Low Molecular Weight Factor Research Articles

Poster 222: Venous Thromboembolism Risk factors and Prophylaxis Patterns in Knee Arthroscopy: A Large Database Study

Objectives:Incidence of venous thromboembolism (VTE) after knee arthroscopy is reportedly low, but rates vary significantly across literature. Current guidelines recommend against routine perioperative thromboprophylaxis, but prescribing practices and VTE risk factors are poorly understood.Methods:Medical records for patients ≥18 years of age were queried from the Pearl Diver database using CPT codes for arthroscopic knee procedures. Patients with a previous diagnosis of VTE or hyper-coagulable disorder were excluded from analyses. Procedures were grouped by rehabilitation protocols, with restrictive procedures requiring a period of non-weightbearing or postoperative immobilization. Patients who received perioperative thromboprophylaxis were identified. Patients diagnosed with VTE, including pulmonary embolism and/or deep vein thrombosis, within 90 days of surgery were identified using International Classification of Diseases (ICD) codes. Multivariable logistic regression models were utilized to identify VTE risk factors and likelihood of thromboprophylaxis prescription. Covariates included age, restrictive rehabilitation protocols, oral contraceptive pill (OCP) use, and medical comorbidities.Results:A total of 718,289 patients underwent knee arthroscopy from 2011 to 2020. 10,769 patients (1.5%) received perioperative thromboprophylaxis, including aspirin (n=5,353, 0.7%), low molecular weight heparin (n=4,563, 0.6%) and factor Xa inhibitors (n=947, 0.1%). A total of 7,618 patients (1.1%) experienced VTE. Perioperative prophylaxis was associated with decreased odds of experiencing VTE (adjusted odds ratio [aOR] = 0.64, 95% confidence interval [CI] = 0.51 to 0.79) (Table 1). Restrictive procedure type was associated with increased odds of experiencing VTE (aOR =1.42, 95% CI = 1.34 to 1.50) and receiving prophylaxis (aOR=1.95, 95% CI = 1.87 to 2.05). OCP use (aOR = 1.63, 95% CI = 1.37 to 1.91), renal disease (aOR = 1.33, 95% CI = 1.18 to 1.50) and congestive heart failure (aOR = 1.30, 95% CI = 1.13 to 1.49) were associated with increased odds of VTE. Tobacco use was associated with increased odds of VTE (aOR = 1.12, 95% CI 1.03 to 1.22), but decreased odds of receiving perioperative prophylaxis (aOR = 0.84, 95% CI 0.78 to 0.91). Malignancy was associated with increased odds of receiving prophylaxis (aOR = 1.18, 95% CI 1.09 to 1.29) but not with increased odds of VTE.Conclusions:Procedures with restrictive rehabilitation protocols, OCP use, renal disease, and congestive heart failure are associated with increased odds of VTE following knee arthroscopy. Conversely, the use of perioperative thromboprophylaxis is associated with significantly lower odds of VTE. Risk factors for postoperative VTE are not always correlated with increased likelihood of receiving perioperative thromboprophylaxis. Patients with a tobacco use history may be an at-risk population that can be better selected for thromboprophylaxis when clinically appropriate.Table 1.Multivariable Logistic Model of VTE and Perioperative Thromboprophylaxis Odds

Impact of Patent Foramen Ovale on Total Knee Arthroplasty Cerebrovascular Accident Perioperative Management.

Venous thromboembolism and ischemic stroke are major complications following total knee arthroplasty (TKA) and potentially are associated with a patent foramen ovale (PFO). Although this association has been shown in other surgical disciplines, it has not been demonstrated in patients undergoing TKA. This study was undertaken to determine whether patients with a PFO would have a significantly increased risk of cerebrovascular accident (CVA) following TKA. The Humana national database was used to identify TKA patients who were stratified by the presence of a PFO from 2007 to 2016. Ninety-day follow-up was used for the primary outcome of CVA. Potential confounding comorbidities also were investigated, including age, sex, anticoagulation, insurance type, arrhythmia, valvular disease, peripheral vascular disease, chronic kidney disease, and diabetes mellitus. Of 153,245 TKAs, a total of 2272 patients had strokes; 479 of these patients had a PFO. On multivariable analysis, PFO remained an independent predictor of CVA postoperatively (odds ratio, 3.824; 95% confidence interval, 2.614-5.406; P<.0001). Other significant comorbidities associated with CVA included arrhythmia, chronic kidney disease, diabetes mellitus, peripheral vascular disease, and coronary valve disease. Importantly, low-molecular weight heparin or factor Xa inhibitor administration postoperatively had a negative correlation with stroke (odds ratio, 0.762; 95% confidence interval, 0.663-0.871; P=.0001 and odds ratio, 0.749; 95% confidence interval, 0.628-0.885; P=.0009, respectively). The findings of the multivariable analysis indicate PFO is associated with early postoperative CVA within 90 days following TKA. If known preoperatively, appropriate referral should be made to a cardiologist for PFO management and anticoagulation to reduce the overall risk of stroke. [Orthopedics. 2020;43(3):e151-e158.].

T-Cell Activation by Low Molecular Weight Drugs and Factors That Influence Susceptibility to Drug Hypersensitivity.

Drug hypersensitivity reactions adversely affect treatment outcome, increase the length of patients' hospitalization, and limit the prescription options available to physicians. In addition, late stage drug attrition and the withdrawal of licensed drugs cost the pharmaceutical industry billions of dollars. This significantly increases the overall cost of drug development and by extension the price of licensed drugs. Drug hypersensitivity reactions are characterized by a delayed onset, and reactions tend to be more serious upon re-exposure. The role of drug-specific T-cells in the pathogenesis of drug hypersensitivity reactions and definition of the nature of the binding interaction of drugs with HLA and T-cell receptors continues to be the focus of intensive research, primarily because susceptibility is associated with expression of one or a small number of HLA alleles. This review critically examines the mechanisms of T-cell activation by drugs. Specific examples of drugs that activate T-cells via the hapten, the pharmacological interaction with immune receptors and the altered self-peptide repertoire pathways, are discussed. Furthermore, the impacts of drug metabolism, drug-protein adduct formation, and immune regulation on the development of drug antigen-responsive T-cells are highlighted. The knowledge gained from understanding the pathways of T-cell activation and susceptibility factors for drug hypersensitivity will provide the building blocks for the development of predictive in vitro assays that will prevent or help to minimize the incidence of these reactions in clinic.

Effect of double-filtration plasmapheresis for antibody-mediated rejection on hemostasis parameters and thrombin generation

IntroductionDonor-specific alloantibodies (DSAs) cause kidney-allograft loss in chronic antibody-mediated rejection (CAMR). Treatment relies on blocking antibody-producing cells and removing DSAs by apheresis: e.g., double-filtration plasmapheresis (DFPP). Materials and methodsTo determine the impact of DFPP (6 or 8 sessions/patient) on clotting factors and natural anticoagulants, and on thrombin generation, we performed a prospective and observational study in five CAMR kidney-transplant patients who received DFPP plus rituximab therapy. Thrombin generation was performed in poor platelet plasma (PPP) with 5 pM tissue factor without and with 2 nM recombinant human thrombomodulin. ResultsAfter the first DFPP session, median levels of high molecular-weight proteins (fibrinogen, FV, FVIII, FXI, FXIII, von Willebrand factors and α2-MG) decreased significantly to <50% of baseline values, whereas levels of low molecular-weight factors (<100 kDa) were not significantly modified, except for protein S and TFPI. Of note, binding-protein (BP) S, i.e., C4BP, was significantly decreased. Over the course of successive DFPP sessions, both high and lower molecular-weight proteins (<100 kDa) with longer half-lives (>2 days, prothrombin and factor XII) were significantly decreased. DFPP also highly affected thrombin generation in the absence of thrombomodulin but not significantly in the presence of thrombomodulin. After the first DFPP session, mean endogenous thrombin potential (ETP) and peak thrombin (PH) significantly decreased when the thrombin generation assay was performed without thrombomodulin (respectively, 1084 nM·min for ETP and 210 nM for PH after the first DFPP session compared to 1616 nM·min and 264 nM at baseline). In the presence of thrombomodulin, there was only a slight decrease in ETP and PH (respectively 748 nM·min, and 172 nM after the first DFPP session compared to 822 nM·min and 179 nM at baseline). After the last session, median ETP and PH decreased respectively to 646 nM·min and 143 nM without thrombomodulin, and, to 490 nM·min and 117 nM with thrombomodulin. ConclusionsDFPP significantly removed high molecular-weight proteins from the haemostatic system and profoundly decreased levels of protein S and TFPI. Overall thrombin-generation balance was only moderately affected in the presence of thrombomodulin. Nevertheless, high depletion of fibrinogen, FXIII and Von Willebrand Factor may expose patients to an increased risk of bleeding.

Proteinaceous sperm motility inhibitory factor from the female Indian garden lizard Calotes versicolor.

Female sperm storage is an intriguing adaptation exhibited by a wide array of both vertebrates and invertebrates. The mechanisms underlying female sperm storage have remained elusive. Using the Indian garden lizard Calotes versicolor as a model organism, we investigated the role of low and high molecular weight factors in this phenomenon. Previously, we demonstrated three distinct phases of the reproductive cycle in this animal with live, motile spermatozoa recovered from the uterovaginal region during the reproductive phase. In the present study, we analysed the uterovaginal contents using sodium dodecyl sulfate-polyacrylamide gel electrophoresis and identified an abundant protein band corresponding to ~55 kDa regardless of the phase of the reproductive cycle. Analysis of the purified protein by liquid chromatography-tandem mass spectrometry suggested a unique protein without any homology to the National Center for Biotechnology Information database. Exogenous addition of this protein to washed spermatozoa derived from the epididymis reversibly inhibited sperm motility in a concentration- and time-dependent manner, suggesting it plays a key role in sperm storage. These studies are likely to offer new avenues to unravel the secrets of female sperm storage seen across the animal taxa and may have novel applications not only in reproductive biology, but also in general cell storage and preserving endangered animal species.

OC-017 International Multicentre Study Assessing the Effects of Anti-Thrombotic Use in Patients with Upper GI Bleeding

Introduction Anti-thrombotics (antiplatelets and anticoagulants; ATs) have been identified as risk factors for upper gastrointestinal bleeding (UGIB). However few international studies have evaluated their effect on patient outcome. We aimed to assess the effects of AT use on outcome in patients with high-risk UGIB requiring endoscopic therapy. Methods Patients presenting with UGIB who required endoscopic therapy at eight centres (Scotland, England, USA, Canada, Denmark, Italy, Singapore & New Zealand) were prospectively included over 12 months. Data recorded included the full Rockall score (FRS); AT use (Aspirin, Adenosine Diphosphate Receptor Inhibitors (ADP-RI), Vitamin-K Antagonists (VKA), Low Molecular Weight Heparin (LMWH), Thrombin inhibitors and Factor Xa inhibitors); endoscopic findings; blood transfusion; interventional radiology; surgery; rebleeding; 30 day mortality and length of hospital stay. Results Out of 3154 patients, 619 required endotherapy (44% for ulcer bleeding and 21% for varices). 187 (30%) patients were on aspirin, 61 (11%) ADP-RI, 57 (9%) VKA, 8 (1%) LMWH, 7 (1%) factor Xa-inhibitor and 1 patient a thrombin-inhibitor. 63 (11%) patients were treated with >1 type of AT. Patients treated with ATs were older (p Conclusion Patients with UGIB who require endoscopic therapy whilst on ATs do not experience a higher rate of rebleeding or mortality compared with UGIB patients who do not use ATs. We observed excess mortality in patients not taking ATs, which is likely due to the high rates of cirrhosis (40%) and variceal bleeding (33%) in these patients. Further studies are needed to clarify the risk of adverse outcome following UGIB in patients taking novel ATs. Disclosure of Interest None Declared

Pollen derived low molecular compounds enhance the human allergen specific immune response invivo.

Besides allergens, pollen release bioactive, low molecular weight compounds that modulate and stimulate allergic reactions. Clinical relevance of these substances has not been investigated to date. To elucidate the effect of a non-allergenic, low molecular weight factors from aqueous birch pollen extracts (Bet-APE<3kDa) on the human allergic immune response invivo. Birch and grass pollen allergic individuals underwent skin prick testing with allergen alone, allergen plus Bet-APE<3kDa, or allergen plus pre-identified candidate substances from low molecular pollen fraction. Nasal allergen challenges were performed in non-atopic and pollen allergic individuals using a 3day repeated threshold challenge battery. Subjects were either exposed to allergen alone or to allergen plus Bet-APE<3kDa. Local cytokine levels, nasal secretion weights, nasal congestion and symptom scores were determined. Skin prick test reactions to pollen elicited larger weals when allergens were tested together with the low molecular weight compounds from pollen. Similar results were obtained with candidate pollen-associated lipid mediators. In nasal lining fluids of allergic patients challenged with allergen plus Bet-APE<3kDa, IL-8 and IgE was significantly increased as compared to allergen-only challenged patients. These patients also produced increased amounts of total nasal secretion and reported more severe rhinorrhea than the allergen-only challenged group. Low molecular compounds from pollen enhance the allergen specific immune response in the skin and nose. They are therefore of potential clinical relevance in allergic patients.

HIV-Enhancing Factors Are Secreted by Reproductive Epithelia upon Inoculation with Bacterial Vaginosis-Associated Bacteria.

Bacterial vaginosis is a common reproductive infection in which commensal vaginal lactobacilli are displaced by a mixed population of pathogenic bacteria. Bacterial vaginosis increases susceptibility to HIV, and it has been suggested that host innate immune responses to pathogenic bacteria contribute to enhanced infection, yet the cellular mechanisms mediating the increased HIV susceptibility remain uncharacterized. We evaluated the HIV-enhancing effects of bacterial vaginosis by inoculating endocervical epithelia with Atopobium vaginae, a bacterial vaginosis-associated bacteria, and assaying secreted factors for HIV-enhancing activity. When epithelia and A. vaginae were cocultured, we observed increased HIV-enhancing activity mediated by secreted low molecular weight factors. From this complex mixture we identified several upregulated host proteins, which functioned in combination to enhance HIV infection. These studies suggest that the host immune response to bacterial vaginosis-associated bacteria results in the release of HIV-enhancing factors. The combined activity of bacterial vaginosis-induced proteins likely mediates HIV enhancement.

Malachite green decolorization by the filamentous fungus Myrothecium roridum – Mechanistic study and process optimization

The filamentous fungus Myrothecium roridum isolated from a dye-contaminated area was investigated in terms of its use for the treatment of Malachite green (MG). The mechanisms involved in this process were established. Peroxidases and cytochrome P-450 do not mediate MG elimination. The laccase of M. roridum IM 6482 was found to be responsible for the decolorization of 8–11% of MG. Thermostable low-molecular-weight factors (LMWF) resistant to sodium azide were found to be largely involved in dye decomposition. In addition, MG decolorization by M. roridum IM 6482 occurred in a non-toxic manner. Data from antimicrobial tests showed that MG toxicity decreased after decolorization. To optimize the MG decolorization process, the effects of operational parameters (such as the medium pH and composition, process temperature and culture agitation) were examined. The results demonstrate that M. roridum IM 6482 may be used effectively as an alternative to traditional decolorization agents.

Do lipids influence the allergic sensitization process?

Allergic sensitization is a multifactorial process that is not only influenced by the allergen and its biological function per se but also by other small molecular compounds, such as lipids, that are directly bound as ligands by the allergen or are present in the allergen source. Several members of major allergen families bind lipid ligands through hydrophobic cavities or electrostatic or hydrophobic interactions. These allergens include certain seed storage proteins, Bet v 1–like and nonspecific lipid transfer proteins from pollens and fruits, certain inhalant allergens from house dust mites and cockroaches, and lipocalins. Lipids from the pollen coat and furry animals and the so-called pollen-associated lipid mediators are codelivered with the allergens and can modulate the immune responses of predisposed subjects by interacting with the innate immune system and invariant natural killer T cells. In addition, lipids originating from bacterial members of the pollen microbiome contribute to the outcome of the sensitization process. Dietary lipids act as adjuvants and might skew the immune response toward a TH2-dominated phenotype. In addition, the association with lipids protects food allergens from gastrointestinal degradation and facilitates their uptake by intestinal cells. These findings will have a major influence on how allergic sensitization will be viewed and studied in the future.

Activation of T7 RNA polymerase in Xenopus oocytes and cell‐free extracts

Single-subunit bacteriophage T7 RNA polymerase (T7 RNAP) is universally employed for in vivo and in vitro transcription of genes put under control of the T7 promoter. The enzyme is capable of transcribing a complete gene without additional proteins. In this study, we reveal the presence of a low molecular weight factor, which induces several-fold activation of T7 RNAP in the cytoplasm of oocytes and eggs from Xenopus laevis. Cell-free reconstitution of the T7 RNAP activation allowed us to investigate the molecular properties of the activator, establish its peptide nature and suggest T7 RNAP activation mechanism. In contrast to the previously described nonspecific transcriptional activators, which interact with scattered ionic sites on nucleic acids, the peptide activator associates with T7 RNAP molecule, thus being a bona fide activator of the polymerase. To our knowledge, this is the first report concerning the specific activation of T7 RNAP by a factor of peptide or protein origin. Besides rather obvious merits in gaining more efficient transcription with T7 RNAP, this finding can provide additional insights into regulatory mechanisms of transcription. The study also introduces a novel highly sensitive luminescent assay of T7 RNAP activity.

Cardioprotective effect of ornitho-kinin in an anesthetized, open-chest chicken model of acute coronary occlusion

The generation of bradykinin (BK; Arg-Pro-Pro-Gly-Phe-Ser-Pro-Phe-Arg) in blood and kallidin (Lys-BK) in tissues by the action of the kallikrein-kinin system has received little attention in non-mammalian vertebrates. In mammals, kallidin can be generated by the coronary endothelium and myocytes in response to ischemia, mediating cardioprotective events. The plasma of birds lacks two key components of the kallikrein-kinin system: the low molecular weight kininogen and a prekallikrein activator analogous to mammalian factor XII, but treatment with bovine plasma kallikrein generates ornitho-kinin [Thr6,Leu8]-BK. The possible cardioprotective effect of ornitho-kinin infusion was investigated in an anesthetized, open-chest chicken model of acute coronary occlusion. A branch of the left main coronary artery was reversibly ligated to produce ischemia followed by reperfusion, after which the degree of myocardial necrosis (infarct size as a percent of area at risk) was assessed by tetrazolium staining. The iv injection of a low dose of ornitho-kinin (4 microg/kg) reduced mean arterial pressure from 88 +/- 12 to 42 +/- 7 mmHg and increased heart rate from 335 +/- 38 to 402 +/- 45 bpm (N = 5). The size of the infarct was reduced by pretreatment with ornitho-kinin (500 microg/kg infused over a period of 5 min) from 35 +/- 3 to 10 +/- 2% of the area at risk. These results suggest that the physiological role of the kallikrein-kinin system is preserved in this animal model in spite of the absence of two key components, i.e., low molecular weight kininogen and factor XII.

Neuroprotection of microglial conditioned medium on 6‐hydroxydopamine‐induced neuronal death: role of transforming growth factor beta‐2

Microglia, the immune cells of the CNS, play essential roles in both physiological and pathological brain states. Here we have used an in vitro model to demonstrate neuroprotection of a 48 h-microglial conditioned medium (MCM) towards cerebellar granule neurons (CGNs) challenged with the neurotoxin 6-hydroxydopamine, which induces a Parkinson-like neurodegeneration, and to identify the protective factor(s). MCM nearly completely protects CGNs from 6-hydroxydopamine neurotoxicity and at least some of the protective factor(s) are peptidic in nature. While the fraction of the medium containing molecules < 30 kDa completely protects CGNs, fractions containing molecules < 10 kDa or > 10 kDa are not neuroprotective. We further demonstrate that microglia release high amounts of transforming growth factor-beta2 (TGF-beta2) and that its exogenous addition to the fraction of the medium not containing it (< 10 kDa) fully restores the neuroprotective action. Moreover, MCM neuroprotection is significantly counteracted by an inhibitor of TGF-beta2 transduction pathway. Our results identify TGF-beta2 as an essential neuroprotective factor released by microglia in its culture medium that requires to be fully effective the concomitant presence of other factor(s) of low molecular weight.

Astrocytes play a key role in activation of microglia by persistent Borna disease virus infection

Neonatal Borna disease virus (BDV) infection of the rat brain is associated with microglial activation and damage to certain neuronal populations. Since persistent BDV infection of neurons is nonlytic in vitro, activated microglia have been suggested to be responsible for neuronal cell death in vivo. However, the mechanisms of activation of microglia in neonatally BDV-infected rat brains remain unclear. Our previous studies have shown that activation of microglia by BDV in culture requires the presence of astrocytes as neither the virus nor BDV-infected neurons alone activate microglia. Here, we evaluated the mechanisms whereby astrocytes can contribute to activation of microglia in neuron-glia-microglia mixed cultures. We found that persistent infection of neuronal cells leads to activation of uninfected astrocytes as measured by elevated expression of RANTES. Activation of astrocytes then produces activation of microglia as evidenced by increased formation of round-shaped, MHCI-, MHCII- and IL-6-positive microglia cells. Our analysis of possible molecular mechanisms of activation of astrocytes and/or microglia in culture indicates that the mediators of activation may be soluble heat-resistant, low molecular weight factors. The findings indicate that astrocytes may mediate activation of microglia by BDV-infected neurons. The data are consistent with the hypothesis that microglia activation in the absence of neuronal damage may represent initial steps in the gradual neurodegeneration observed in brains of neonatally BDV-infected rats.

Keratinocyte-derived factors that stimulate fibroblast hyaluronan synthesis - the role of a low molecular weight factor

Hyaluronan-rich matrices are associated with cellular proliferation and migration, with high levels being expressed transiently during adult wound healing, and persistent high levels expressed during scar-free foetal wound healing. Cultured allogeneic keratinocytes and lysed keratinocyte extracts promote chronic wound healing, as does addition of exogenous hyaluronan. It is possible that the keratinocyte-stimulated effects on wound healing may be, at least in part mediated by the release of hyaluronan synthesis-stimulating factors. We have demonstrated that serum-free keratinocyte-conditioned medium (KCM), when added to confluent fibroblast cultures for 24 h stimulated up to an 8-fold increase in hyaluronan synthesis, as measured by 3H-glucosamine incorporation into cetylpyridinium chloride-precipitable glycosaminoglycans. This KCM can be fractionated by ultrafiltration into fractions > 30 kD and < 1 kD which are poorly active individually, but synergise strongly to stimulate fibroblast hyaluronan synthesis. We have examined the activity of both platelet-derived growth factor (PDGF) and basic fibroblast growth factor (bFGF) to stimulate fibroblast hyaluronan synthesis in the presence and absence of the low molecular weight KCM fraction, and the effect of blocking antibodies to PDGF and bFGF on complete KCM. KCM stimulated a 7-fold increase in 3H-glucosamine incorporation into hyaluronan and a 8.3-fold increase into sulphated glycosaminoglycans. 35SO4 incorporation was increased only 1.5-fold, resulting in a significant decrease in the degree of polymer sulphation of the sulphated glycosaminoglycans. Blocking antibodies to PDGF (all isotypes) reduced the activity of the KCM by 27%, while blocking antibFGF reduced the activity by 58%. Addition of PDGF (20 ng/ml) to the < 1 kD KCM fraction restored full activity, while addition of bFGF had no significant effect. However, addition of heparin with the bFGF resulted in activity being restored. These results demonstrate that cultured human keratinocytes produce potent fibroblast glycosaminoglycan synthesis-stimulating factors. Both PDGF and bFGF appear to be involved, but require the presence of an as yet unidentified KCM low molecular weight factor. Identification of this factor may provide an important therapeutic aid in wound healing

Beneficial effects of the thymic hormone preparation thymoxtimulin in patients with defects in cell-mediated immunity and chronic purulent rhinosinusitis. A double-blind cross-over trial on improvements in monocyte polarization and clinical effects

Twenty patients with chronic purulent rhinosinusitis were treated with TP-1 (Serono; 1 mg/kg body weight), in a double-blind cross-over trial. TP-1 was administered by daily i.m. injections for the first 14 days followed by two injections/week for 6 further weeks. The patients were immunologically special in that they had defects in their cell-mediated immune system. Fourteen showed a decreased chemotactic responsiveness of their peripheral blood monocytes as measured in the polarization assay. This defective function can probably be ascribed to the presence in serum of low molecular weight factors (LMWFs; less than 25 kD). As reported earlier, this factor shows a structural homology to the envelope protein of murine and feline leukaemia virus (P15E). Thirteen patients showed a defective delayed-type hypersensitivity (DTH) skin test reactivity towards candidin and/or streptokinase-streptodornase (Sk/Sd) antigen, 14 had a defective MIF production from their peripheral blood lymphocytes towards candidin, Sk/Sd and/or Haemophilus influenzae antigen. Eighteen patients completed the TP-1 trial and showed clinical improvements: 12 out of 15 were feeling better during TP-1 therapy and the nasal mucosa showed on inspection absent mucopurulent secretion in 13 patients. Positive bacterial culture rates for the nose decreased from 14 out of 16 to five out of 15. Placebo treatment had no significant effects. The clinical improvements were accompanied by a better performance of the cell-mediated immune system; the most significant effects were recorded in the monocyte polarization assay. The suppressive P15E-like LMWFs in serum clearly decreased during TP-1 treatment. In vitro TP-1 neutralized the immunosuppressive effect of the LMWFs. The restoring effects of TP-1 on monocyte polarization and its neutralizing activity of P15E-like LMWFs could explain the beneficial effects of thymic hormone treatment reported in adults with clinical signs of immunodeficiency in the presence of a full T cell repertoire.

Thromboembolic risk in the patient with heart failure

Although heart failure is a procoagulant state, the incidence of arterial thromboembolism (peripheral arterial emboli and strokes) is relatively low in the outpatient setting and seems to be higher in those with concomitant atrial fibrillation or recent large anterior myocardial infarction, especially in the presence of a dyskinetic apex. Hospitalized heart failure patients, on the other hand, have an extremely high rate of deep venous thrombosis and pulmonary emboli. Outpatients with heart failure should receive anticoagulation only in the presence of atrial fibrillation or if they have experienced a prior embolic event. Patients with recent large anterior infarction or recent infarction with documented thrombus should be treated with anticoagulation for the initial 3 months after the infarct, whereas those with evidence of a mural thrombus should receive anticoagulation at least until the thrombus has resolved. Heart failure patients with ischemic cardiomyopathy should receive antiplatelet agents for the prevention of myocardial infarction, stroke, or death. Antiplatelet agents should not be prescribed for heart failure patients with nonischemic cardiomyopathy or without other evidence of atherosclerotic vascular disease. All hospitalized heart failure patients who are not taking oral anticoagulants should receive prophylaxis with low molecular weight heparins or factor Xa inhibitors.

Smoke treatment triggers the release of a novel DNA damaging factor by lymphocytes

Organic fuel smoke is a hazardous agent, which pushes the cells towards"prooxidant state'', leading to 4,46,400 strand breaks/cell/day as against 47,000 strand breaks/cell/day produced by constitutive oxygen radicals. This prooxidants scenario switches on a plethora of intercellular events. Here we report a novel DNA damaging factor released by lymphocytes, upon treatment with smoke condensate. Human lymphocytes, when exposed to cow dung cake smoke condensate, were found to release a low molecular weight factor into the media at 20 min of exposure. The conditioned media, displayed a propensity of inducing DNA damage in fresh, normal lymphocytes, which were not exposed to any damaging agent. The above DNA damaging effect of the conditioned media was not due to any residual presence of Polycyclic Aromatic Hydrocarbons, which were present in the smoke. The release of this factor was in correlation with the DNA damaging event, taking place in the cells. This secondary DNA damaging factor had a molecular weight less than 5 kd. The factor had the cell death inducing propensity when allowed to act on lymphocytes.

Identification of differentiation-inducing activity produced by human bone marrow stromal cell line LP101

We have previously reported that human promyelocytic leukemia HL-60 cells can be induced to differentiate into mature granulocytes when HL-60 co-cultivated with human bone marrow stromal LP101 cells. In the present study, we investigated which factors produced by LP101 cells induce HL-60 cells to differentiate into mature granulocytes. The expression of the cell surface antigen CD11b on HL-60 cells was increased after a 72-h culture with the conditioned medium (CM) obtained from LP101 cells. LP101 cells were observed to produce various cytokines, including TNF-alpha, GM-CSF and IL-6. The neutralizing antibodies against these cytokines partially suppressed the CM-induced differentiation of HL-60 cells. Recombinant TNF-alpha induced the differentiation of HL-60 cells, and GM-CSF and IL-6 additionally enhanced the effect of TNF-alpha. When the CM was divided into a low molecular weight (LMW) fraction and a high molecular weight (HMW) fraction by ultrafiltration, the LMW fraction synergistically enhanced the differentiation inducible activity of TNF-alpha. These results demonstrate that LP101 cells induce the differentiation of HL-60 cells by producing various cytokines including TNF-alpha, IL-6, and GM-CSF, and that unknown low molecular weight factors also participate.

Efficient Incorporation of Eukaryotic Initiation Factor 1 into the Multifactor Complex Is Critical for Formation of Functional Ribosomal Preinitiation Complexes in Vivo

Eukaryotic initiation factor 1 (eIF1) is a low molecular weight factor critical for stringent AUG selection in eukaryotic translation. It is recruited to the 43 S complex in the multifactor complex (MFC) with eIF2, eIF3, and eIF5 via multiple interactions with the MFC constituents. Here we show that FLAG epitope tagging of eIF1 at either terminus abolishes its in vitro interactions with eIF5 and eIF2beta but not that with eIF3c. Nevertheless, both forms of FLAG-eIF1 fail to bind eIF3 and are incorporated into the 43 S complex inefficiently in vivo. C-terminal FLAG tagging of eIF1 is lethal; overexpression of C-terminal FLAG-eIF1 severely impedes 43 S complex formation and derepresses GCN4 translation due to limiting of eIF2.GTP.Met-tRNA(i)(Met) ternary complex binding to the ribosome. Furthermore, N-terminal FLAG-eIF1 overexpression reduces eIF2 binding to the ribosome and moderately derepresses GCN4 translation. Our results provide the first in vivo evidence that eIF1 plays an important role in promoting 43 S complex formation as a core of factor interactions. We propose that the coordinated recruitment of eIF1 to the 40 S ribosome in the MFC is critical for the production of functional 40 S preinitiation complex.