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Phenyl glycosides from Bacopa monnieri with their antioxidant and anti-inflammatory activities. Nat Prod Res 2023:1-6. [PMID: 37732634 DOI: 10.1080/14786419.2023.2258544] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Accepted: 09/08/2023] [Indexed: 09/22/2023]
Abstract
Bacopa monnieri (L.) Wettst (Plantaginaceae), is traditionally used in many countries as neural tonic and memory enhancer, or to relieve acute pain and inflammation. This study described the isolation and identification of one new, bacomoside D3 (1), and seven known phenyl glycosides (2 - 8). The structures of isolates were established by analysis of their spectroscopic data or hydrolysis followed by HPLC analysis together with a comparison to those reported in the literature. These compounds were evaluated for antioxidant and anti-inflammatory activities. Among them, compounds 4 and 5 exhibited strong DPPH radical scavenging activity with IC50 values of 9.77 ± 0.08 and 3.50 ± 0.04 µM, respectively. Compounds 2 and 5 significantly inhibited TNF-α production in LPS-stimulated RAW264.7 cells with IC50 values of 40.60 ± 3.05 and 38.19 ± 1.75 µM, respectively. Furthermore, the active compounds could be efficient inhibitors of oxidants by interfering with the DPPH activity in silico study.
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2
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Dammarane triterpenes and phytosterols from Dysoxylum tpongense Pierre and their anti-inflammatory activity against liver X receptors and NF-κB activation. Steroids 2021; 175:108902. [PMID: 34520797 DOI: 10.1016/j.steroids.2021.108902] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 07/21/2021] [Accepted: 08/11/2021] [Indexed: 11/15/2022]
Abstract
Dysoxylum tpongense Pierre (local name 'Huynh Dan Bap') belonging to family Meliaceae, is a tree (3-10 m height), distributed in the mountainous areas (ca. 1000 m a.s.l.) in North Vietnam. From the dichloromethane fraction of the methanol extract of the leaves and stems of this plant, six dammarane triterpenes, one furanoid diterpene together with three sterols were isolated. Evaluation of biological activities of isolated compounds showed that cabraleahydroxylactone (5), cabraleahydroxylactone 3-acetate (6), and stigmast-4-en-3-one (10) possessed an anti-inflammatory effect against Liver X receptor (LXR) activation in HepG2 cell line model with IC50 values of 20.29 ± 3.69, 24.32 ± 2.99, and 7.09 ± 0.97 (μM), respectively. While three other triterpenoid compounds aglinin C 3- acetate (1), aglinin C (2), and 24-epi-cabraleadiol (4) presented the most significant inhibitory effect against TNF-α induced NF-κB activation in HepG2 cell line in a dose-dependent manner with IC50 values of 12.45 ± 2.37, 23.32 ± 3.25, and 13.95 ± 1.57 μM, respectively. As stigmast-4-en-3-one (10), with structure closely similar to cholesterol, acted selectively on LXRs but not on NF-kB activation pathway, this suggests that stigmast-4-en-3-one (10) can be potentially applied as an agonist on LXR signaling pathway. Pathways LXRs-NF-κB-iNOS expression have a close relationship and play a crucial role in proceeding metabolic abnormalities like atherosclerosis, obesity, inflammation, etc. Thus, the findings showed that dammarane-type triterpenoids from D. tpongense are worthy of further investigation for potential LXR agonists and potent anti-atherogenic agents against atherosclerotic lesion progression.
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Abstract
A new diterpene (1) along with eight known compounds (2-9) were isolated from Excoecaria agallocha leaves. The structure and relative configuration of new compound were established on the basis of spectroscopic data analysis and confirmed by NMR chemical shifts calculation with DP4+ probability. Cytotoxicity of the isolated compounds were also evaluated.
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4
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Phytochemical and pharmacological properties of Myristica fragrans Houtt.: an updated review. Arch Pharm Res 2020; 43:1067-1092. [DOI: 10.1007/s12272-020-01285-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Accepted: 11/04/2020] [Indexed: 01/01/2023]
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Inhibition of PTP1B by farnesylated 2-arylbenzofurans isolated from Morus alba root bark: unraveling the mechanism of inhibition based on in vitro and in silico studies. Arch Pharm Res 2020; 43:961-975. [PMID: 32978714 PMCID: PMC7518952 DOI: 10.1007/s12272-020-01269-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Accepted: 09/22/2020] [Indexed: 12/24/2022]
Abstract
Among the 2-arylbenzofuran derivatives isolated from Morus alba, the farnesylated 2-arylbenzofuran is a rarer constituent. The derivative has been reported to exert anti-obesity effect; however, its inhibitory effect on protein tyrosine phosphatase 1B (PTP1B) has not been investigated. In the previous study, the presence of the farnesyl group in the structure of 2-arylbenzofurans was found to have positive influences on their pancreatic lipase inhibitory activity. In the present study, we have confirmed the authenticity of the notation based on the PTP1B inhibitory activity of farnesylated 2-arylbenzofurans. Specifically, two farnesylated 2-arylbenzofurans [morusalfurans B (2) and C (3)] showed strong inhibitory effects on PTP1B with IC50 values of 8.92 and 7.26 µM, respectively, which was significantly higher than that of the positive controls [sodium orthovanadate (IC50 = 15.10 µM) and ursolic acid (IC50 = 11.34 µM)]. Besides, two 2-arylbenzofurans [morusalfurans A (1) and F (6)], one flavonoid [morusalnol B (9)], and one geranylated stilbene [morusibene A (11)] exhibited PTP1B inhibition with IC50 values ranging from 11.02 to 26.56 µM. Kinetic studies revealed compounds 2, 3, 6, and 11 as mixed type PTP1B inhibitors, while 1 and 9 are known as noncompetitive. Molecular docking simulations demonstrated that these active compounds can bind with the respective catalytic or/and allosteric sites of PTP1B with negative binding energies and the results are in accordance with that of the kinetic studies. To the best of our knowledge, this is the first time, the PTP1B inhibitory activity of eleven compounds (1–11), as well as the mechanism of action underlying the effects on PTP1B enzyme of the active compounds, were investigated. In vitro and in silico results suggest that the farnesylated 2-arylbenzofurans from M. alba may potentially be utilized as an effective treatment therapy for type 2 diabetes mellitus and its associated complications.
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In Vitro Effects of the Acylated StreptokinasePlasminogen Activator Complex BRL 33 575 Incubated with Normal Human Plasma. Thromb Haemost 2018. [DOI: 10.1055/s-0038-1661112] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
SummaryThrombolysis with acylated streptokinase-plasminogen complexes is aimed to achieve fibrinolysis without systemic fibrinogenolysis. The p-aminobenzoyl-streptokinase-(Lys)-plasminogen-complex (BRL 33 575) should be particularly useful due to its slow deacylation rate. Unexpectedly, repeated doses of 10 mg of BRL 33 575 (corresponding to 310'000 streptokinase equivalent units) induced systemic effects in patients though less than streptokinase alone. In vitro incubation of normal human plasma with BRL 33 575 at concentrations used in patients resulted in nearly complete consumption of α2-antiplasmin and plasminogen and significant fibrinogenolysis within 3 hr. This demonstrates that - despite of slow deacylation of BRL 33 575 - the small amounts of activator generated are highly efficacious in activating plasma plasminogen under conditions in which no physiological clearance of the free activator takes place. Simulating the calculated activator release from BRL 33 575 by infusing equivalent amounts of streptokinase into plasma resulted in less pronounced effects. This is probably explained by anti-streptokinase antibodies which will neutralize the initially infused streptokinase but will be bound by BRL 33 575.Our in vitro experiments indicate that further clinical studies should be done with lower doses of BRL 33 575 or prolonged dosage intervals.
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Fifteen Coagulation and Fibrinolysis Parameters in Diabetes Mellitus and in Patients with Vasculopathy. Thromb Haemost 2018. [DOI: 10.1055/s-0038-1661158] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
SummaryFifteen haemostasis parameters have been measured in 48 normal persons, 36 diabetics without and 44 with complications and 27 with peripheral arterial disease. Since the patients groups are older than normals, part of the differences are due to age. However, the differences are significant between normals and patients. They become highly significant for the diabetics with complications and nephropathy (Table 7). In diabetics without complications factor VIII functions, fibrinogen and thrombin time are related to age whereas there is a negative correlation for the fibrinolytic activity and antithrombin III. The diabetic complications shade off the correlations, which subsist only for VIIIR: CoF, VIIIR: Ag, ATIII and lysis before stasis. With Hbalc as dependent variable VIIIR:CoF is the only significant predictor variable in diabetics (Table 9).
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Dissociation of Factor VIII Procoagulant Antigen VIII : CAg and Factor VIII Related Antigen VIIIR : Ag by EDTA - Influence of Divalent Cation on the Binding of VIII: CAg and VIIIR :Ag. Thromb Haemost 2018. [DOI: 10.1055/s-0038-1665252] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
SummaryAssuming 1 U/ml in titrated plasma, the VIII: CAg concentration was found 1.66 U/ml in EDTA-plasma, 1.09 U/ml in heparinized plasma and 0.67 U/ml in serum. Addition of 10 mmol/1 EDTA to titrated and heparinized plasmas increased VIII: CAg 1.5fold. There was no increase of VIII: CAg in serum. Gel filtration of plasmas on different anticoagulants showed an elution of VIII: CAg in the void volume Vo and in the later fractions. The VIII: CAg amount detected in the internal volume increased following the series heparin < citrate < EDTA. Serum VIII: CAg was eluted at 2.2 Vo. Presence of EDTA in the elution buffer or incubation of plasma with EDTA prior to chromatography caused a displacement of practically all VIII: CAg amount in the internal volume with a peak at 2.2-2.3 Vo. VIIIR: Ag was exclusively detected in the void volume.Removal of divalent cation by chelation likely exposes more antigenic determinants of VIII: CAg, which are otherwise masked by steric hindrance due to VIIIR: Ag in citrated and heparinized milieu. Moreover gel filtration of plasma in the presence of EDTA completely dissociates VIII: CAg from VIIIR :Ag. The VIII: CAg fragment, having an estimated molecular weight of 70,000, might also be present in serum.
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Purification and Partial Characterization of a Hereditary Abnormal Antithrombin III Fraction of a Patient with Recurrent Thrombophlebitis. Thromb Haemost 2018. [DOI: 10.1055/s-0038-1650090] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
SummaryA relatively low heparin cofactor activity (0.60 U/ml) was observed in a patient with recurrent superficial thrombophlebitis of the left leg. However, the antigen concentration was in the normal range (1.04 U/ml) and the progressive antithrombin activity was normal. The crossed immunoelectrophoresis in presence of heparin in agarose gel separated the patient's AT-III antigen in 2 fractions with different mobilities. The patient's AT-III was purified for further characterization. The last step of the purification procedure, a heparin-agarose chromatography, led to a separation and a purification of 2 AT-III fractions with different heparin affinities: an abnormal AT-III with reduced heparin affinity and a normal AT-III with a heparin affinity similar to that of AT-III isolated from normal plasmas. Abnormal and normal AT-III share several identical properties as molecular weight, ability to form complexes with thrombin and progressive antithrombin activity.
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Reactivity of a Hereditary Abnormal Antithrombin III Fraction in the Inhibition of Thrombin and Factor Xa. Thromb Haemost 2018. [DOI: 10.1055/s-0038-1650091] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
SummaryTwo different AT-III fractions were purified from the plasma of a patient with recurrent superficial thrombophlebitis. The abnormal AT-III fraction (A-AT) was compared to the normal AT-III fraction (N-AT) in the inhibition of thrombin and factor Xa. Without heparin, both inactivate proteases in a similar manner and at the same rate. However, at low heparin concentration the thrombin inhibition proceeds more slowly with A-AT than with N-AT. At high heparin concentration the difference between A-AT and N-AT becomes very small. The inhibition of factor Xa follows a similar pattern. It is suggested that the heparin binding site of A-AT differs from that of N-AT resulting in a decreased heparin cofactor activity.
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Abstract
SummaryThe procoagulant activity VIII:C was separated from factor VIII antigen (VIIIR:Ag) by gel filtration in the presence of 0.25 mol/l calcium chloride. Antibodies (anti-VIII:C) were obtained by immunization of rabbits with VIII:C. The last step of the purification procedure of antibodies consists of an adsorption on VIIIR:Ag-Sepharose 2 BCL as immunoadsorbent to remove contaminating traces of antibodies against VIIIR:Ag. The anti- VIII:C titer remains unchanged during this adsorption (29 Bethesda units per mg). In solution, anti-VIII:C neutralies factor VIII activity (in plasma, cryoprecipitate or in purified form) and the fragment VIII:C without reacting with VIIIR:Ag. Once immobilized on a solid matrix, i.e.2% agarose, it loses over 95% of its inhibitory capacity. The immobilized anti-VIIIR:Ag binds stoichiometrically the antigen and the activity of plasma factor VIII. These results together suggest that factor VIII is composed of 2 different entities, but undissociated under physiological conditions. Immunophysical analyses as a function of pH and temperature of anti-VIII:C and its complex with factor VIII show properties similar to those of homologous antibodies. The antigen determinants of VIII:C (VIII:CAg) are destroyed at low pHs or high temperatures, and VIII:C can no more form a complex with anti-VIII:C. Purified anti-VIII:C is also used in a two-stage assay to detect VIII:CAg or cross-reacting material in some severe haemophiliacs.
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Abstract
Worldwide, pneumonia is the leading cause of death in infants and young children (aged <5 years). We provide an overview of the global pneumonia disease burden, as well as the aetiology and management practices in different parts of the world, with a specific focus on the WHO Western Pacific Region. In 2011, the Western Pacific region had an estimated 0.11 pneumonia episodes per child-year with 61,900 pneumonia-related deaths in children less than 5 years of age. The majority (>75%) of pneumonia deaths occurred in six countries; Cambodia, China, Laos, Papua New Guinea, the Philippines and Viet Nam. Historically Streptococcus pneumoniae and Haemophilus influenzae were the commonest causes of severe pneumonia and pneumonia-related deaths in young children, but this is changing with the introduction of highly effective conjugate vaccines and socio-economic development. The relative contribution of viruses and atypical bacteria appear to be increasing and traditional case management approaches may require revision to accommodate increased uptake of conjugated vaccines in the Western Pacific region. Careful consideration should be given to risk reduction strategies, enhanced vaccination coverage, improved management of hypoxaemia and antibiotic stewardship.
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MESH Headings
- Anti-Bacterial Agents/therapeutic use
- Asia, Southeastern/epidemiology
- Child
- Child, Preschool
- Asia, Eastern/epidemiology
- Global Health
- Haemophilus Infections/drug therapy
- Haemophilus Infections/epidemiology
- Haemophilus Infections/mortality
- Haemophilus Infections/prevention & control
- Haemophilus Vaccines/therapeutic use
- Haemophilus influenzae
- Humans
- Hypoxia/therapy
- Infant
- Influenza Vaccines/therapeutic use
- Influenza, Human/epidemiology
- Influenza, Human/mortality
- Influenza, Human/prevention & control
- Influenza, Human/therapy
- Pneumococcal Vaccines/therapeutic use
- Pneumonia/drug therapy
- Pneumonia/epidemiology
- Pneumonia/mortality
- Pneumonia/prevention & control
- Pneumonia, Mycoplasma/drug therapy
- Pneumonia, Mycoplasma/epidemiology
- Pneumonia, Mycoplasma/mortality
- Pneumonia, Pneumococcal/drug therapy
- Pneumonia, Pneumococcal/epidemiology
- Pneumonia, Pneumococcal/mortality
- Pneumonia, Pneumococcal/prevention & control
- Respiratory Syncytial Virus Infections/epidemiology
- Respiratory Syncytial Virus Infections/mortality
- Respiratory Syncytial Virus Infections/therapy
- Streptococcus pneumoniae
- Tuberculosis, Pulmonary/drug therapy
- Tuberculosis, Pulmonary/epidemiology
- Tuberculosis, Pulmonary/mortality
- World Health Organization
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Abstract
SUMMARY There are many ways to measure thoracic kyphosis ranging from simple clinical to more complex assessments. We evaluated the correlation among four commonly used kyphosis measures: Cobb angle, Debrunner kyphometer, kyphotic index, and the blocks method. Each measure was correlated with the others, confirming high clinical and research applicability. INTRODUCTION The purpose of this study was to assess the associations among four commonly used measures of thoracic kyphosis in older adults. METHODS Seventy two men and women aged 65-96 were recruited from the San Diego community. Four kyphosis measures were assessed in the same person during a baseline clinic visit. Two measures were done in the lying (L) and two in the standing (ST) position: (1) Cobb angle calculated from dual X-Ray absorptiometry (DXA) images (L), (2) Debrunner kyphometer (DK) angle measured by a protractor (ST), (3) kyphotic index (KI) calculated using an architect's flexicurve ruler (ST), and (4) the blocks method involving counting the number of 1.7 cm-thick blocks required to achieve a neutral head position while lying flat on the DXA table (L). Spearman rank correlation coefficients were used to determine the strength of the association between each kyphosis measure. RESULTS Using the Cobb angle as the gold standard, the blocks method demonstrated the lowest correlation (r(s) = 0.63, p < 0.0001), the Debrunner method had a moderate correlation (r(s) = 0.65, p < 0.0001), and the kyphotic index had the highest correlation (r(s) = 0.68, p < 0.0001). The correlation was strongest between the kyphotic index and the Debrunner kyphometer (r(s) = 0.76, p < 0.0001). CONCLUSION In older men and women, all four measures of thoracic kyphosis were significantly correlated with each other, whether assessed in the lying or standing position. Thus, any of these measures demonstrate both potential clinical and research utility.
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Abstract
INTRODUCTION Influenza B viruses circulate throughout Viet Nam, and their activities vary by region. There have been two antigenically distinct lineages of influenza B viruses co-circulating in the past 20 years; however, only one lineage is selected as a component of contemporary trivalent seasonal influenza vaccines. To improve the understanding of circulating influenza B lineages and influenza vaccine mismatches, we report the virus lineages circulating in northern Viet Nam over an eight-year period (2007-2014). METHODS Lineages of 331 influenza B viruses were characterized by haemagglutination inhibition assay against standard reference ferret (Yamagata) and sheep (Victoria) antisera. Sequence analysis of the haemagglutinin gene was performed in 64 selected influenza B isolates. RESULTS The proportion of influenza B lineages changed by year. The Yamagata lineage predominated in 2007, 2008 and 2012; the Victoria lineage predominated in 2009-2014 except 2012. The two lineages showed continuous evolution over time. The Northern Hemisphere's influenza vaccine components were mismatched with the predominant circulating viruses in 2007, 2009 and 2014. DISCUSSION The seasonality of influenza B activity is more variable in tropical and subtropical regions than in temperate zones. Our data showed a common co-circulation of both influenza B lineages in northern Viet Nam, and it was difficult to predict which one was the predominant lineage. Quadrivalent influenza vaccines containing both lineages may improve the effectiveness of influenza vaccine programmes in the future.
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Allogeneic hematopoietic stem cell transplantation for poor-risk CLL: dissecting immune-modulating strategies for disease eradication and treatment of relapse. Bone Marrow Transplant 2015; 50:1279-85. [DOI: 10.1038/bmt.2015.150] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2015] [Revised: 05/21/2015] [Accepted: 05/22/2015] [Indexed: 12/21/2022]
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Rapid rule out of myocardial infarction with the use of copeptin as a biomarker for cardiac injury. Intern Med J 2015; 44:921-4. [PMID: 25201424 DOI: 10.1111/imj.12526] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2014] [Accepted: 05/05/2014] [Indexed: 12/17/2022]
Abstract
Copeptin is a non-specific marker of an endogenous stress response. A dual biomarker marker approach involving the simultaneous use of troponin and copeptin assays may assist early exclusion of acute coronary syndrome in Australian emergency departments. The utility and limitations of this approach are discussed.
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Abstract
Hopea odorata Roxb. is widely distributed in lowland forests in Vietnam and native to South-East Asia. Due to over-exploitation and habitat destruction, this species are now threatened and mainly restricted to protected areas for survival. In total, 70 adult individuals of three populations include BGM, TP and BE of Hopea odorata were investigated base on nine microsatellite loci. Analysis of molecular variance showed most genetic variation (73%) was within individuals. The mean values of genetic differentiation among populations was high with FST = 0.251. Allelic richness ranged from 2.444 - 3.293, pair wise differentiation was significant. Bayesian cluster analysis and FST values suggest three populations of Hopea odorata could be divided into two groups. Individual trees from the BGM and TP populations were more closely related than those of the BE population. Inbreeding within population was not significant, no null allele evidence was found but evidence for recent bottleneck events were found for the BE population at TPM = 0.01 suggesting that A reduction in the number of individuals could be the result of overharvesting in the past. This research provides additional useful information for conservation, management, and restoration of populations to the Protection Forestry Department, Vietnam.
Sao Đen là loài cây gỗ phân bố rộng rãi trong các khu rừng đất thấp ở Việt Nam và các nước Đông Nam Á. Do khai thác quá mức và môi trường sống bị phá hủy mà loài này đang đứng trước nguy cơ bị đe dọa và hiện chỉ còn phân bố giới hạn trong các khu bảo tồn. Chúng tôi đã tiến hành phân tích đa dạng di truyền của ba quần thể loài Sao đen gồm BGM, TP và BE từ 70 mẫu cây trưởng thành dựa trên chín locus microsatellite. Kết quả phân tích cho thấy sự đa dạng di truyền xảy ra chủ yếu trong các cá thể (73%). Giá trị sai khác di truyền giữa các quần thể là khá cao (FST = 0.251), hệ số đa dạng alen dao dộng từ 2.444 đến 3.293, sự sai khác di truyền giữa các quần thể là có ý nghĩa. Kết quả phân tích cấu trúc di truyền và sự sai khác di truyền giữa ba quần thể đều khá cao. Hiện tượng tự thụ phấn xảy ra trong ba quần thể nghiên cứu chưa có ý nghĩa, không có các bằng chứng về sự xuất hiện của các alen vô nghĩa (điều mà thường xảy ra khi sử dụng chung locus microsatellite cho các loài hoặc các chi có mối quan hệ gần gũi). Nguyên lý thắt cổ chai trong di truyền (bottleneck) có khả năng xảy ra ở quần thể BE cho thấy khả năng trước đây nơi đây đã xảy ra sự khai thác quá mức làm số lượng cá thể giảm đột ngột. Nghiên cứu này cung cấp những thông tin về di truyền quan trọng cho cục Kiểm Lâm trong việc bảo tồn, phục hổi và quản lý bền vững quần thể loài Sao Đen ở Việt Nam.
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The impact of allogeneic stem cell transplantation on the natural course of poor-risk chronic lymphocytic leukemia as defined by the EBMT consensus criteria: a retrospective donor versus no donor comparison. Ann Oncol 2014; 25:200-6. [PMID: 24356631 DOI: 10.1093/annonc/mdt511] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND In a single-center retrospective donor versus no-donor comparison, we investigated if allogeneic stem cell transplantation (alloSCT) can improve the dismal course of poor-risk chronic lymphocytic leukemia (CLL). PATIENTS AND METHODS All patients with CLL who were referred for evaluation of alloSCT within a 7-year time frame and had a donor search indication according to the EBMT criteria or because of Richter's transformation were included. Patients for whom a matched donor could be found within 3 months (matches) were compared with patients without such a donor (controls). Primary end point was overall survival measured from the 3-month landmark after search initiation. RESULTS Of 105 patients with donor search, 97 (matches 83; controls 14) were assessable at the 3-month landmark. Matches and controls were comparable for age, gender, time from diagnosis, number of previous regimens, and remission status. Disregarding if alloSCT was actually carried out or not, survival from the 3-month landmark was significantly better in matches versus controls [hazard ratio 0.38, 95% confidence interval (CI) 0.17-0.85; P = 0.014]. The survival benefit of matches remained significant on multivariate analysis. CONCLUSION This study provides first comparative evidence that alloSCT may have the potential to improve the natural course of poor-risk CLL as defined by the EBMT criteria.
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Metabolic syndrome-related hepatocellular carcinoma treated by volumetric modulated arc therapy. ACTA ACUST UNITED AC 2014; 21:e340-4. [PMID: 24764717 DOI: 10.3747/co.21.1756] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Hepatocellular carcinoma (hcc) is a leading cause of cancer mortality, and its incidence is increasing in developed countries. Risk factors include cirrhosis from viral hepatitis or alcohol abuse. Metabolic syndrome is a newly recognized, but important, risk factor that is likely contributing to the increased incidence of hcc. Surgery is the therapy of choice for hcc, but local therapies are often contraindicated, usually because of advanced disease or comorbid conditions such as cardiac disease (which is associated with metabolic syndrome). Current radiation therapy techniques such as stereotactic body radiotherapy allow for treatment plans that highly conform to the target and provide excellent sparing of normal structures. Radiation therapy is emerging as a viable option in patients not eligible for surgery or other locoregional therapies. Here, we report a case of a large hcc presenting in a patient with metabolic syndrome without significant alcohol history or biochemical liver dysfunction. The patient was not a candidate for locoregional therapies because of cardiac and renal comorbidities typical of patients experiencing the long-term sequelae of metabolic syndrome. Treatment using an arc-based volumetric-modulated arc therapy technique allowed for the highest dose of radiation to be delivered to the tumour while the peripheral radiation dose was minimized. A complete local response was confirmed by computed tomography imaging 21 months after treatment completion.
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Characterization of mannose-binding lectin (MBL) variants by allele-specific sequencing of MBL2 and determination of serum MBL protein levels. ACTA ACUST UNITED AC 2013; 82:410-5. [PMID: 24134411 DOI: 10.1111/tan.12232] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2013] [Revised: 09/21/2013] [Accepted: 09/26/2013] [Indexed: 11/29/2022]
Abstract
Mannose-binding lectin (MBL) is a major component of the lectin pathway of complement activation. High and low MBL levels have been associated with susceptibility and severity of a variety of infectious and autoimmune diseases. Several single-nucleotide polymorphisms (SNPs) in the promoter region and exon 1 of the MBL2 gene are responsible for variations in serum MBL levels. We developed a sequence-based typing method for allele-specific MBL2 genotyping and measured serum MBL protein levels in 24 German blood donors. We identified the common MBL2 haplotypes including five promoter polymorphisms in linkage with the Q allele and correlated serum MBL levels with the respective genotypes. The genotyping method presented here could provide a basis for confirmatory studies in larger cohorts.
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No impact of KIR-ligand mismatch on allograft outcome in HLA-compatible kidney transplantation. Am J Transplant 2013; 13:1063-1068. [PMID: 23398855 DOI: 10.1111/ajt.12134] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2012] [Revised: 11/15/2012] [Accepted: 12/04/2012] [Indexed: 01/25/2023]
Abstract
Natural killer (NK) cell function can be modulated by the killer cell immunoglobulin-like receptors (KIR) which interact with human leukocyte antigen (HLA) class I molecules on target cells. KIR-ligand mismatching has recently been shown by van Bergen et al. (American Journal of Transplantation 2011; 11(9): 1959-1964) to be a significant risk factor for long-term graft loss in HLA-A, -B and -DR compatible kidney transplants. To verify this potentially important finding, we performed genotyping of 608 deceased-donor kidney graft recipients and their HLA-A, -B and -DR compatible donors for KIR and HLA, using samples and clinical data provided by the Collaborative Transplant Study. Graft survival of KIR-ligand-matched and -mismatched transplants was compared. We found no impact of KIR-ligand mismatching on 10-year graft survival in HLA-A, -B, -DR compatible kidney transplants. Further analysis did not reveal a significant effect of recipient activating/inhibitory KIR or KIR genotypes on graft survival. Our data do not support the concept that KIR-HLA matching might serve as a tool to improve long-term renal allograft survival.
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P1-06-24: Nuclear Localization of Stat5a Predicts Response to Antiestrogen Therapy and Prognosis of Clinical Breast Cancer Outcome. Cancer Res 2011. [DOI: 10.1158/0008-5472.sabcs11-p1-06-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Nuclear-localized and tyrosine-phosphorylated Stat5 has been reported as a favorable prognostic marker and predictor of response to antiestrogen therapy in breast cancer. Phospho-Stat5 antibodies do not distinguish between phosphorylated Stat5a and the closely related Stat5b, but Stat5a is considered more critical for normal mammary development than Stat5b. The purpose of this study was to determine whether levels of nuclear-localized Stat5a protein (Nuc-Stat5a) were prognostic of clinical outcome or predictive of antiestrogen response. Stat5a was detected by traditional diaminobenzidine-chromogen immunohistochemistry (IHC) and pathologist scoring or by quantitative immunofluorescence in five archival cohorts of breast cancer. Levels of nuclear-localized Stat5a (Nuc-Stat5a) were evaluated by pathologist scoring of whole tissue sections detected by IHC or automated quantitative analysis (AQUA) of immunofluorescently-labeled tissue microarrays. Levels of Nuc-Stat5a were reduced in invasive breast cancer tissues and lymph node metastases compared to normal tissue and ductal carcinoma in situ when quantified by AQUA (Material I; n=180). Tissues from patients not treated with adjuvant therapy or treated with antiestrogen monotherapy were analyzed according to Nuc-Stat5a status for breast cancer-specific survival (CSS) and time to recurrence (TTR) using univariate and multivariate statistical models, adjusting for clinical features including tumor grade, size, lymph node and ER, PR and Her2 status. In two prognostic cohorts of node-negative breast cancer patients, low expression of Nuc-Stat5a, detected by standard IHC (Material II; n=223) or quantitative analysis (Material III; n=198), was prognostic of poor breast cancer outcome as measured by univariate and multivariate CSS (Material II/III) and TTR (Material II). CSS and TTR analysis of two independent materials of tumors from patients treated with antiestrogen monotherapy and analyzed by standard IHC (Material IV; n=73) or quantitative immunofluorescence (Material V; n=97) indicated that patients whose tumors expressed low levels of Nuc-Stat5a were at a greater than 4-fold risk of antiestrogen therapy failure when adjusted for hormone receptor status and clinical features (multivariate CSS: Material IV HR=4.3 (1.2,15.6), p=0.03; Material V HR=5.0 (1.87,13.06), p=0.001). In conclusion, loss of Nuc-Stat5a is a promising independent marker of poor breast cancer prognosis in node-negative, non-adjuvant treated breast cancer patients. Additionally, Nuc-Stat5a may be a useful clinical tool to predict tumor response to antiestrogen therapy.
Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P1-06-24.
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Abstract
HLA-C is the major inhibitory ligand for killer immunoglobulin-like receptors (KIRs) that are expressed on natural killer (NK) cells. Based on their KIR specificity, HLA-C alleles can be divided into two groups, termed HLA-C1 and HLA-C2. Donor HLA-C group has recently been identified by Hanvesakul et al. (Am J Transplant 2008) as a critical determinant of clinical outcome following liver transplantation: Possession of at least one HLA-C group 2 allele by the donor was associated with significantly improved long-term graft and patient survival, presumably due to an inhibition of host NK cell function. To verify this study, we performed genotyping of 913 deceased liver donors for the relevant KIR epitopes of HLA-C and correlated the presence or absence of donor HLA-C2 genotype with graft and patient survival. In our study, donor HLA-C2 genotype had no impact on 10-year graft or patient survival. We cannot confirm a major role of donor HLA-C2 genotype on long-term allograft survival after liver transplantation.
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Identification of two novel HLA alleles, HLA-A*02010103 and HLA-B*4455, and characterization of the complete genomic sequence of HLA-A*290201. ACTA ACUST UNITED AC 2008; 72:397-400. [PMID: 18647362 DOI: 10.1111/j.1399-0039.2008.01100.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We describe two novel human leukocyte antigen (HLA) alleles, HLA-A*02010103 and HLA-B*4455, that were discovered in two unrelated Caucasian individuals. In addition, we report the full-length genomic sequence of HLA-A*290201. Compared with HLA-A*02010101, HLA-A*02010103 has three nucleotide (nt) changes within intron 1, which is altered to a sequence typical of the HLA-A*23/A*24 allele group. In HLA-B*4455, an nt exchange occurred in codon 9 of HLA-B*44020101, resulting in a change of the amino acid coding from tyrosine to histidine. We sequenced HLA-A*290201 from nt -108 to nt 2922, encompassing all exons and introns as well as parts of the 5' and 3' untranslated regions. Previously, the full-length genomic sequence was known only for HLA-A*29010101, which is found at a lower frequency in Caucasians than HLA-A*290201.
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Identification and characterization of three novel HLA alleles, HLA-A*240214, HLA-A*3215 and HLA-DQB1*060302. ACTA ACUST UNITED AC 2008; 70:511-4. [PMID: 17990990 DOI: 10.1111/j.1399-0039.2007.00958.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We describe three novel human leukocyte antigen (HLA) alleles found in three different Caucasians, HLA-A*240214, HLA-A*3215 and HLA-DQB1*060302. As compared with HLA-A*24020101, HLA-A*240214 has a synonymous nucleotide (nt) exchange in codon 132. HLA-A*240214 may have arisen from intergenic recombination between HLA-A*24020101 and an HLA-B or HLA-C allele. The second novel allele, HLA-A*3215, has three nucleotide exchanges as compared with HLA-A*320101. These variations result in amino acid exchanges in codons 62 and 63, generating the public epitope of the serological HLA-A10 group. The third novel allele, HLA-DQB1*060302, has one synonymous nucleotide exchange within codon 38 as compared with HLA-DQB1*060301. In a family segregation study, we found that HLA-DQB1*060302, similar to the known HLA-DQB1*060301 allele, cosegregates with HLA-DRB1*1301.
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Abstract
In hematopoietic stem cell transplantation (HSCT), disparities between recipients and donors for minor histocompatibility antigens (mHags) have been shown to be related to graft-versus-host disease (GVHD) and graft-versus-leukemia (GVL) effects. We investigated the effect of mHag mismatches on kidney allograft survival. Out of 33 785 kidney transplants on which DNA and clinical data were available to the Collaborative Transplant Study (CTS), 702 recipient/donor pairs could be identified as HLA-A, -B and -DRB1 matched first transplants of Caucasian origin. These pairs were typed for genetic polymorphisms of the mHags HA-1, HA-2, HA-3, HA-8, HB-1, ACC-1 and UGT2B17. Because mHags are presented in an HLA-restricted manner, only HLA-A*02 positive pairs were included in the analysis of HA-1, HA-2 and HA-8. Similarly, only HLA-A*01, HLA-B*44 and HLA-A*24 positive pairs were considered for the evaluation of HA-3, HB-1 and ACC-1, respectively, whereas UGT2B17 compatible transplants were assessed in HLA-A*29 and HLA-B*44 positive pairs. None of the mHag disparities showed a statistically significant effect on death-censored 5-year graft survival. This report represents the first large-scale study on the relevance of mHags in kidney transplantation.
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Characterization of a new HLA-B allele, HLA-B*5312, and re-evaluation of the published sequences of the untranslated regions of HLA-B*35 and HLA-B*53. ACTA ACUST UNITED AC 2007; 70:319-23. [PMID: 17767554 DOI: 10.1111/j.1399-0039.2007.00900.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We report a novel human leukocyte antigen (HLA)-B allele, HLA-B*5312. Compared with HLA-B*530101, there is one silent substitution at nucleotide 438 and two non-synonymous substitutions at nucleotides 431 and 440, causing a change of the amino acid sequence (Asn-->Ser at codon 77 and Ile-->Thr at codon 80, respectively) within the Bw4 epitope. In contrast to the published sequences (IMGT/HLA Database, version 2.16.0, January 2007), we found that HLA-B*530101 had a C instead of a T at nucleotide -221, whereas HLA-B*350101 had a C instead of an A at nucleotide 2992. According to our sequencing results, HLA-B*5312 resembles HLA-B*350101 regarding its sequence of the untranslated regions. HLA-B*5312 may have been the result of a double crossing over event during which HLA-B*350101 adopted a Bw4 motif.
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Sonic Hedgehog regulates Hes1 through a novel mechanism that is independent of canonical Notch pathway signalling. Oncogene 2007; 27:1489-500. [PMID: 17873912 DOI: 10.1038/sj.onc.1210767] [Citation(s) in RCA: 126] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Aberrant regulation of signalling mechanisms that normally orchestrate embryonic development, such as the Hedgehog, Wnt and Notch pathways, is a common feature of tumorigenesis. In order to better understand the neoplastic events mediated by Hedgehog signalling, we identified over 200 genes regulated by Sonic Hedgehog in multipotent mesodermal cells. Widespread crosstalk with other developmental signalling pathways is evident, suggesting a complex network of interactions that challenges the often over-simplistic representation of these pathways as simple linear entities. Hes1, a principal effector of the Notch pathway, was found to be a target of Sonic Hedgehog in both C3H/10T1/2 mesodermal and MNS70 neural cells. Desert Hedgehog also elicited a strong Hes1 response. While Smoothened function was found necessary for upregulation of Hes1 in response to Sonic Hedgehog, the mechanism does not require gamma-secretase-mediated cleavage of Notch receptors, and appears to involve transcription factors other than RBP-Jkappa. Thus, we have defined a novel mechanism for Hes1 regulation in stem-like cells that is independent of canonical Notch signalling.
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A new PCR-SSP typing method for six single-nucleotide polymorphisms impairing the blood-clotting cascade as well as T-cell stimulation. ACTA ACUST UNITED AC 2005; 66:650-5. [PMID: 16305681 DOI: 10.1111/j.1399-0039.2005.00493.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Single-nucleotide polymorphisms (SNPs) within the genes of factor V (FV) (G1691A; exon 10), prothrombin (FII) (G20210A; 3'untranslated - region) and methylenetetrahydrofolate reductase (MTHFR) (C677T; exon 4) are associated with hypercoagulability, and systematic screening of individuals being at higher risk of thrombosis has been suggested. SNPs in the 2q33 region within the genes of CD28 (+17T/C; intron 3) and CTLA4 (-318C/T; promoter and +49A/G; exon 1) are likely to affect T-cell proliferation and antigen presentation signaling, which may lead to altered sensitivity of allograft or self-tissue recognition and affect the incidence of autoimmune diseases. We developed primers that allow specific amplification of these six SNPs at test conditions identical with those used for HLA typing with the CTS PCR-SSP reagents. One hundred ninety-six healthy German Caucasian individuals were tested for the six SNPs. The genotype frequencies for all SNPs were in Hardy-Weinberg equilibrium. There was no significant difference in the distribution of genotypes when compared to other published studies in which these SNPs were tested. The described PCR-SSP method can be used to screen large numbers of patients for these SNPs.
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Description and characterization of two new HLA alleles, B*4051 and DRB1*1364, identified by sequence-based typing*. ACTA ACUST UNITED AC 2005; 66:151-5. [PMID: 16029439 DOI: 10.1111/j.1399-0039.2005.00440.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Human leukocyte antigen (HLA)-B and HLA-DRB1 typing in two female individuals revealed reaction patterns that did not correspond to any known HLA-B specificity and appeared to identify a very rare HLA-DRB1 allele, respectively. Sequence-based analysis of these samples revealed two new HLA alleles, one similar to B*4023 and the other to DRB1*1308. The new HLA-B allele, which was assigned the name HLA-B*4051, could have been generated by a double crossing over recombination between B*4001 and B*1401 or 1402, whereas DRB1*1364, the new DRB1 allele, could have been generated either by a double crossing over recombination between DRB1*1308 and DRB1*1201, 1202, or 1203 or by two independent crossing over events between DRB1*1401, DRB1*1201, 1202, or 1203 and DRB1*1301.
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Quantitation of bacteria in bone marrow from patients with typhoid fever: relationship between counts and clinical features. J Clin Microbiol 2001; 39:1571-6. [PMID: 11283089 PMCID: PMC87972 DOI: 10.1128/jcm.39.4.1571-1576.2001] [Citation(s) in RCA: 117] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Enteric fever is the only bacterial infection of humans for which bone marrow examination is routinely recommended. A prospective study of the concentrations of bacteria in the bone marrow and their relationship to clinical features was conducted with 120 Vietnamese patients with suspected enteric fever, of whom 89 had confirmed typhoid fever. Ninety-three percent of the Salmonella enterica serovar Typhi samples isolated were resistant to ampicillin, chloramphenicol, and co-trimoxazole. For 81 patients with uncomplicated typhoid and satisfactory bone marrow aspirates, the number of serovar Typhi CFU in bone marrow aspirates was a median value of 9 (interquartile range [IQR], 1 to 85; range, 0.1 to 1,580) compared to 0.3 (IQR, 0.1 to 10; range, 0.1 to 399) CFU/ml in simultaneously sampled blood. The ratio of individual blood counts to bone marrow counts was 10 (IQR, 2.3 to 97.5). The number of bacteria in blood but not bone marrow was correlated inversely with the duration of preceding fever. Thus, with increasing duration of illness the ratio of bone marrow-to-blood bacterial concentrations increased; the median ratio was 4.8 (IQR, 1 to 27.5) during the first week compared with 158 (IQR, 60 to 397) during the third week. After lysing the host cells, the median ratio of viable bone marrow to blood increased, reflecting the higher concentration of intracellular serovar Typhi in the bone marrow. Effective antibiotic pretreatment had a significantly greater effect in reducing blood counts compared to bone marrow counts (P < 0.001). Thus, bacteria in the bone marrow of typhoid patients are less affected by antibiotic treatment than bacteria in the blood. The numbers of bacteria in bone marrow correlated negatively with the white blood cell (R = -0.3, P = 0.006) and platelet counts (R = -0.32, P = 0.01) and positively with fever clearance time after treatment (R = 0.4, P < 0.001). The bacterial load in bone marrow therefore may reflect the clinical course of the infection, and high levels may suppress neutrophil proliferation.
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Identification of a matrix-degrading phenotype in human tuberculosis in vitro and in vivo. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2001; 166:4223-30. [PMID: 11238675 DOI: 10.4049/jimmunol.166.6.4223] [Citation(s) in RCA: 84] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Tuberculous meningitis is characterized by cerebral tissue destruction. Monocytes, pivotal in immune responses to Mycobacterium tuberculosis, secrete matrix metalloproteinase-9 (MMP-9), which facilitates leukocyte migration across the blood-brain barrier, but may cause cerebral injury. In vitro, human monocytic (THP-1) cells infected by live, virulent M. tuberculosis secreted MMP-9 in a dose-dependent manner. At 24 h, MMP-9 concentrations increased 10-fold to 239 +/- 75 ng/ml (p = 0.001 vs controls). MMP-9 mRNA became detectable at 24--48 h. In contrast, tissue inhibitor of matrix metalloproteinase-1 (TIMP-1) gene expression and secretion were similar to constitutive levels from controls at 24 h and increased just 5-fold by 48 h. In vivo investigation revealed MMP-9 concentration per leukocyte in cerebrospinal fluid (CSF) from tuberculous meningitis patients (n = 23; median (range), 3.19 (0.19--31.00) ng/ml/cell) to be higher than that in bacterial (n = 12; 0.23 (0.01--18.37) ng/ml/cell) or viral meningitis (n = 20; 0.20 (0.04--31.00) ng/ml/cell; p < 0.01). TIMP-1, which was constitutively secreted into CSF, was not elevated in tuberculous compared with bacterial meningitis or controls. Thus, a phenotype in which MMP-9 activity is relatively unrestricted by TIMP-1 developed both in vitro and in vivo. This is functionally significant, since MMP-9 concentrations per CSF leukocyte (but not TIMP-1 concentrations) were elevated in fatal tuberculous meningitis and in patients with signs of cerebral tissue damage (unconsciousness, confusion, or neurological deficit; p < 0.05). However, MMP-9 activity was unrelated to the severity of systemic illness. In summary, M. tuberculosis-infected monocytic cells develop a matrix-degrading phenotype, which was observed in vivo and relates to clinical signs reflecting cerebral injury in tuberculous meningitis.
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MESH Headings
- Adult
- Cell Line
- Enzyme Activation/genetics
- Extracellular Matrix/enzymology
- Extracellular Matrix/microbiology
- Extracellular Matrix/pathology
- Female
- Gene Expression Regulation
- Humans
- Leukocyte Count
- Matrix Metalloproteinase 9/biosynthesis
- Matrix Metalloproteinase 9/genetics
- Matrix Metalloproteinase 9/metabolism
- Meningitis, Bacterial/cerebrospinal fluid
- Meningitis, Bacterial/enzymology
- Meningitis, Bacterial/metabolism
- Meningitis, Bacterial/pathology
- Meningitis, Viral/cerebrospinal fluid
- Meningitis, Viral/enzymology
- Meningitis, Viral/metabolism
- Meningitis, Viral/pathology
- Monocytes/enzymology
- Monocytes/metabolism
- Monocytes/microbiology
- Mycobacterium tuberculosis/pathogenicity
- Phenotype
- Tissue Inhibitor of Metalloproteinase-1/biosynthesis
- Tissue Inhibitor of Metalloproteinase-1/genetics
- Tissue Inhibitor of Metalloproteinase-1/metabolism
- Transcription, Genetic
- Tuberculosis, Meningeal/cerebrospinal fluid
- Tuberculosis, Meningeal/enzymology
- Tuberculosis, Meningeal/microbiology
- Tuberculosis, Meningeal/pathology
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Noninvasive measurement of microvascular leakage in patients with dengue hemorrhagic fever. Clin Infect Dis 2001; 32:243-53. [PMID: 11170914 DOI: 10.1086/318453] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2000] [Revised: 06/12/2000] [Indexed: 11/03/2022] Open
Abstract
Dengue shock syndrome (DSS) is a potentially lethal complication of dengue virus infection associated with hypotension and leakage of plasma water into the extravascular space. To determine whether the underlying pathophysiology of DSS is distinct from that in milder forms of the disease, we assessed microvascular permeability, by use of strain gauge plethysmography, in Vietnamese children with DSS (n=19), or dengue hemorrhagic fever (DHF) without shock (n=16), and in healthy control children (n=15). At admission and after fluid resuscitation, the mean coefficient of microvascular permeability (K(f)) for the patients with dengue was approximately 50% higher than that for the control patients (P=.02). There was no significant difference in K(f) between the 2 groups of patients with dengue; this suggests the same underlying pathophysiology. We hypothesize that in patients with DSS, the fluctuations in K(f) are larger than those in patients with DHF, which leads to short-lived peaks of markedly increased microvascular permeability and consequent hemodynamic shock.
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Risk factors for typhoid fever in the Mekong delta, southern Viet Nam: a case-control study. Trans R Soc Trop Med Hyg 2001; 95:19-23. [PMID: 11280056 DOI: 10.1016/s0035-9203(01)90318-9] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
In order to identify risk factors for typhoid fever in a highly endemic area, we undertook a case-control study in the Mekong delta, Viet Nam. Cases were 144 consecutive patients admitted to hospital with blood culture-confirmed typhoid fever. Two controls (1 in the hospital and 1 in the community) were chosen for each case. Standardized interviews were conducted with questions regarding recent contact with a typhoid fever patient, eating habits, hygiene and socio-economic level. Cases were more likely to have been in contact with a patient with typhoid fever than hospital controls (adjusted odds ratio (OR) = 5.2, 95% confidence interval (95% CI) 1.7-15.9) or community controls (adjusted OR = 11.9, 95% CI 2.3-60.7); 11% and 14% of typhoid fever cases (compared to hospital or community controls, respectively) were attributable to recent contact with a patient with this disease. These findings suggest that strategies directed towards the persons in contact with a patient might reduce the incidence of secondary cases of typhoid fever.
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Abstract
OBJECTIVE We wanted to design an inexpensive, convenient database to store digital radiographic images of multiple formats. CONCLUSION We designed a database that could be saved in a standard format using readily available software. Users of our database can save images in a Joint Photographic Experts Group (JPEG) format, allowing their easy incorporation into other programs.
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An interleukin-2-IgG-Fas ligand fusion protein suppresses delayed-type hypersensitivity in mice by triggering apoptosis in activated T cells as a novel strategy for immunosuppression. Transplantation 2000; 69:1386-91. [PMID: 10798759 DOI: 10.1097/00007890-200004150-00030] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Cell-mediated immune responses can be down-regulated by induction of apoptosis of immunoreactive lymphocytes. In the present study, we have tested the feasibility of a strategy for immunosuppression by the selective induction of apoptosis in activated, interleukin (IL)-2 receptor-positive lymphocytes, using a triple IL-2-IgG-FasL fusion protein. The IL-2-IgG-FasL fusion protein combines IL-2 for the selection of activated T cells, with the extracellular domain of the FasL molecule for inducing T-cell apoptosis. These components were separated by the Fc part of IgG1 serving as a spacer as well as for half-life prolongation. METHODS The gene for the chimeric protein was created by fusing DNA sequences encoding for the three functional components: human IL-2, the Fc part of human IgG1, and the extracellular domain of murine FasL. When the fusion gene was expressed in murine J558L cells, we obtained soluble dimeric immunoglobulin-like proteins in the supernatant. After analyzing the function of the IL-2 and FasL portions individually in vitro, a delayed-type hypersensitivity (DTH) reaction to sheep red blood cells as model for cell-mediated immune responses was investigated to evaluate the IL-2-IgG-FasL-mediated immunosuppression in vivo. RESULTS In vitro, the IL-2-IgG-FasL fusion protein supported IL-2-dependent proliferation of Fas-resistant CTLL-2 cells, whereas concanavalin A-T blasts were induced to undergo apoptosis by the FasL portion. In vivo, this fusion protein potently inhibited a murine DTH. This was associated with an increased rate of apoptosis in activated lymphocytes in the spleen, even at very low doses of the fusion protein. Furthermore, a second antigen challenge 10 days after IL-2-IgG-FasL treatment still failed to elicit a DTH response. CONCLUSION The abrogation of a standard T cell-dependent immune response in vivo demonstrates that IL-2-IgG-FasL can be successfully exploited to trigger the death of deleterious T cells, presenting a potentially useful strategy in the management of autoimmune diseases and allotransplant rejections.
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Unusually low clearance of two CYP3A substrates, alprazolam and trazodone, in a volunteer subject with wild-type CYP3A4 promoter region. J Clin Pharmacol 2000; 40:200-4. [PMID: 10664927 DOI: 10.1177/00912700022008748] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
A healthy 40-year-old Caucasian male volunteer displayed unusually low clearance and long elimination half-life of alprazolam and trazodone, two CYP3A substrate drugs, following single-dose oral administration in clinical pharmacokinetic studies. Genomic DNA isolated from the individual's peripheral blood was subjected to polymerase chain reaction amplification and subsequent sequence analysis of a 592 base-pair segment upstream from the CYP3A coding region. The analysis revealed no variation from wild-type in the nucleotide present at position -290, previously suggested to influence expression and/or activity of CYP3A. The functional significance of this promoter region mutation is unclear and requires further evaluation.
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Regulated and endothelial cell-specific expression of Fas ligand: an in vitro model for a strategy aiming at inhibiting xenograft rejection. Transplantation 1998; 66:1126-31. [PMID: 9825805 DOI: 10.1097/00007890-199811150-00002] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Immunologically privileged sites have been shown to express Fas ligand (FasL) and may protect themselves by inducing apoptosis of infiltrating inflammatory cells. We asked whether the Fas/FasL interaction could be used to protect a xenograft from rejection. We proposed that endothelial cells that are resistant to Fas-mediated killing could be considered as a vehicle for expression of recombinant FasL. METHODS Based on the tetracycline-regulated expression system, constructs were designed that allow endothelial cell-specific and regulated expression of FasL by placing the tetracycline-dependent transactivator under control of the murine intercellular adhesion molecule-2 promoter. RESULTS Primary bovine endothelial cells transfected with FasL efficiently killed Fas-expressing cells in a regulated manner. Not only Fas-positive cell lines but also human peripheral blood lymphocytes underwent apoptosis upon exposure to FasL-transfected endothelial cells. CONCLUSION This in vitro model may provide tools for the generation of transgenic animals to be used as donors for vascularized xenograft transplantation.
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Abstract
In an open-label, randomized trial, 44 Vietnamese children with diphtheria were given penicillin therapy (intramuscular benzylpenicillin, 50,000 U/[kg.d] for 5 days and then oral penicillin, 50 mg/[kg.d] for 5 days), and 42 were given erythromycin therapy (50 mg/[kg.d] orally for 10 days). There were no differences in times to membrane clearance or bacteriologic clearance, but median times to fever clearance were 27 hours (95% confidence interval [CI], 19-30; range, 0-124 hours) for penicillin recipients and 46 hours (95% CI, 34-54; range, 0-148 hours) for erythromycin recipients (P = .0004). In the penicillin group, acute treatment failed for one patient, and one patient relapsed. Three patients in the penicillin group developed diphtheritic myocarditis as evidenced by abnormal electrocardiograms. Erythromycin did not cause prolongation of the QT interval corrected for heart rate. Cultures of specimens from 15 patients (17.4%) were positive for toxigenic Corynebacterium diphtheriae. All isolates were susceptible to penicillin, but for isolates (27%), all of which were from patients who received penicillin treatment, were resistant to erythromycin (minimum inhibitory concentrations, > 64 mg/L). Penicillin is recommended as first-line treatment for diphtheria in Vietnam.
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New susceptibility locus for rheumatoid arthritis suggested by a genome-wide linkage study. Proc Natl Acad Sci U S A 1998; 95:10746-50. [PMID: 9724775 PMCID: PMC27966 DOI: 10.1073/pnas.95.18.10746] [Citation(s) in RCA: 347] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/17/1998] [Indexed: 11/18/2022] Open
Abstract
Rheumatoid arthritis (RA), the most common autoimmune disease, is associated in families with other autoimmune diseases, including insulin-dependent diabetes mellitus (IDDM). Its genetic component has been suggested by familial aggregation (lambdas = 5), twin studies, and segregation analysis. HLA, which is the only susceptibility locus known, has been estimated to account for one-third of this component. The aim of this paper was to identify new RA loci. A genome scan was performed with 114 European Caucasian RA sib pairs from 97 nuclear families. Linkage was significant only for HLA (P < 2.5.10(-5)) and nominal for 19 markers in 14 other regions (P < 0.05). Four of the loci implicated in IDDM potentially overlap with these regions: the putative IDDM6, IDDM9, IDDM13, and DXS998 loci. The first two of these candidate regions, defined in the RA genome scan by the markers D18S68-D18S61-D18S469 (18q22-23) and D3S1267 (3q13), respectively, were studied in 194 additional RA sib pairs from 164 nuclear families. Support for linkage to chromosome 3 only was extended significantly (P = 0.002). The analysis of all 261 families provided a linkage evidence of P = 0. 001 and suggested an interaction between this putative RA locus and HLA. This locus could account for 16% of the genetic component of RA. Candidate genes include those coding for CD80 and CD86, molecules involved in antigen-specific T cell recognition. In conclusion, this first genome scan in RA Caucasian families revealed 14 candidate regions, one of which was supported further by the study of a second set of families.
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The Role of Water in the Intercalation of Kaolinite with Potassium Acetate. J Colloid Interface Sci 1998; 204:227-36. [PMID: 9698400 DOI: 10.1006/jcis.1998.5604] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Water in intercalated kaolinites is observed first as bands inthe hydroxyl-stretching region at 3300 to 3550 cm-1 and bythe water H-O-H bending vibrations in the 1560 to 1680-cm-1 region. For potassium-acetate-intercalated kaolinite, hydroxyl-stretching bands attributed to water are observed at approximately 3540, approximately 3475, approximately 3430, and approximately 3380 cm-1. Water bending modes areobserved at 1560, 1586, 1610, and 1679 cm-1. These bands are attributed to (a) water molecules adsorbed on the kaolinite surface, (b) zeolitic water, (c) molecular first layer water, and (d) orderedwater on the hydroxyl surface, respectively. The intensities ofthe bands are a function of the method of preparation of the intercalated kaolinite. As the kaolinite was washed for varying time intervals, the 1560 cm-1 band decreased in intensity more rapidly than the 1610 cm-1 band. Even after washing for 24 h significant concentrations of water remained on the kaolinite and only heating removed the water. The 1560, 1586, and 1610 cm-1 bands are attributed (a) to free or non-hydrogen-bonded water held in the interlayer spaces of the kaolinite, (b) to water in the hydration sphere of the potassium ion, and (c) to surface-adsorbed water on the kaolinite layers. In kaolinites intercalated under pressure, an additional band was observed at 1679 cm-1. It is proposed that this band is due to water coordinated to the kaolinite surface. Copyright 1998 Academic Press.
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Systemic endothelial activation occurs in both mild and severe malaria. Correlating dermal microvascular endothelial cell phenotype and soluble cell adhesion molecules with disease severity. THE AMERICAN JOURNAL OF PATHOLOGY 1998; 152:1477-87. [PMID: 9626052 PMCID: PMC1858439] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Fatal Plasmodium falciparum malaria is accompanied by systemic endothelial activation. To study endothelial activation directly during malaria and sepsis in vivo, the expression of cell adhesion molecules on dermal microvascular endothelium was examined in skin biopsies and correlated with plasma levels of soluble (circulating) ICAM-1, E-selectin, and VCAM-1 and the cytokine tumor necrosis factor (TNF)-alpha. Skin biopsies were obtained from 61 cases of severe malaria, 42 cases of uncomplicated malaria, 10 cases of severe systemic sepsis, and 17 uninfected controls. Systemic endothelial activation, represented by the up-regulation of inducible cell adhesion molecules (CAMs) on endothelium and increased levels of soluble CAMs (sCAMs), were seen in both severe and uncomplicated malaria and sepsis when compared with uninfected controls. Plasma levels of sICAM-1, sVCAM-1, and sE-selectin correlated positively with the severity of malaria whereas TNF-alpha was raised nonspecifically in malaria and sepsis. Immunohistochemical evidence of endothelial activation in skin biopsies did not correlate with sCAM levels or disease severity. This indicates a background of systemic endothelial activation, which occurs in both mild and severe malaria and sepsis. The levels of sCAMs in malaria are thus not an accurate reflection of endothelial cell expression of CAMs in a particular vascular bed, and other factors must influence their levels during disease.
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Association of rheumatoid arthritis with an amino acid allelic variation of the T cell receptor. ARTHRITIS AND RHEUMATISM 1997; 40:1387-90. [PMID: 9259417 DOI: 10.1002/art.1780400805] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
OBJECTIVE To investigate allelic variations of T cell receptor residues for a contribution to rheumatoid arthritis (RA) susceptibility. METHODS We conducted an RA case-control study involving 1,579 northwest Europeans: 766 patients with erosive and rheumatoid factor-positive disease and 813 control subjects. Productive changes of segments TCRAV6S1, TCRAV7S1, TCRAV8S1, TCRAV10S2, and TCRBV6S1, TCRBV6S7 were investigated by single-strand conformation polymorphisms. The TCRAV8S1 association was confirmed by restriction fragment length polymorphism. RESULTS In the systematic study (77 patients and 119 controls), an increase in 1 TCRAV8S1 genotype was found in the RA patients (P = 0.0004). This finding was replicated in 2 further populations, one from France (212 patients and 254 controls) and the other from Britain (477 patients and 440 controls), with a similar odds ratio (OR), which allowed pooling of the data and confirmation of the association (OR 1.3 [95% confidence interval 1.1-1.7], P = 0.008). CONCLUSION These findings show evidence that TCRA is an RA susceptibility locus.
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Severe and complicated malaria treated with artemisinin, artesunate or artemether in Viet Nam. Trans R Soc Trop Med Hyg 1997; 91:465-7. [PMID: 9373657 DOI: 10.1016/s0035-9203(97)90287-x] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
One hundred and seventy five Vietnamese adults with severe and complicated malaria admitted to a rural district hospital were entered into an open randomized comparative study to compare 4 treatment regimens based on artemisinin and its derivatives. The median time of defervescence was 48 h (95% confident interval [CI] 38-58 h) in those given intramuscular (i.m.) artemether, 42 h (95% CI 36-48 h) in those given artemisinin suppositories, 36 h (95% CI 30-42 h) in those receiving artesunate (i.m.) and 30 h (95% CI 18-42 h) in those receiving intravenous artesunate (P = 0.13). The respective median parasite clearance times were 30 h (95% CI 26-34 h), 30 h (95% CI 24-36 h), 24 h (95% CI 15-33 h), and 24 h (95% CI 15-33 h) (P = 0.30); the median times for recovery of consciousness were 47 h (95% CI 31-63 h), 24 h (95% CI 18-30 h), 30 h (95% CI 18-42 h), and 24 h (95% CI 4-44 h) (P = 0.18); and the mortality rates were 11.1%, 17.6%, 10.2% and 16.6%, respectively (P = 0.64). There was no significant difference in efficacy between the 4 treatments.
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Clearance kinetics of parasites and pigment-containing leukocytes in severe malaria. Blood 1996; 88:4694-700. [PMID: 8977263] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
In tropical areas, where unsupervised use of antimalarial drugs is common, patients with an illness consistent clinically with severe malaria but with negative blood smears pose a management dilemma. Malaria pigment is evident in peripheral blood leukocytes in greater than 90% of patients with severe malaria. To characterize the clearance kinetics of parasitized erythrocytes and malaria pigment-containing leukocytes, sequential peripheral blood and intradermal smears were assessed in 27 adult Vietnamese patients with severe falciparum malaria. The clearance of parasitized erythrocytes and pigment-containing monocytes (PCMs) followed first order kinetics. The elimination of pigment-containing neutrophils (PCNs) was first order initially, but deviated from this when counts were low. Clearance of peripheral blood PCMs (median clearance time, 216 hours; range, 84 to 492 hours) was significantly slower than that of parasitized erythrocytes (median, 96 hours; range, 36 to 168 hours) or PCNs (median, 72 hours; range, 0 to 168 hours; P < .0001). Intradermal PCM clearance times were the longest of all (median, 12 days; range, 6 to 23 days; significantly longer than peripheral blood PCM clearance, P < .001). Twenty-one (88%) patients still had signs, symptoms, or laboratory features of severe malaria after parasite clearance but before phagocyte pigment clearance. Sixteen of the 23 surviving patients (70%; 95% confidence interval, 50% to 87%) still had intraleukocytic malaria pigment on peripheral blood films 72 hours after parasite clearance. Thus, by determining the distribution of malaria pigment in peripheral blood and intradermal phagocytes, the time since effective antimalarial treatment started can be estimated. Microscopy for intraleukocytic pigment is valuable in the differential diagnosis of severe febrile illnesses in malarious areas where uncontrolled use of antimalarial drugs is widespread.
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Blackwater fever in southern Vietnam: a prospective descriptive study of 50 cases. Clin Infect Dis 1996; 23:1274-81. [PMID: 8953071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
We prospectively studied 50 Vietnamese patients with blackwater fever (BWF). All patients had fever and hemoglobinuria, 40 (80%) were jaundiced, 25 (50%) had hepatomegaly, 15 (34%) had splenomegaly, and 9 (18%) had hepatosplenomegaly. Twenty-one patients (42%) had impaired renal function, with creatinine clearances of < 50 mL/min/m2; however, only four (8%) developed oliguric renal failure, three (6%) of whom required dialysis. Forty-four patients (88%) developed anemia, which was severe (hematocrit, < 20% in 32 (64%). One patient died, representing a death rate for this once-feared disease that is considerably lower than that reported by earlier investigators. BWF was associated with quinine ingestion in 28 patients (56%), glucose-6-phosphate dehydrogenase (G6PD) deficiency in 27 (54%), and concurrent malaria infection in 16 (32%). There was no statistically significant difference in the severity of BWF associated with each of these three factors, as assessed by creatinine clearance and the hematocrit value on admission and by the number of units of blood transfused. There was considerable overlap in the occurrence of G6PD deficiency, quinine ingestion, and malaria, suggesting that these factors may interact and that it may not be justifiable to regard hemoglobinuria caused by G6PD deficiency as a separate syndrome.
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Abstract
BACKGROUND Neurological signs and symptoms are common in malaria, but observations in Vietnam and Thailand have pointed to a discrete transient neurological syndrome after recovery from severe infections. METHODS A prospective study of the post-malaria neurological syndrome (PMNS) was conducted at two centres in Vietnam over four years. Criteria for inclusion were recent symptomatic malaria infection with parasites cleared from blood (and in cases of cerebral malaria full recovery of consciousness), and development of neurological or psychiatric symptoms within two months after the acute illness. Half of the patients with severe falciparum malaria had been taking part in a randomised trial of antimalarials. FINDINGS Of 18,124 patients with falciparum malaria treated (1176 of whom had severe infections) 19 adults and three children had subsequent PMNS; in one patient it followed uncomplicated malaria and in 21 it followed severe malaria. The overall incidence (95% confidence interval) of PMNS after falciparum malaria at the main study centre was 1.2 per 1000 (0.7 to 1.8 per 1000) and relative risk (95% CI) for developing PMNS after severe versus uncomplicated falciparum malaria was 299 (40 to 2223). 13 patients had an acute confusional state or psychosis, six had one or more generalised convulsions, two had generalised convulsions followed by a long period of acute confusion, and one developed a fine tremor. At the time of PMNS diagnosis all patients were aparasitaemic. The syndrome was self-limiting, median duration 60 h (range 24-240). PMNS was associated with the use of oral mefloquine. In the randomised trial 4.4% (10/228) of patients with severe malaria who received mefloquine after parenteral treatment developed PMNS compared with 0.5% (1/210) of those who received quinine; relative risk 9.2 (95% CI 1.2 to 71.3, p = 0.012). INTERPRETATION Mefloquine is not the only risk factor for PMNS but it is a strong one. Where an effective alternative drug is available, mefloquine should not be used after treatment of severe malaria.
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Abstract
BACKGROUND Artemisinin (qinghaosu) and its derivatives are rapidly effective antimalarial drugs derived from a Chinese plant. Preliminary studies suggest that these drugs may be more effective than quinine in the treatment of severe malaria. We studied artemether in Vietnam, where Plasmodium falciparum has reduced sensitivity to quinine. METHODS We conducted a randomized, double-blind trial in 560 adults with severe falciparum malaria. Two hundred seventy-six received intramuscular quinine dihydrochloride (20 mg per kilogram of body weight followed by 10 mg per kilogram every eight hours), and 284 received intramuscular artemether (4 mg per kilogram followed by 2 mg per kilogram every eight hours). Both drugs were given for a minimum of 72 hours. RESULTS There were 36 deaths in the artemether group (13 percent) and 47 in the quinine group (17 percent; P = 0.16; relative risk of death in the patients given artemether, 0.74; 95 percent confidence interval, 0.5 to 1.11). The parasites were cleared more quickly from the blood in the artemether group (mean, 72 vs. 90 hours; P < 0.001); however, in this group fever resolved more slowly (127 vs. 90 hours, P < 0.001), the time to recovery from coma was longer (66 vs. 48 hours, P = 0.003), and the hospitalization was longer (288 vs. 240 hours, P = 0.005). Quinine treatment was associated with a higher risk of hypoglycemia (relative risk, 2.7; 95 percent confidence interval, 1.7 to 4.4; P < 0.001), but there were no other serious side effects in either group. CONCLUSIONS Artemether is a satisfactory alternative to quinine for the treatment of severe malaria in adults.
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Platelet deposition and fibrinogen binding on surfaces coated with heparin or friction-reducing polymers. AJNR Am J Neuroradiol 1996; 17:859-63. [PMID: 8733958 PMCID: PMC8337520] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The blood-contacting properties of polyethylene coated with a lubricious hydrophilic coating; an uncoated polyethylene; or a photoheparin-treated polyethylene-negative control sample were compared by measuring fibrinogen adsorption, antifibrinogen binding, and platelet attachment from human plasma. The polyethylene surfaces coated with a hydrophilic polymer were found to be similar to surfaces coated with heparin. Fibrinogen adsorption on the hydrophilic coating was 60% lower than adsorption on either the uncoated or heparin-coated polyethylene samples. Antifibrinogen binding from buffer to the hydrophilic coating was also reduced more than 85% from binding to uncoated polyethylene samples. Both the hydrophilic coating and heparin coating showed a reduction in platelet attachment by a factor of 100 over the uncoated sample as well as significantly reduced platelet activation.
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