Low Molecular Weight Glycoprotein Research Articles

Expression of β2 microglobulin on malignant multiple myeloma plasma cells

Background. β2‑microglobulin is a low molecular weight glycoprotein that is part of the major histocompatibility complex. The concentration of β2‑microglobulin in the blood serum of patients increases with various oncohematological pathologies, including multiple myeloma. One of the methods for detecting membrane β2‑microglobulin is flow cytometry. This article discusses the expression of β2‑microglobulin and key markers on the membrane of malignant cells in patients with multiple myeloma at the onset of the disease.Aim. To study the expression of β2‑microglobulin and markers CD45, CD56 and CD19 on the membrane of tumor plasma cells in the primary diagnosis of multiple myeloma.Materials and methods. The study of β2‑microglobulin and CD45, CD56 and CD19 was carried out in 37 patients with multiple myeloma by 8‑color flow cytometry using a panel of monoclonal antibodies for the diagnosis of plasma cell tumors (EuroFlow, 2012).Results. The expression of β2‑microglobulin in combination with markers CD45, CD56 and CD19 on tumor plasma cells was assessed, illustrations of the expression of these markers are presented. Out of 37 patients with multiple myeloma, hyperexpression of β2‑microglobulin was noted in 23 (62.2 %), in other cases there were normal or reduced levels of this protein in other cases.Conclusion. Tumor plasma cells overexpress β2‑microglobulin in a significant percentage of cases (62.2 %). This allows further assessment of the clinical significance of such aberrant expression and its relationship with serum levels of β2‑microglobulin.

Optimization of Affinity Chromatography Based on Sepharose 4B- chitin for Rapid Purification of Urtica dioica Agglutinin.

Today, numerous antimicrobial and anticancer properties have been reported for plant lectins due to their ability to bind to carbohydrates. The Urtica dioica agglutinin (UDA lectin) is a monomeric, small, and low molecular weight glycoprotein. It has attracted the attention of many researchers for identification, treatment, and other clinical purposes. The aim of this study is the optimization of the chitin affinity chromatography based on Sepharose 4B (CNBr-activated Sepharose 4B) for the rapid purification of UDA lectin from Urtica dioica rhizome. The chitin ligands were dissolved in 40% Trichloroacetic acid and attached to Sepharose 4B according to the Amersham-Biosciences instructions. The attachment of the ligand to the Sepharose 4B beads was investigated by Fourier transform infrared (FTIR) spectroscopy. An acidic crude extract of nettle rhizome passes from chromatographic columns in two sizes with dimensions: 24 x 0.51 cm and 8.44 x 0.86 cm. Quantity and quality of purified lectin were calculated by the Bradford microplate method: SDS-PAGE gel electrophoresis and human erythrocyte cell (RBC) hemagglutination, respectively. The analysis of FTIR spectrograms showed that major changes were observed in the fingerprint regions. Besides, due to the dissolution of Sepharose 4B and chitin in the aqueous phase, this difference was not significant in the Imine and Nitrile regions. On the other hand, the comparative results of purification chromatograms showed that increasing the column length causes a smaller half-width and increases the length of the purified peak. Also, it leads to high-quality purified UDA lectin, with a molecular weight of almost 12.5 kDa in gel electrophoresis. Hemagglutination activity on trypsinized red blood cells was displayed, and agglutination of purified UDA lectin started at least at 300 μg.mL-1 concentration. According to our findings, we suggested that dissolving chitin in the polar solvent of Trichloroacetic acid, using Sepharose 4B as the beads of a matrix, and increasing the column length might lead to a decrease in the half-width of the peak. These can increase the purity and concentration of purified UDA lectin, and speed up the purification process. These findings could be used by researchers to accelerate the purification of UDA lectin in other studies, dealing with drug delivery systems, ELISA techniques, and cell growth.

Comparison between Serum Beta -Trace Protein and Soluble α-Klotho as Early Predictors of Diabetic Nephropathy in Patients with Type 2 Diabetes Mellitus

Background: Diabetes mellitus (DM) is a systemic disease with serious micro- and macro-vascular complications. Beta-trace protein (BTP), a novel low-molecular weight glycoprotein and α-Klotho (α-KL) that are promising biomarkers of diabetic nephropathy (DN). Further, the upregulation of α-KL (internal or external) seems to protect the kidneys from renal insults. The aim of this study was to compare between serum BTP and soluble α- KL as early predictors and prognostic biomarkers of diabetic nephropathy in patients with type-2 diabetes. 
 Patients and methods: This was a prospective study, which was carried out at the department of internal medicine, DFM, Al-Azhar University between January 2020 to January 2022. It included 60 patients with type-2 diabetes mellitus, who were divided into three equal groups, and a comparison group (control group) of 20 apparently healthy individuals.
 Results: There was highly statistically significant difference between the four groups regarding Albumin/creatinine ratio (p<0.05), BTP (p<0.001) and soluble α-klotho (p<0.001). Soluble α klotho was negatively correlated with BTP, both of these markers was significantly correlated with Albumin/creatinine ratio.
 Conclusion: Both BTP and soluble α-klotho can be used as early predictors and biomarkers for diabetic nephropathy in type 2 diabetes mellitus.

Preparation of multi-functional magnetic nanoparticles for harvesting low-molecular-weight glycoproteins

低分子量糖蛋白被认为是发现疾病生物标志物的宝库。特异性的萃取吸附剂对这一类化合物的萃取和富集是必不可少的。硼亲和材料在近年来取得了很大的发展,但专门用于选择性富集低分子量糖蛋白的硼亲和材料目前鲜有报道。该文提出了具有多种功能的磁性纳米颗粒(MNPs),用于低分子量糖蛋白的选择性捕获。该多功能磁性纳米颗粒是用硼酸功能化聚合物网络包裹的磁性纳米复合物。该多功能磁性纳米材料是利用磁性的纳米颗粒内核通过在其表面修饰苯硼酸功能团的聚丙烯酸高分子网络链制备得到。该材料不仅具有常规磁性材料在磁分离方面的基本优势,还能提供三重预先设计的先进功能:1)尺寸排阻效应,去除高分子量蛋白质的干扰;2)对低分子量糖蛋白的选择性萃取;3)保护捕获到的低分子量糖蛋白不被降解和污染。该材料的选择性萃取功能来自于硼酸配基与糖蛋白的顺式二醇部分的亲和性,而尺寸限制效应和保护功能则依赖于磁性纳米颗粒表面修饰的聚合物网络,允许低分子量化合物选择性通过。通过实验验证了这些预设的功能,且通过改变聚合物链长可以调节限径效应的阈值。这种多功能磁性纳米复合物可以进一步发展成有前景的纳米探针,不仅可以选择性捕获低分子量糖蛋白,还可以选择性捕获核苷和聚糖等其他具有重要生物学意义的顺式二醇分子。因此,该文报道的材料制备策略为从复杂样品中选择性萃取靶标化合物的多功能吸附剂的设计和合成提供了新思路。

Uninterrupted oral anticoagulant therapy in patients undergoing unplanned percutaneous coronary intervention

Abstract Background To investigate the optimal periprocedural antithrombotic strategy in patients on oral anticoagulants (OAC) who undergoing unplanned percutaneous coronary intervention (PCI). Methods Using data from the SWEDEHEART registry, we identified all patients on OAC who underwent an unplanned PCI, from 2005 to 2017. We compared uninterrupted OAC (U-OAC) vs interrupted OAC (I-OAC) therapy, defined as any discontinuation of OAC at least 24 hours prior to PCI. Outcomes were major adverse cardiac and cerebrovascular events (MACCE), including death, MI or stroke and net adverse cardiac and cerebrovascular events (NACCE), including MACCE or major bleeds, up to 120 days after the index procedure. Results We included 6485 patients, 3163 in U-OAC and 3322 in I-OAC group. The U-OAC strategy increased over time, by 13% per year. Almost 80% of patients in both groups had an acute coronary syndrome. We found no major differences in terms of medical history, clinical characteristics and the CRUSADE bleeding score on admission. The proportion of patients on warfarin was higher in the I-OAC group (85 vs 81%). Patients in the I-OAC were more likely to receive low-molecular weight heparin (29 vs 12%) and glycoprotein IIb/IIIa inhibitors (6 vs 3%) during the index hospitalisation. In the I-OAC group, dual antiplatelet therapy without OAC was more often prescribed (22 vs 8%) and OAC plus single antiplatelet therapy was less often prescribed (8 vs 22%) at discharge. At 120 days, the cumulative rate of MACCE was 8.2 vs 8.2% and the rate of NACCE was 12.6 vs 12.9% in I-OAC vs U-OAC, respectively. We found no significant difference in the risk for MACCE and NACCE between the two groups (table). The risk for major or minor in-hospital bleeds was similar. I-OAC was associated with significantly longer time-delay to PCI and length of hospitalisation (table). Conclusion Uninterrupted OAC was safe and was associated with significantly shorter length of hospitalisation. Our data support U-OAC as the preferable strategy in patients on OAC undergoing PCI. Funding Acknowledgement Type of funding source: None

The use of interferon in medicine

Interferons are low-molecular weight glycoproteins. They are characterized by paracrine and autocrine activity. Their production and release occurs through various types of cells, which ultimately leads to the protection of the body against viral infections. Interferons do not have direct antiviral activity but affect cells, inducing the formation of antiviral agents and "antiviral readiness" in them. Thanks to their properties interferons have been widely used in the treatment of many diseases, among others hepatitis B, hepatitis C and multiple sclerosis. In addition, they show anti-cancer effects, even in the case of chronic myeloid leukemia. They are currently an important element in the search for a drug against SARS-CoV-2.

A biological overview of Hyaluronidase: A venom enzyme and its inhibition with plants materials

Snakebite is an enormous cause of mortality and morbidity especially in Asia, according to WHO snakebite, is very a common acute medical emergency in most rural, tribal, hilly areas of the tropical and subtropical countries. Snake venom is very complex mixture of enzymes like phospholipase A2, hyaluronidase, phosphomonoesterase, L-amino acid oxidase, acetylcholinesterase, phosphodiester, phosphomonoesterases, low molecular weight polypeptide, glycoprotein and metal ions. Hyaluronidase is one of the enzyme present in venoms of snake, leeches, scorpions, bees, caterpillars, spiders and in many others which acts as spreading factors and can cause local tissue damage like destruction of extracellular matrix and connective tissues. During envenomation, hyaluronidase activity is considered critical for the spreading of toxins and is supposed to change the integrity of extracellular matrix done by the degradation of hyaluronic acid in it. The compounds of plants which act as inhibitors are flavonoids, terpenoids, alkaloids, synthetic compounds, antioxidants, glycosaminoglycans, glycosides, oligosaccharides, polysaccharides, fatty acids, anti-inflammatory drugs and other reagents. Therefore, plants constituents can be effective inhibitors of enzymes like hyaluronidase and can be used as antivenom for venomous bite.The present review attempts to establish the structure isoforms, activity, mechanism and assay of hyaluronidase enzyme and their possible natural inhibitor for the inhibition of toxins spreading during envenomation.

Bleeding outcomes after non-emergency percutaneous coronary intervention in the very elderly.

BackgroundOctogenarians constitute an increasing proportion of patients presenting for non-emergency percutaneous coronary intervention (PCI).MethodsThis study evaluated the in-hospital procedural characteristics and outcomes, including the bleeding events of 293 octogenarians presenting between January 2010 and December 2012 for non-emergency PCI to a single large volume tertiary care Australian center. Comparisons were made with 293 consecutive patients aged less than or equal to 60 years, whose lesions were matched with the octogenarians.ResultsNon-ST elevation myocardial infarction was the most frequent indication for non-emergency PCI in octogenarians. Compared to the younger cohort, they had a higher prevalence of co-morbidities and more complex coronary disease, comprising more type C and calcified lesions. Peri-procedural use of low molecular weight heparin (LMWH; 1.0% vs. 5.8%; P < 0.001) and glycoprotein IIb/IIIa inhibitors (2.1% vs. 9.6%; P < 0.001) was lower, while femoral arterial access was used more commonly than in younger patients (80.9% vs. 67.6%; P < 0.001). Overall, there was a non-significant trend towards higher incidence of all bleeding events in the elderly (9.2% vs. 5.8%; P = 0.12). There was no significant difference in access site or non-access site bleeding and major or minor bleeding between the two cohorts. Sub-analysis did not reveal any significant influence on bleeding rates by the use of LMWH, glycoprotein IIb/IIIa inhibitors or femoral arterial access. In addition, there were no significant differences in the rates of in-hospital mortality, stroke or acute stent thrombosis between the two groups.ConclusionsIn this single center study, we did not observe significant increases in adverse in-hospital outcomes including the incidence of bleeding in octogenarians undergoing non-emergency PCI.

Regulation of IL-20 Expression by Estradiol through KMT2B-Mediated Epigenetic Modification.

Cytokines are low molecular weight regulatory proteins, or glycoproteins, with both tumor-promoting and inhibitory effects on breast cancer growth. Different cytokines play important roles in breast cancer initiation and progression. Here, we show that of the 39 interleukin (IL) genes, IL-20 is the only gene over-expressed in MCF-7 cells treated with estradiol (E2) and that induction of IL-20 expression by estrogen was epigenetically regulated. Methylation of histone H3K4 in the IL-20 promoter was shown to occur via the specific recruitment of KMT2B by estrogen receptor alpha (ERα), but not by other members of the mixed-lineage leukemia (MLL) family of histone methyltransferases. Depletion of KMT2B, or IL-20, disrupts estrogen signaling, attenuates cell proliferation, reduces colony formation, and results in cell cycle arrest. Furthermore, we demonstrated that KMT2B-mediated epigenetic modification also affected the expression of several ERα target genes. IL-20 and KMT2B expression were also associated with ERα-positive breast cancer tissues. We have revealed an important role for KMT2B in the epigenetic transcriptional regulation of cytokine IL-20, and other ERα-responsive genes, in breast cancer cells. Inhibition of IL-20 and KMT2B may have therapeutic benefits in ERα-positive breast cancer.

Purification and biochemical properties of multiple xylanases from Aspergillus ochraceus tolerant to Hg2+ ion and a wide range of pH.

Production of multiple xylanases, in which each enzyme has a specific characteristic, can be one strategy to achieve the effective hydrolysis of xylan. Three xylanases (xyl 1, xyl 2, and xyl 3) from Aspergillus ochraceus were purified by chromatography using diethylaminoethyl (DEAE) cellulose, Biogel P-60, and Sephadex G-100 columns. These enzymes are glycoproteins of low molecular weight with an optimum temperature at 60 °C. The glycosylation presented is apparently not related to thermostability, since xyl 3 (20 % carbohydrate) was more thermostable than xyl 2 (67 % carbohydrate). Xyl 3 was able to retain most of its activity in a wide range of pH (3.5-8.0), while xyl 1 and xyl 2 presented optimum pH of 6.0. Xyl 1 and xyl 2 were activated by 5 and 10 mM MnCl2 and CoCl2, while xyl 3 was activated by 1 mM of the same compounds. Interestingly, xyl 2 presented high tolerance toward mercury ion. Xylanases from A. ochraceus hydrolyzed xylans of different origins, such as birchwood, oat spelt, larchwood, and eucalyptus (around 90 % or more), except xyl 2 and xyl 3 that hydrolyzed with lesser efficiency eucalyptus (66.7 %) and oat spelt (44.8 %) xylans.

Does the Inhibition of the Final Common Pathway of Platelet Aggregation Reduce the No-Reflow Phenomenon During Primary Percutaneous Coronary Intervention? Tirofiban no Infarto Agudo do miocárdio e a não Reperfusão (TIARA)

ABSTRACT Background Primary percutaneous coronary intervention is currently the preferred method to treat patients with STsegment elevation acute myocardial infarction. The no-reflow phenomenon, which is the inability to reperfuse a region of the myocardium after restoration of patency of a previously occluded epicardial coronary artery, is observed in a considerable proportion of these patients. The benefit of IIb/IIIa glycoprotein inhibitors, blocking the final common pathway of platelet aggregation, has been suggested in studies of acute coronary syndromes, but their actual efficacy in the context of no-reflow in patients treated with primary percutaneous coronary intervention remains unclear. Methods The aim of this multicenter, double-blinded, placebo controlled study is to assess the impact of the early administration of the low molecular weight glycoprotein IIb/ IIIa inhibitor tirofiban on the incidence of no-reflow using angiographic and electrocardiographic methods to determine: (1) the epicardial coronary flow, using the TIMI score, and the microcirculatory flow, using the MBG score of opacification and myocardial flow; (2) the resolution of the ST segment elevation, as the final index of the success of reperfusion. Conclusions If the decrease in no-reflow incidence at 90 minutes and 24 hours after primary percutaneous coronary intervention is confirmed, this pilot study should guide the implementation of a larger study to investigate the possible impact of the systematic inhibition of the final common pathway of platelet aggregation on the mortality of ST-segment elevation acute myocardial infarction patients.

Mushrooms, their bioactive compounds and medicinal uses: A review

Medicinal mushrooms have been shown to have profound health promoting benefits viz., immunomodulation, anti-atherosclerotic, anti-inflammatory, analgesic, chemopreventive, antitumor, chemo and radio protective, sleep promoting, antibacterial, antiviral (including anti-HIV), hypolipidemic, hypoglycemic, anti-fibrotic, hepatoprotective, anti-diabetic, anti-androgenic, anti-angiogenic, anti-herpetic, antioxidative and radicalscavenging, anti-aging, estrogenic activity, anti-ulcer and many other exceptional nutritional and medicinal properties. Recent studies conducted all around the globe, are now confirming their medical efficacy and identifying many of the bioactive molecules (polysaccharides, tri-terpenoids, low molecular weight proteins, glycoproteins and immunomodulating compounds) which were not known to us earlier but recent advances in chemical technology have made it possible to isolate and purify some of these relevant compounds especially polysaccharides. The main medically important polysaccharides that have undergone extensive anticancer clinical trials include lentinan (Lentinula edodes), schizophyllan (Schizophyllum commune), PSK (polysaccharide-K, commercially sold as Krestin) and PSP (polysaccharopeptide) (Trametes versicolor), and Grifron-D (Grifola frondosa). All of these compounds are currently produced by Asian pharmaceutical companies. Methods of large-scale cultivation of many of the medicinal mushrooms by solid substrate and liquid culture fermentations are also available.

Role of interleukin-10 in breast cancer

Cytokines are low molecular weight regulatory proteins or glycoprotein that modulates the intensity and duration of immune response by stimulating or inhibiting the activation, proliferation, and/or differentiation of target cells. Different cytokines are known to have diverse role in breast cancer initiation and progression. Interleukin-10 (IL-10), a pleiotropic anti-inflammatory cytokine, induces immunosuppression and assists in escape from tumor immune surveillance. Like several other cytokines, IL-10 also can exert dual proliferative and inhibitory effect on breast tumor cells indicating a complex role of IL-10 in breast cancer initiation and progression. In this review, we tried to put together a comprehensive current view on significance of IL-10 in promotion, inhibition, and importance as prognosticator in breast cancer based on in vitro, in vivo, and clinical evidences. For literature collection, we conducted PubMed search with keywords "IL-10" and "breast cancer".

Perioperatives Management der antithrombotischen Behandlung bei Stent-Patienten

Perioperative management of antiplatelet treatment in patients with coronary stents remains challenging as premature discontinuation may cause thrombotic events. To date, there is a lack of evidence-based results and guidelines to recommend adequate antithrombotic drug therapy in patients at high risk of stent thrombosis who undergo noncardiac surgery. According to our clinical experience with these patients, we propose a perioperative bridging of discontinued dual antiplatelet therapy by the „off-label“ use of low molecular weight glycoprotein IIbIIIa antagonist for up to 24 hours. Patients should be monitored by a perioperative point-of-care-testing and, thus, could benefit from the individually adapted antiplatelet therapeutic issue.

The Saudi Project for Assessment of Coronary Events (SPACE) registry: Design and results of a phase I pilot study

The delay between the availability of clinical evidence and its application to the care of patients with acute coronary syndrome (ACS) in the Kingdom of Saudi Arabia remains undefined. The Saudi Project for Assessment of Coronary Events (SPACE) registry provides a comprehensive view of the current diagnostic and treatment strategies for patients with ACS; thus, the registry may be used to identify opportunities to improve the care of these patients. Eight hospitals in different regions of Saudi Arabia were involved in the pilot phase of the registry, from December 2005 to July 2006. The study patients included individuals with ST segment elevation myocardial infarction (STEMI), non-STEMI and unstable angina. A total of 435 patients (77% men and 80% Saudis) with a mean age of 57.1 years were enrolled. Medical history included previously diagnosed ischemic heart disease (32%), percutaneous coronary intervention (12%), diabetes mellitus (53%), hypertension (48%), current smoking (39%), hyperlipidemia (31%) and family history of premature coronary artery disease (11%). The median door-to-needle time for fibrinolytic therapy received by patients with STEMIs was 90 min. Inhospital medications included acetylsalicylic acid (98%), clopidogrel (73%), angiotensin- converting enzyme inhibitors (74%), beta-blockers (73%), statins (88%), unfractionated heparin (80%), low-molecular weight heparin (22%) and glycoprotein IIb/IIIa inhibitors (9%). The inhospital mortality rate was 5%. The first nationwide registry of patients with ACS in the Kingdom of Saudi Arabia is presented. In contrast to registries from developed countries, our cohort is characterized by a younger age at presentation and a much higher prevalence of diabetes mellitus. Most patients with STEMIs did not receive fibrinolytic therapy within the time recommended in the American College of Cardiology/American Heart Association guidelines. The results of the present pilot study show potential targets for improvement in care.

Campath 1-H treatment in patients with aggressive relapsing remitting multiple sclerosis

Campath 1-H (Alemtuzumab) is a humanised monoclonal antibody which targets the CD52 antigen, a low molecular weight glycoprotein present on the surface of most lymphocyte lineages, causing complement mediated lysis and rapid and prolonged T lymphocyte depletion. Following encouraging initial data from other centres we report our open label experience of using Campath 1-H as a treatment in aggressive relapsing multiple sclerosis in a consecutive series of 39 highly selected patients treated across three regional centres and followed for a mean of 1.89 years. The mean annualised relapse rate fell from 2.48 pre treatment to 0.19 post treatment with 29% of documented relapses observed in the 12 weeks following initial infusion. Mean change in EDSS was -0.36 overall and -0.15 in those patients completing > or =1 year of follow- up. Eighty-three per cent of patients had stable or improved disability following treatment. Infusion related side effects were common including rash, headache and pyrexia but were usually mild and self limiting. Transient worsening of pre-existing neurological deficits during infusion was observed in 3 patients. 12 patients developed biochemical evidence of autoimmune dysfunction, 2 patients developed thyroid disease and 1 patient autoimmune skin disease. We conclude that relapse rates fall following Campath 1-H. Whilst side effects were common these were normally self limiting or easily managed, suggesting Campath 1-H may be of use in the treatment of very active relapsing remitting multiple sclerosis.

A Novel Equation to Estimate Glomerular Filtration Rate Using Beta-Trace Protein

Beta-trace protein (BTP) is a low molecular weight glycoprotein that is a more sensitive marker of glomerular filtration rate (GFR) than serum creatinine. The utility of BTP has been limited by the lack of an equation to translate BTP into an estimate of GFR. The objectives of this study were to develop a BTP-based GFR estimation equation. We measured BTP and GFR by (99m)technetium-diethylenetriaminepentaacetic acid in 163 stable adult renal transplant recipients. Stepwise multiple regression models were created to predict GFR corrected for body surface area. The following variables were considered for entry into the model: BTP, urea, sex, albumin, creatinine, age, and race. BTP alone accounted for 75.6% of variability in GFR. The model that included all the predictor variables had the largest coefficient of determination (R(2)) at 0.821. The model with only BTP, urea, and sex had only a slightly lower R(2) of 0.81 and yielded the following equation: GFR mL . min(-1) . (1.73 m(2))(-1) = 112.1 x BTP(-0.662) x Urea(-0.280) x (0.88 if female). A 2nd equation (R(2) = 0.79) using creatinine instead of urea was also developed: GFR mL . min(-1) . (1.73 m(2))(-1) = 1.678 x BTP(-0.758) x creatinine(-0.204) x (0.871 if female). We have shown that BTP can be used in a simple equation to estimate GFR. Further study is needed in other populations to determine accuracy and clinical utility of this equation.

Shell matrices of Recent rhynchonelliform brachiopods: microstructures and glycosylation studies

ABSTRACTLike most metazoan biomineralisations, the brachiopod shell is the end product of a biologically controlled calcification process. The main agent of the control is the extracellular matrix, which is secreted by the outer mantle epithelium. This matrix mediates the calcification process by allowing crystal nucleation and elongation in specific orientations and finally, by stopping crystal growth. The proteinaceous moiety of brachiopod shell matrices has been extensively studied. Less known are the post-translational modifications that occur in these matrices, in particular glycosylations. In this comparison of five species of Recent articulated brachiopods, the ratio of soluble to insoluble organic matrix varies between the species. Polydisperse macromolecular materials occur in each of these species with discrete proteins of 50 kDa in Notosaria nigricans, Calloria inconspicua and Neothyris lenticularis, 37 kDa in Terebratulina retusa and Gryphus vitreus and 20–25 kDa in N. nigricans. Protein mixtures from all five species respond differently to anionic stains (Stains-All and Alcian Blue). PAS staining results in a positive smear in C. inconspicua and T. retusa and highlights low molecular weight glycoproteins in C. inconspicua. The polysaccharide composition of the soluble matrix of T. retusa is different from the others due to high proportions of arabinose and low proportions of fucose. In all cases, polysaccharide composition of the insoluble matrix is dominated by glucose and glucosamine. Insoluble matrices have more glucose and xylose and less galactosamine and glucosamine than the corresponding soluble matrix. Relatively high amounts of glucosamine may suggest the presence of chitin in the shell matrix of rhynchonelliform brachiopods.

Prehospital evaluation and treatment of a presumed acute coronary syndrome: what are the options?

The earlier infarct-limiting therapy is started the better is the outcome among patients suffering from a threatened myocardial infarction. The introduction of a prehospital electrocardiogram has improved triage of patients with acute chest pain. With regard to medication, fibrinolytic agents have the best documentation. Their use when frequently followed by a percutaneous coronary intervention at a later stage may be a good alternative among patients with ST-elevation myocardial infarction. Other treatments of potential value in the prehospital setting are oxygen, narcotic analgesics, nitrates, aspirin, heparin, low molecular weight heparin, glycoprotein IIB, IIIA blockers, clopidogrel and beta-blockers. We need further studies, however, for most of these treatments including cost-benefit analysis, analysis of various logistic aspects and safety in order to confirm their value.

Diffusion NMR studies on fish antifreeze proteins and synthetic analogues

Pulsed field gradient spin echo NMR spectroscopy was used to measure diffusion coefficients of the α-helical type I antifreeze protein from the winter flounder, two synthetic derivatives in which the four Thr residues were replaced with Val and Ala, respectively, and the low molecular weight fraction antifreeze glycoprotein. Under the conditions studied, the natural type I antifreeze protein and low molecular weight glycoprotein gave diffusion values that were consistent with the presence of monomeric protein in solution. While significant aggregation of the Ala analogue was observed (2–10 mM), there was no evidence for aggregation in the Val analogue (1–3 mM). These results are compared with previously reported solubility and thermal hysteresis data and the implications for the design of synthetic antifreeze proteins are discussed.