, 6 patients with CHF, and 6 patients with AMI were determined by immunochemistry for AGP, by HPLC method for sialic acid (SA), and by ultrafiltration and HPLC for the free fraction of Dis.
RESULTS
Serum AGP concentrations (g.L-1) were 0.74 +/- 0.16 (healthy), 1.18 +/- 0.40 (d 1, CHF) and 0.90 +/- 0.24 (d 14, CHF), 1.53 +/- 0.26 (d 5, AMI) and 1.08 (d 14, AMI). The free Dis were 1.76 +/- 0.62 (d 1) and 2.14 +/- 0.48 (d 14), in CHF patients, 1.66 +/- 0.52 (d 5) and 1.77 (d 14) in AMI patients. The changes of serum SA and AGP concentrations showed the same tendency.
CONCLUSIONS
The free Dis in serum was affected by the change of AGP binding in CHF and AMI patients.
Publication
Journal: Annals of Hematology
August/4/1993
Abstract
The case of a patient (Col) with multiple myeloma presenting as chronic cold agglutinin (CA) syndrome is reported. The CA (Col) was a monoclonal IgA/k paraprotein which recognizes an antigen fully expressed in adult and newborn erythrocytes, sialidase sensitive and partially resistant to proteases. Hemagglutination-inhibition studies showed that immunodominant N-acetylneuraminic acid bound alpha 2-->3 to O-glycans of glycophorins represents the CA(Col) epitope. These serological and biochemical findings fit with the anti-Sa specificity, of which only two previous examples are known. The clinical manifestations of CA (Col) were characterized by marked acrocyanosis, generalized livedo reticularis, and incapacitating dyspnea, but only mild hemolysis. Plasma-exchange therapy was effective in quickly removing the CA and relieving the associated clinical manifestations, but such benefit was only temporary. This is the first reported example of anti-Sa CA of IgA isotype and the first case of IgA CA syndrome treated by plasma exchange.
Publication
Journal: Archives of Oral Biology
March/2/1998
Abstract
The cystatin family of proteins exists in both excreted and intracellular forms, and appears to be involved in protective and regulatory roles, inhibiting a variety of bacterial, viral and intracellular proteases. The amino acid sequences of several human forms of cystatin are known, but currently only the structure of chicken cystatin (approx. 40% homologous to the human forms) has been experimentally determined. The objective of this study was to use the X-ray coordinates of chicken cystatin to construct computer models of the structures of three human salivary forms (SN, S and SA). These structures were energy-minimized and subjected to dynamic simulations. The resultant structures were compared to determine conformational differences. Global root mean square deviations between equivalent atoms ranged from 1.4 A to 3.9 A. The closest structural similarity to chicken cystatin involved cystatin SN, which also showed the highest (68%) functional sequence homology. Local secondary structure was examined in more detail. In comparisons of alpha-carbon position the third beta-strand (77% functional sequence conservation) and its preceding loop (60% conserved) showed the highest structural conservation in S, while beta-strand 4 showed the highest structural conservation in SN and SA. Throughout their structures, SN and SA were more structurally similar to chicken cystatin than to salivary cystatin S. There are two regions of conserved, negatively charged residues in the salivary cystatins, which appear to be spaced so that they are capable of interaction with hydroxypatite. It is concluded that not only does structural modelling by analogy provide detailed models of salivary cystatins that can be tested by future experimentation, but also that examination of the models has revealed potential sites of interaction with hydroxyapatite.
Publication
Journal: Pulmonary Pharmacology and Therapeutics
February/11/2002
Abstract
The inhalation of alpha(1)-protease inhibitor (alpha(1)-PI) was assessed in a pilot study to restore the protease-antiprotease balance in the lungs of cystic fibrosis (CF) patients. In addition, the effect of this treatment on the surface active properties of lung surfactant and the metabolic conversion of aggregate forms was studied. Eight young adults with CF inhaled 100 mg of alpha(1)-PI twice daily over 8 weeks and bronchoalveolar lavages (BAL) were obtained before and 12 h after the last inhalation. Large aggregate (LA) forms of surfactant were isolated from the in vivo material by ultracentrifugation and their conversion into small aggregates (SA) was assessed by an in vitro surface area cycling assay. Although alpha(1)-PI partially restored the protease-anti-protease imbalance and reduced BAL protein content, no effects were noted on the impaired minimal surface tension and on the in vivo and in vitro conversion of LA to SA. Antiserum against the specific carboxyl esterase ES-2, previously identified in mice and rats as the putative surfactant convertase, did not detect a protein of the appropriate size in CF BAL. Whereas short-term inhalation of alpha(1)-PI was beneficial for the proteolytic aspects of CF lung injury, this appeared not to be the case for surfactant conversion and surface activity.
Publication
Journal: Current Pharmaceutical Design
August/15/2013
Abstract
Stable angina (SA) pectoris is a common and disabling disorder in patients with coronary artery disease (CAD), with increasing epidemiology and is associated with myocardial infarction and increased mortality. However, within the population of SA patients, an individual's prognosis can vary considerably. Except from conventional risk factors a variety of biomarkers have been evaluated for their prognostic significance in the settings of SA. Novel biomarkers associated with inflammatory status, such as C reactive protein and tumor necrosis factor alpha, with myocardial performance, such as B-type natriuretic peptide, with extracellular matrix remodeling, with vascular calcification such as osteoprotogerin and osteopontin, with myocardial ischemia, such as ischemia modified albumin have been associated with the progression of CAD and with the prognosis of SA patients. Despite the multiplicity of novel biomarkers there is lack of a clinical useful, highly specific for CAD biomarker with the ability to guide treatment decisions. In the context of this evidence in this review article we summarize the so far acquired knowledge of the most promising biomarkers and we discuss the major clinical correlations of novel risk factors with SA physical history, their predictive value for future cardiovascular events and their use in the treatment monitoring of this population.
Publication
Journal: Biomaterials
December/7/2004
Abstract
Acetylation of starch considerably decreases its swelling and enzymatic degradation. Thus, starch-acetate (SA) based delivery systems may be suitable for controlled drug delivery. The aim of the present study was to evaluate drug release from the SA microparticles (SA mps) and SA films. The average degree of acetyl substitution (DS) per glucose residue in the starch was either 1.9 (SA DS 1.9) or 2.6 (SA DS 2.6). Timolol (mw 332), calcein (mw 623) and bovine serum albumin (BSA, mw 68,000) were used as model drugs. A continuous timolol release from the both SA mps was observed in phosphate buffer solution (PBS) pH 7.4 (50-days incubation). The release of timolol was faster from the SA DS 1.9 mps than from the SA DS 2.6 mps. Calcein release from both SA mps was continuous in PBS pH 7.4 (5-days incubation). But, calcein release profile from the SA DS 2.6 film in PBS pH 7.4 showed discontinuities. However, the release of calcein from both SA films was continuous in human serum in vitro during the 7-day incubation, i.e. enzymes enhanced calcein release. Thus, alpha-amylase was incorporated into the SA films in order to enhance drug release from the films. However, the effects of incorporation of alpha-amylase on the model macromolecule (BSA) release from the SA films were modest. In conclusion, this study demonstrates the achievement of slow release of different molecular weight model drugs from the SA mps and films as compared to fast release from the native starch preparations. DS of SA, physicochemical properties of a drug and the presence of enzymes can all affect drug release profiles from SA based preparations.
Publication
Journal: Analytical and Bioanalytical Chemistry
December/16/2013
Abstract
Glycosylation is an important posttranslational modification of proteins and plays a crucial role in both cellular functions and secretory pathways. Sialic acids (SAs), a family of nine-carbon-containing acidic monosaccharides, often terminate the glycan structures of cell surface molecules and secreted glycoproteins and perform an important role in many biological processes. Hence, a more profound profiling of the sialylated glycoproteomics may improve our knowledge of this modification and its effects on protein functions. Here, we systematically investigated different strategies to enrich the SA proteins in human plasma using a newly developed technology that utilizes titanium dioxide for sialylated N-glycoproteomics profiling by mass spectrometry. Our results showed that using a combination of a filter-aided sample preparation method, TiO2 chromatography, multiple enzyme digestion, and two-dimensional reversed-phase peptide fractionation led to a more profound profiling of the SA proteome. In total, 982 glycosylation sites in 413 proteins were identified, among which 37.8% were newly identified, to establish the largest database of sialic acid containing proteins from human plasma.
Publication
Journal: International Journal of Food Microbiology
August/19/2009
Abstract
The objective of this study was to investigate the effect of uptake of different commonly consumed long chain fatty acids on superoxide (O(2)(-)), nitric oxide (NO) production, and ability to kill Salmonella enterica serotype typhimurium (S. typhimurium) by chicken macrophages (HD11 cells). All the fatty acids were taken up by HD11 cells with stearic acid uptake higher than polyunsaturated fatty acids. Uptake of green fluorescent protein-labeled bacteria and the viability of HD11 cells (measured by flow cytometry) was not affected by any of the fatty acids tested. Bacterial clearance (measured by the plating of sorted viable infected cells) was significantly higher with n-3 fatty acids alpha-linolenic acid (ALA) and docosahexanoic acid (DHA). However, stearic acid (SA) and the n-6 fatty acid, arachidonic acid (ARA) did not influence S. typhimurium killing by HD11 cells. The improved S. typhimurium clearance by ALA and DHA was not associated with increased NO or O(2)(-) production by HD11 cells. These results suggest a role for n-3 polyunsaturated fatty acids in Salmonella clearance by chicken macrophages however in vivo studies are essential to confirm their efficacy in controlling Salmonella infection in chickens and contamination in shell eggs.
Publication
Journal: Zhong xi yi jie he xue bao = Journal of Chinese integrative medicine
January/22/2014
Abstract
OBJECTIVE
To investigate the effects of salvianolic acid B (SA-B) on cardiovascular endothelial cell function and platelet activation during myocardial ischemia-reperfusion in rabbits.
METHODS
A total of 24 New Zealand white rabbits were randomly divided into sham-operated group, ischemia-reperfusion group (untreated group) and SA-B group. The hearts of rabbits in untreated group and SA-B group underwent half an hour of left anterior descending coronary artery (LADCA) occlusion via ligation technology, which was followed by 4 hours of reperfusion to prepared ischemia-reperfusion injury model in vivo. For sham-operated group, the animals were not subjected to occlusion of LADCA. In SA-B treatment group the rabbits were intravenously administered SA-B immediately after LADCA occlusion, and the other two groups were given normal saline in the same way instead of SA-B. The jugular vein bloods of animals were collected before LADCA ligation, half an hour after ligation and after 1-, 4-hour reperfusion, respectively. The content of plasma nitric oxide (NO) was determined by nitrate reductase process. Radioimmunoassay was applied to detect the endothelin (ET) content in plasma and the count of alpha-granule membrane protein-140 (GMP-140) on platelet surface to identify the activation of the platelet.
RESULTS
No significant difference was observed before and after sham LADCA occlusion in sham-operated group in the contents of NO and ET in plasma (P>0.05), neither was the count of GMP-140 on platelet surface (P>0.05). The content of NO in plasma detected 0.5 h after LADCA occlusion was significantly decreased in untreated group compared with the sham-operated group at the corresponding time, and they were also much lower than that before LADCA occlusion in the sham-operated group (P<0.05). The plasma content of NO in untreated group showed a progressive decrease in response to the myocardial reperfusion. However, the content of ET in plasma and the count of GMP-140 on platelet surface were remarkably increased after myocardial ischemia as compared with those before LADCA ligation and those detected in sham-operated group (P<0.05). The content of ET and the count of GMP-140 in the untreated group were further increased corresponding to the aggressive reperfusion. The content of NO was significantly increased while the content of ET and the count of GMP-140 were both significantly decreased in SA-B group as compared with untreated group after 1- and 4-hour myocardial reperfusion, respectively (P<0.01).
CONCLUSIONS
The results show that endothelial dysfunction and platelet activation occur during ischemia-reperfusion in rabbit hearts in vivo and SA-B protects cardiovascular endothelium cells against ischemia-reperfusion injury and inhibits the activation of platelet during myocardial ischemia and reperfusion.
Publication
Journal: The American journal of physiology
March/22/1998
Abstract
Acute lung inflammation is complicated by altered pulmonary surfactant phospholipid and protein composition. The proinflammatory cytokine tumor necrosis factor-alpha (TNF-alpha) and the phorbol ester 12-O-tetradecanoyl phorbol-13-acetate (TPA) inhibit expression of surfactant-associated proteins A and B (SP-A and SP-B), both important for normal surfactant function. The transcription factor nuclear factor-kappa B (NF-kappa B) frequently mediates regulation of gene expression by TPA and TNF-alpha. In the present study, electrophoretic mobility shift assays (EM-SAs) and pyrrolidine dithiocarbamate (PDTC), an inhibitor of NF-kappa B activation, were utilized to determine the role of NF-kappa B activation in TPA and TNF-alpha inhibition of the surfactant proteins in NCI-H441 cells. Pentoxifylline (PTX), which inhibits TNF-alpha cellular effects without preventing NF-kappa B activation, was also tested. By EMSA, TPA and TNF-alpha increased nuclear NF-kappa B binding activity in temporally distinct patterns. PDTC decreased TPA- and TNF-alpha-induced NF-kappa B binding activity but did not limit their inhibition of SP-A and SP-B mRNAs. PDTC independently decreased both SP-A and SP-B mRNAs. PTX partially reversed TNF-alpha-but not TPA-mediated inhibition of SP-A and SP-B mRNAs without altering NF-kappa B binding. The effects of PDTC and PTX on NF-kappa B and the surfactant proteins suggest that NF-kappa B activation does not mediate TPA or TNF-alpha inhibition of SP-A and SP-B mRNA accumulation.
Publication
Journal: Journal of steroid biochemistry
February/16/1987
Abstract
Steroid alcohol sulfotransferase (SAS) has been isolated from the cytosol of a human breast carcinoma cell line, MCF-7. This enzyme from Sephadex G-200 chromatography displayed a mol. wt of 118 KDa. The conditions for optimal enzymic activity of SAS were determined to be 20 min incubations at 45 degrees C in 0.2 M Tris buffer (pH 7.5) containing 0.06 M Mg2+. Chromatofocusing chromatography also yielded a single peak of SAS with a pI of 5.8. Results from the incubations of a series of androstane analogues revealed that SAS required a 3 beta-hydroxyl on a steroid with the trans bridge between the A and B rings. Neither the 3 beta-allylic hydroxyl group nor the A-ring phenolic 3-hydroxyl accepted the sulfate group from 3'-phosphoadenosine-5'-phosphosulfate. D-ring beta-hydroxyl groups were tolerated by the enzyme, however, alpha-hydroxyl groups on the D-ring appeared to interfere with the reaction. Sulfurylation of steroids by SAS was related inversely to the sum of the displacements of the 3-hydroxyl plus that of the 17-hydroxyl groups relative to the plane of symmetry of the dehydroepiandrosterone nucleus. This enzyme was also capable of sulfurylating short chain aliphatic alcohols, although at greatly reduced rates. 3 beta-Chloro-5-androstene-17-one and 2-nitroestradiol. 17 beta proved to be the best inhibitors of SAS.
Publication
Journal: Chemico-Biological Interactions
March/3/2004
Abstract
Sanguinarine (SA), a member of the benzo[c]phenanthridine isoquinoline alkaloids, has been shown to possess antimicrobial, anti-inflammatory, and antioxidant properties. We examined the effects of SA on oxidative burst in DMSO-differentiated HL-60 cells, an excellent model for studying oxidative burst. SA inhibited both N-formyl-Met-Leu-Phe (fMLP) and phorbol 12-myristate 13-acetate (PMA)-induced oxidative burst with half-maximal concentration for inhibition (IC(50)) of 1.5 and 1.8 microM, respectively. Despite suggestions of SA antioxidant activity this inhibition cannot be ascribed to radical scavenging property of SA because the IC(50) for superoxide dismutase-like activity in a non-cellular system was 60 microM. TROLOX, a water-soluble vitamin E analog, had IC(50) of 3 microM in the same system. Moreover, cyclic voltammetry measurements show that SA is not an easily oxidizable species, with a peak anodic potential at 700 mV, as compared to TROLOX with peak anodic potential at 200 mV. On the other hand, TROLOX, when used in cell suspension, was much poorer inhibitor of oxidative burst than SA. When testing direct effect of SA on NADPH oxidase in the post-granular fraction of disrupted cells, the IC(50) was found to be 8.3 microM. It is higher than that observed in whole cells, however, the shift may be ascribed to SDS effect on SA activity. We conclude the SA inhibition of oxidative burst is not caused by SA redox activity but most likely is a result of SA affecting the activity of NADPH oxidase directly and in part by preventing the formation of NADPH oxidase protein complex.
Publication
Journal: Glycobiology
December/29/2010
Abstract
Trypanosoma cruzi, the agent of American trypanosomiasis is unable to synthesize sialic acid (SA). Instead of using the corresponding nucleotide sugar as donor of the monosaccharide, the transfer occurs from alpha-2,3-linked SA in the host sialoglycoconjugates to terminal beta-galactopyranosyl units of the parasite mucins. For that purpose, T. cruzi expresses a glycosylphosphatidylinositol-anchored trans-sialidase (TcTS) that is shed into the milieu, being detected in the blood during the acute phase of the infection. The essential role of TcTS in infection and the absence of a similar activity in mammals make this enzyme an attractive target for the development of alternative chemotherapies. However, there is no effective inhibitor toward this enzyme. In vitro, 3'-sialyllactose (SL) as donor and radioactive lactose as acceptor substrate are widely used to measure TcTS activity. The radioactive sialylated product is then isolated by anion exchange chromatography and measured. Here we describe a new nonradioactive assay using SL or fetuin as donor and benzyl beta-d-Fuc-(1-->6)-alpha-d-GlcNAc (1) as acceptor. Disaccharide 1 was easily synthesized by regioselective glycosylation of benzyl alpha-d-GlcNAc with tetra-O-benzoyl-d-fucose followed by debenzoylation. Compound 1 lacks the hydroxyl group at C-6 of the acceptor galactose and therefore is not a substrate for galactose oxidase. Our method relies on the specific quantification of terminal galactose produced by trans-sialylation from the donor to the 6-deoxy-galactose (D-Fuc) unit of 1 by a spectrophotometric galactose oxidase assay. This method may also discriminate sialidase and trans-sialylation activities by running the assay in the absence of acceptor 1.
Publication
Journal: Research communications in chemical pathology and pharmacology
October/24/1978
Abstract
Two somatostatin analogues (SA) and 17-alpha-dihydroequilin (E) inhibited the stereospecific binding of 3H-naloxone in vitro to rat brain opiate receptors in the absence of sodium. The addition of sodium indicated the SA to be greater or similar in potency to somatostatin as opiate agonists and E to be an opiate antagonist. The results indicate that SA and certain steroids may affect endorphin containing neurons.
Publication
Journal: Pain
June/22/1997
Abstract
This study examined the effects of intravenous administration of sodium amytal (SA), a medium action barbiturate, on cutaneous limb temperatures and sympathetic skin responses (SSR) to electrical stimulation. Eight normal volunteers and 13 patients with musculoskeletal pain, somatoform pain disorders or nerve/root injury (with findings strictly limited to the distribution of the distribution of the involved nerve) were compared to 15 patients with Complex Regional Pain syndromes (one of whom had documented nerve injury). The Complex Regional Pain Syndromes (CRPS) patients were characterized by the presence of severe diffuse limb pain and extraterritorial sensory, sudomotor and vasomotor abnormalities (i.e., not confined to the site of injury or the distribution of the injured nerve). The CRPS patients were different from the normal controls and the non-CRPS patients in their tendency to warm significantly many of their limbs (not just the symptomatic ones). SSR were reduced or lost in a few limbs only in all three groups, irrespective of the increase or decrease of limb temperature and the side of symptoms. We argue that the enhanced thermogenic effect of SA in CRPS patients is due to generalized central changes of thermoregulatory control specifically in this group.
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