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  1. Alexander NJ, Clarkson TB, Fulgham DL
    Lab. Anim. Sci., 1985 Oct;35(5):465-8.
    PMID: 4057940
    Nonhuman primates can be used as models for the study of immune-complex-associated diseases. Recognizing that very little is known about the levels of circulating immune complexes (CICs) in normal monkeys, we have used three assays to measure the levels in serum collected from 313 adult and 106 juvenile cynomolgus macaques (Macaca fascicularis). The prevalence was higher than expected. There was a strong statistical association between CIC levels and country of origin. Monkeys from Indonesia were more likely to have elevated CICs than those from Malaya or the Philippines. This relationship was observed with all three assays. Furthermore, juvenile macaques tended to have lower levels than did adults. This study indicates that it may be important to consider genetic factors, the country of origin, or both when selecting cynomolgus macaques for research on immune-complex-associated diseases.
  2. Topchii II, Kirienko AN, Kirienko DA, Yakovtsova II, Gavriluk AA, Danyliuk SV, et al.
    Wiad Lek, 2019;72(7):1269-1273.
    PMID: 31398154
    OBJECTIVE: Introduction: Vascular endothelium function interruption has the main role among mechanisms of development and progression of chronic kidney disease. In numerous experimental and clinical studies, it was proved that activated vascular endothelium is a structural and functional unit that matches processes of inflammation with intravascular coagulation, fibrinolysis and haemorheological disorders. The aim: To identify special features of endothelium morphological structure in kidney vessels, coronary arteries and aorta during chronic kidney disease.

    PATIENTS AND METHODS: Materials and methods: Based on autopsy materials, we conducted a morphological study of patients (n = 20) aged 45 to 55 years who were observed in cardiac and neurological hospitals for 5-7 years. We removed kidney, heart and aorta samples from patients. For the study, a histological and immunohistochemical methods were used.

    RESULTS: Results and conclusions: Morphological study of vessels endothelium of kidneys, heart and aorta demonstrated that in the majority of observations intima underwentprofound pathological changes, manifested by different degrees of disorganization of endothelial lining and violations of structural and functional organization of the endotheliocytes, subendothelial layer, basal membrane. These pathological processes in all cases had similar features with the development of immune inflammation. Inflammatory infiltration was represented by macrophages, mast cells, plasma cells. Biological mediators of the presented cells can aggravate the damage to endothelial cells. Indirect signs of low ability to restore the structure of the vessel wall and endothelial lining may be a weak expression of the VEGF and bcl-2 vascular endothelial growth factor.

  3. Rosenberger KD, Lum L, Alexander N, Junghanss T, Wills B, Jaenisch T, et al.
    Trop Med Int Health, 2016 Mar;21(3):445-53.
    PMID: 26752720 DOI: 10.1111/tmi.12666
    OBJECTIVE: Clinical management of dengue relies on careful monitoring of fluid balance combined with judicious intravenous (IV) fluid therapy. However, in patients with significant vascular leakage, IV fluids may aggravate serosal fluid accumulation and result in respiratory distress.
    METHODS: Trained physicians followed suspected dengue cases prospectively at seven hospitals across Asia and Latin America, using a comprehensive case report form that included daily clinical assessment and detailed documentation of parenteral fluid therapy. Applying Cox regression, we evaluated risk factors for the development of shock or respiratory distress with fluid accumulation.
    RESULTS: Most confirmed dengue patients (1524/1734, 88%) never experienced dengue shock syndrome (DSS). Among those with DSS, 176/210 (84%) had fluid accumulation, and in the majority (83%), this was detectable clinically. Among all cases with clinically detectable fluid accumulation, 179/447 (40%) were diagnosed with shock or respiratory distress. The risk for respiratory distress with fluid accumulation increased significantly as the infused volume over the preceding 24 h increased (hazard ratio 1.18 per 10 ml/kg increase; P < 0.001). Longer duration of IV therapy, use of a fluid bolus in the preceding 24 h, female gender and poor nutrition also constituted independent risk factors.
    CONCLUSIONS: Shock and respiratory distress are relatively rare manifestations of dengue, but some evidence of fluid accumulation is seen in around 50% of cases. IV fluids play a crucial role in management, but they must be administered with caution. Clinically and/or radiologically detectable fluid accumulations have potential as intermediate severity endpoints for therapeutic intervention trials and/or pathogenesis studies.
    KEYWORDS: IV fluid therapy; clinical spectrum; dengue; espectro clínico; fluidothérapie IV; fuga vascular; fuite vasculaire; prospectif; prospective; prospectivo; spectre clinique; terapia IV de fluidos; vascular leakage
  4. Escaffre O, Hill T, Ikegami T, Juelich TL, Smith JK, Zhang L, et al.
    J Infect Dis, 2018 10 05;218(10):1602-1610.
    PMID: 29912426 DOI: 10.1093/infdis/jiy357
    Background: Nipah virus (NiV) is a paramyxovirus (genus Henipavirus) that can cause severe respiratory illness and encephalitis in humans. Transmission occurs through consumption of NiV-contaminated foods, and contact with NiV-infected animals or human body fluids. However, it is unclear whether aerosols derived from aforesaid sources or others also contribute to transmission, and current knowledge on NiV-induced pathogenicity after small-particle aerosol exposure is still limited.

    Methods: Infectivity, pathogenicity, and real-time dissemination of aerosolized NiV in Syrian hamsters was evaluated using NiV-Malaysia (NiV-M) and/or its recombinant expressing firefly luciferase (rNiV-FlucNP).

    Results: Both viruses had an equivalent pathogenicity in hamsters, which developed respiratory and neurological symptoms of disease, similar to using intranasal route, with no direct correlations to the dose. We showed that virus replication was predominantly initiated in the lower respiratory tract and, although delayed, also intensely in the oronasal cavity and possibly the brain, with gradual increase of signal in these regions until at least day 5-6 postinfection.

    Conclusion: Hamsters infected with small-particle aerosolized NiV undergo similar clinical manifestations of the disease as previously described using liquid inoculum, and exhibit histopathological lesions consistent with NiV patient reports. NiV droplets could therefore play a role in transmission by close contact.

  5. Covés-Datson EM, King SR, Legendre M, Swanson MD, Gupta A, Claes S, et al.
    Sci Rep, 2021 01 12;11(1):656.
    PMID: 33436903 DOI: 10.1038/s41598-020-80577-7
    Lectins, carbohydrate-binding proteins, have been regarded as potential antiviral agents, as some can bind glycans on viral surface glycoproteins and inactivate their functions. However, clinical development of lectins has been stalled by the mitogenicity of many of these proteins, which is the ability to stimulate deleterious proliferation, especially of immune cells. We previously demonstrated that the mitogenic and antiviral activities of a lectin (banana lectin, BanLec) can be separated via a single amino acid mutation, histidine to threonine at position 84 (H84T), within the third Greek key. The resulting lectin, H84T BanLec, is virtually non-mitogenic but retains antiviral activity. Decreased mitogenicity was associated with disruption of pi-pi stacking between two aromatic amino acids. To examine whether we could provide further proof-of-principle of the ability to separate these two distinct lectin functions, we identified another lectin, Malaysian banana lectin (Malay BanLec), with similar structural features as BanLec, including pi-pi stacking, but with only 63% amino acid identity, and showed that it is both mitogenic and potently antiviral. We then engineered an F84T mutation expected to disrupt pi-pi stacking, analogous to H84T. As predicted, F84T Malay BanLec (F84T) was less mitogenic than wild type. However, F84T maintained strong antiviral activity and inhibited replication of HIV, Ebola, and other viruses. The F84T mutation disrupted pi-pi stacking without disrupting the overall lectin structure. These findings show that pi-pi stacking in the third Greek key is a conserved mitogenic motif in these two jacalin-related lectins BanLec and Malay BanLec, and further highlight the potential to rationally engineer antiviral lectins for therapeutic purposes.
  6. Fornace KM, Abidin TR, Alexander N, Brock P, Grigg MJ, Murphy A, et al.
    Emerg Infect Dis, 2016 Feb;22(2):201-8.
    PMID: 26812373 DOI: 10.3201/eid2202.150656
    The zoonotic malaria species Plasmodium knowlesi has become the main cause of human malaria in Malaysian Borneo. Deforestation and associated environmental and population changes have been hypothesized as main drivers of this apparent emergence. We gathered village-level data for P. knowlesi incidence for the districts of Kudat and Kota Marudu in Sabah state, Malaysia, for 2008-2012. We adjusted malaria records from routine reporting systems to reflect the diagnostic uncertainty of microscopy for P. knowlesi. We also developed negative binomial spatial autoregressive models to assess potential associations between P. knowlesi incidence and environmental variables derived from satellite-based remote-sensing data. Marked spatial heterogeneity in P. knowlesi incidence was observed, and village-level numbers of P. knowlesi cases were positively associated with forest cover and historical forest loss in surrounding areas. These results suggest the likelihood that deforestation and associated environmental changes are key drivers in P. knowlesi transmission in these areas.
  7. Rosenberger KD, Alexander N, Martinez E, Lum LCS, Dempfle CE, Junghanss T, et al.
    PLoS Negl Trop Dis, 2020 Mar;14(3):e0008076.
    PMID: 32130212 DOI: 10.1371/journal.pntd.0008076
    Severe dengue was perceived as one clinical disease entity until the WHO 2009 classification stratified it into severe vascular leakage, severe bleeding, and severe organ dysfunction. The objectives of this study were to investigate the potential use of severe dengue categories as endpoints for intervention research. 271 patients with severe dengue among 1734 confirmed dengue patients were followed prospectively in this hospital-based observational study in Latin America and Asia. We compared the distribution of severe dengue categories according to gender and age (below/above 15y), and determined the relative frequency and the overlap of severe dengue categories in the same patients. In a next step, we extended the analysis to candidate moderate severity categories, based on recently suggested definitions which were adapted for our purposes. Severe vascular leakage occurred in 244 (90%), severe bleeding in 39 (14%), and severe organ dysfunction in 28 (10%) of 271 severe dengue patients. A higher frequency of severe leakage was seen in children or adolescents (<15y) compared to adults. More than 80% of the severe leakage cases, and 30-50% of the cases with severe bleeding or severe organ dysfunction, were defined as severe on the basis of that feature alone. In 136 out of 213 patients with severe leakage alone, neither moderate bleeding manifestation nor hepatic involvement was recorded. On the other hand, moderate leakage manifestations were detected in 4 out of 12 cases that were classified as severe based on bleeding alone. A major proportion of severe dengue patients exhibited clinical manifestations of severe vascular leakage only, which may constitute a useful endpoint for intervention research or pathophysiology studies. Severe bleeding and severe organ manifestation were recorded less frequently and exhibited a higher degree of overlap with severe leakage. Severe bleeding without leakage may be associated with individual predisposition or the presence of comorbidities. More detailed assessments are needed to explore this hypothesis. Candidate moderate disease endpoints were investigated and need to be further validated.
  8. Saadatian-Elahi M, Alexander N, Möhlmann T, Langlois-Jacques C, Suer R, Ahmad NW, et al.
    Trials, 2021 May 30;22(1):374.
    PMID: 34053466 DOI: 10.1186/s13063-021-05298-2
    BACKGROUND: In common with many South East Asian countries, Malaysia is endemic for dengue. Dengue control in Malaysia is currently based on reactive vector management within 24 h of a dengue case being reported. Preventive rather than reactive vector control approaches, with combined interventions, are expected to improve the cost-effectiveness of dengue control programs. The principal objective of this cluster randomized controlled trial is to quantify the effectiveness of a preventive integrated vector management (IVM) strategy on the incidence of dengue as compared to routine vector control efforts.

    METHODS: The trial is conducted in randomly allocated clusters of low- and medium-cost housing located in the Federal Territory of Kuala Lumpur and Putrajaya. The IVM approach combines: targeted outdoor residual spraying with K-Othrine Polyzone, deployment of mosquito traps as auto-dissemination devices, and community engagement activities. The trial includes 300 clusters randomly allocated in a 1:1 ratio. The clusters receive either the preventive IVM in addition to the routine vector control activities or the routine vector control activities only. Epidemiological data from monthly confirmed dengue cases during the study period will be obtained from the Vector Borne Disease Sector, Malaysian Ministry of Health e-Dengue surveillance system. Entomological surveillance data will be collected in 12 clusters randomly selected from each arm. To measure the effectiveness of the IVM approach on dengue incidence, a negative binomial regression model will be used to compare the incidence between control and intervention clusters. To quantify the effect of the interventions on the main entomological outcome, ovitrap index, a modified ordinary least squares regression model using a robust standard error estimator will be used.

    DISCUSSION: Considering the ongoing expansion of dengue burden in Malaysia, setting up proactive control strategies is critical. Despite some limitations of the trial such as the use of passive surveillance to identify cases, the results will be informative for a better understanding of effectiveness of proactive IVM approach in the control of dengue. Evidence from this trial may help justify investment in preventive IVM approaches as preferred to reactive case management strategies.

    TRIAL REGISTRATION: ISRCTN ISRCTN81915073 . Retrospectively registered on 17 April 2020.

  9. Fornace KM, Alexander N, Abidin TR, Brock PM, Chua TH, Vythilingam I, et al.
    Elife, 2019 10 22;8.
    PMID: 31638575 DOI: 10.7554/eLife.47602
    Human movement into insect vector and wildlife reservoir habitats determines zoonotic disease risks; however, few data are available to quantify the impact of land use on pathogen transmission. Here, we utilise GPS tracking devices and novel applications of ecological methods to develop fine-scale models of human space use relative to land cover to assess exposure to the zoonotic malaria Plasmodium knowlesi in Malaysian Borneo. Combining data with spatially explicit models of mosquito biting rates, we demonstrate the role of individual heterogeneities in local space use in disease exposure. At a community level, our data indicate that areas close to both secondary forest and houses have the highest probability of human P. knowlesi exposure, providing quantitative evidence for the importance of ecotones. Despite higher biting rates in forests, incorporating human movement and space use into exposure estimates illustrates the importance of intensified interactions between pathogens, insect vectors and people around habitat edges.
  10. Moayyedi P, Eikelboom JW, Bosch J, Connolly SJ, Dyal L, Shestakovska O, et al.
    Gastroenterology, 2019 08;157(2):403-412.e5.
    PMID: 31054846 DOI: 10.1053/j.gastro.2019.04.041
    BACKGROUND & AIMS: Antiplatelets and anticoagulants are associated with increased upper gastrointestinal bleeding. We evaluated whether proton pump inhibitor therapy could reduce this risk.

    METHODS: We performed a 3 × 2 partial factorial double-blind trial of 17,598 participants with stable cardiovascular disease and peripheral artery disease. Participants were randomly assigned to groups given pantoprazole 40 mg daily or placebo, as well as rivaroxaban 2.5 mg twice daily with aspirin 100 mg once daily, rivaroxaban 5 mg twice daily, or aspirin 100 mg alone. The primary outcome was time to first upper gastrointestinal event, defined as a composite of overt bleeding, upper gastrointestinal bleeding from a gastroduodenal lesion or of unknown origin, occult bleeding, symptomatic gastroduodenal ulcer or ≥5 erosions, upper gastrointestinal obstruction, or perforation.

    RESULTS: There was no significant difference in upper gastrointestinal events between the pantoprazole group (102 of 8791 events) and the placebo group (116 of 8807 events) (hazard ratio, 0.88; 95% confidence interval [CI], 0.67-1.15). Pantoprazole significantly reduced bleeding of gastroduodenal lesions (hazard ratio, 0.52; 95% confidence interval, 0.28-0.94; P = .03); this reduction was greater when we used a post-hoc definition of bleeding gastroduodenal lesion (hazard ratio, 0.45; 95% confidence interval, 0.27-0.74), although the number needed to treat still was high (n = 982; 95% confidence interval, 609-2528).

    CONCLUSIONS: In a randomized placebo-controlled trial, we found that routine use of proton pump inhibitors in patients receiving low-dose anticoagulation and/or aspirin for stable cardiovascular disease does not reduce upper gastrointestinal events, but may reduce bleeding from gastroduodenal lesions. ClinicalTrials.gov ID: NCT01776424.

  11. Moayyedi P, Eikelboom JW, Bosch J, Connolly SJ, Dyal L, Shestakovska O, et al.
    Gastroenterology, 2019 09;157(3):682-691.e2.
    PMID: 31152740 DOI: 10.1053/j.gastro.2019.05.056
    BACKGROUND & AIMS: Proton pump inhibitors (PPIs) are effective at treating acid-related disorders. These drugs are well tolerated in the short term, but long-term treatment was associated with adverse events in observational studies. We aimed to confirm these findings in an adequately powered randomized trial.

    METHODS: We performed a 3 × 2 partial factorial double-blind trial of 17,598 participants with stable cardiovascular disease and peripheral artery disease randomly assigned to groups given pantoprazole (40 mg daily, n = 8791) or placebo (n = 8807). Participants were also randomly assigned to groups that received rivaroxaban (2.5 mg twice daily) with aspirin (100 mg once daily), rivaroxaban (5 mg twice daily), or aspirin (100 mg) alone. We collected data on development of pneumonia, Clostridium difficile infection, other enteric infections, fractures, gastric atrophy, chronic kidney disease, diabetes, chronic obstructive lung disease, dementia, cardiovascular disease, cancer, hospitalizations, and all-cause mortality every 6 months. Patients were followed up for a median of 3.01 years, with 53,152 patient-years of follow-up.

    RESULTS: There was no statistically significant difference between the pantoprazole and placebo groups in safety events except for enteric infections (1.4% vs 1.0% in the placebo group; odds ratio, 1.33; 95% confidence interval, 1.01-1.75). For all other safety outcomes, proportions were similar between groups except for C difficile infection, which was approximately twice as common in the pantoprazole vs the placebo group, although there were only 13 events, so this difference was not statistically significant.

    CONCLUSIONS: In a large placebo-controlled randomized trial, we found that pantoprazole is not associated with any adverse event when used for 3 years, with the possible exception of an increased risk of enteric infections. ClinicalTrials.gov Number: NCT01776424.

  12. Eikelboom JW, Connolly SJ, Bosch J, Dagenais GR, Hart RG, Shestakovska O, et al.
    N Engl J Med, 2017 10 05;377(14):1319-1330.
    PMID: 28844192 DOI: 10.1056/NEJMoa1709118
    BACKGROUND: We evaluated whether rivaroxaban alone or in combination with aspirin would be more effective than aspirin alone for secondary cardiovascular prevention.

    METHODS: In this double-blind trial, we randomly assigned 27,395 participants with stable atherosclerotic vascular disease to receive rivaroxaban (2.5 mg twice daily) plus aspirin (100 mg once daily), rivaroxaban (5 mg twice daily), or aspirin (100 mg once daily). The primary outcome was a composite of cardiovascular death, stroke, or myocardial infarction. The study was stopped for superiority of the rivaroxaban-plus-aspirin group after a mean follow-up of 23 months.

    RESULTS: The primary outcome occurred in fewer patients in the rivaroxaban-plus-aspirin group than in the aspirin-alone group (379 patients [4.1%] vs. 496 patients [5.4%]; hazard ratio, 0.76; 95% confidence interval [CI], 0.66 to 0.86; P<0.001; z=-4.126), but major bleeding events occurred in more patients in the rivaroxaban-plus-aspirin group (288 patients [3.1%] vs. 170 patients [1.9%]; hazard ratio, 1.70; 95% CI, 1.40 to 2.05; P<0.001). There was no significant difference in intracranial or fatal bleeding between these two groups. There were 313 deaths (3.4%) in the rivaroxaban-plus-aspirin group as compared with 378 (4.1%) in the aspirin-alone group (hazard ratio, 0.82; 95% CI, 0.71 to 0.96; P=0.01; threshold P value for significance, 0.0025). The primary outcome did not occur in significantly fewer patients in the rivaroxaban-alone group than in the aspirin-alone group, but major bleeding events occurred in more patients in the rivaroxaban-alone group.

    CONCLUSIONS: Among patients with stable atherosclerotic vascular disease, those assigned to rivaroxaban (2.5 mg twice daily) plus aspirin had better cardiovascular outcomes and more major bleeding events than those assigned to aspirin alone. Rivaroxaban (5 mg twice daily) alone did not result in better cardiovascular outcomes than aspirin alone and resulted in more major bleeding events. (Funded by Bayer; COMPASS ClinicalTrials.gov number, NCT01776424 .).

  13. Bosch J, Eikelboom JW, Connolly SJ, Bruns NC, Lanius V, Yuan F, et al.
    Can J Cardiol, 2017 08;33(8):1027-1035.
    PMID: 28754388 DOI: 10.1016/j.cjca.2017.06.001
    BACKGROUND: Long-term aspirin prevents vascular events but is only modestly effective. Rivaroxaban alone or in combination with aspirin might be more effective than aspirin alone for vascular prevention in patients with stable coronary artery disease (CAD) or peripheral artery disease (PAD). Rivaroxaban as well as aspirin increase upper gastrointestinal (GI) bleeding and this might be prevented by proton pump inhibitor therapy.

    METHODS: Cardiovascular Outcomes for People Using Anticoagulation Strategies (COMPASS) is a double-blind superiority trial comparing rivaroxaban 2.5 mg twice daily combined with aspirin 100 mg once daily or rivaroxaban 5 mg twice daily vs aspirin 100 mg once daily for prevention of myocardial infarction, stroke, or cardiovascular death in patients with stable CAD or PAD. Patients not taking a proton pump inhibitor were also randomized, using a partial factorial design, to pantoprazole 40 mg once daily or placebo. The trial was designed to have at least 90% power to detect a 20% reduction in each of the rivaroxaban treatment arms compared with aspirin and to detect a 50% reduction in upper GI complications with pantoprazole compared with placebo.

    RESULTS: Between February 2013 and May 2016, we recruited 27,395 participants from 602 centres in 33 countries; 17,598 participants were included in the pantoprazole vs placebo comparison. At baseline, the mean age was 68.2 years, 22.0% were female, 90.6% had CAD, and 27.3% had PAD.

    CONCLUSIONS: COMPASS will provide information on the efficacy and safety of rivaroxaban, alone or in combination with aspirin, in the long-term management of patients with stable CAD or PAD, and on the efficacy and safety of pantoprazole in preventing upper GI complications in patients receiving antithrombotic therapy.

  14. Eikelboom JW, Bosch J, Connolly SJ, Tyrwitt J, Fox KAA, Muehlhofer E, et al.
    Eur Heart J Cardiovasc Pharmacother, 2022 Dec 02;8(8):786-795.
    PMID: 35383832 DOI: 10.1093/ehjcvp/pvac023
    AIMS: To describe outcomes of patients with chronic coronary artery disease (CAD) and/or peripheral artery disease (PAD) enrolled in the Cardiovascular Outcomes for People Using Anticoagulation Strategies (COMPASS) randomized trial who were treated with the combination of rivaroxaban 2.5 mg twice daily and aspirin 100 mg once daily during long-term open-label extension (LTOLE).

    METHODS AND RESULTS: Of the 27 395 patients enrolled in COMPASS, 12 964 (mean age at baseline 67.2 years) from 455 sites in 32 countries were enrolled in LTOLE and treated with the combination of rivaroxaban and aspirin for a median of 374 additional days (range 1-1191 days). During LTOLE, the incident events per 100 patient years were as follows: for the primary outcome [cardiovascular death, stroke, or myocardial infarction (MI)] 2.35 [95% confidence interval (CI) 2.11-2.61], mortality 1.87 (1.65-2.10), stroke 0.62 (0.50-0.76), and MI 1.02 (0.86-1.19), with CIs that overlapped those seen during the randomized treatment phase with the combination of rivaroxaban and aspirin. The incidence rates for major and minor bleeding were 1.01 (0.86-1.19) and 2.49 (2.24-2.75), compared with 1.67 (1.48-1.87) and 5.11 (95% CI 4.77-5.47), respectively, during the randomized treatment phase with the combination.

    CONCLUSION: In patients with chronic CAD and/or PAD, extended combination treatment for a median of 1 year and a maximum of 3 years was associated with incidence rates for efficacy and bleeding that were similar to or lower than those seen during the randomized treatment phase, without any new safety signals.

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