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1.
J Econ Entomol ; 108(5): 2354-65, 2015 10.
Artigo em Inglês | MEDLINE | ID: mdl-26453724

RESUMO

In north-central Georgia, 13 species of woodboring beetles (Coleoptera: Cerambycidae: Cerambycinae) were attracted to multiple-funnel traps baited with ethanol and one of the following pheromones: (1) racemic 3-hydroxyhexan-2-one; (2) racemic 3-hydroxyoctan-2-one; and (3) syn-2,3-hexanediol. The following species were attracted to traps baited with ethanol and 3-hydroxyhexan-2-one: Anelaphus pumilus (Newman), Eburia quadrigeminata (Say), Euderces pini (Olivier), Knulliana cincta (Drury), Neoclytus mucronatus (F.), Neoclytus scutellaris (Olivier), and Xylotrechus colonus (F.). Clytus marginicollis Castelnau & Gory, and Anelaphus parallelus (Newman) were attracted to traps baited with ethanol and 3-hydroxyoctan-2-one, whereas traps baited with ethanol and syn-2,3-hexanediol were attractive to Anelaphus villosus (F.), A. parallelus, Neoclytus acuminatus (F.), Neoclytus jouteli jouteli Davis, and Megacyllene caryae (Gahan). Ethanol enhanced catches of seven cerambycid species in traps baited with syn-2,3-hexanediol and 3,2-hydroxyketones. Catches of bark and ambrosia beetles (Curculionidae: Scolytinae) in ethanol-baited traps were largely unaffected by the addition of syn-2,3-hexanediol and 3,2-hydroxyketone lures, except for two species. The mean catches of Hypothenemus rotundicollis Wood & Bright and Dryoxylon onoharaensum (Murayama) in ethanol-baited traps increased and decreased, respectively, with the addition of racemic 3-hydroxyoctan-2-one. Traps baited with ethanol and syn-2,3-hexanediol were attractive to Xylobiops basilaris (Say) (Bostrichidae) and Chariessa pilosa (Forster) (Cleridae), whereas Temnoscheila virescens (F.) (Trogossitidae) were attracted to traps baited with ethanol and 3-hydroxyhexan-2-one. The assassin bug, Apiomerus crassipes (F.) (Hemiptera: Reduviidae), was attracted to traps baited with ethanol and 3,2-hydroxyketones.


Assuntos
Besouros/efeitos dos fármacos , Etanol/farmacologia , Glicóis/farmacologia , Hexanonas/farmacologia , Controle de Insetos , Feromônios/farmacologia , Animais , Georgia , Gorgulhos/efeitos dos fármacos
2.
J Econ Entomol ; 108(4): 1837-51, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26470326

RESUMO

In 2007-2008, we examined the flight responses of wood-boring beetles (Coleoptera: Cerambycidae and Buprestidae) to multiple-funnel traps baited with the pine volatiles, ethanol, and α-pinene [85% (-)], and the bark beetle pheromones, racemic ipsenol and racemic ipsdienol. Experiments were conducted in mature pine stands in Canada (Ontario and New Brunswick) and the United States (Arkansas, Florida, Michigan, New Hampshire, North Carolina, Ohio, Tennessee, and Wisconsin). At each location, traps were deployed in 10 replicate blocks of four traps per block. The trap treatments were: 1) blank control; 2) ipsenol and ipsdienol; 3) ethanol and α-pinene; and 4) a quaternary blend of ipsenol, ipsdienol, ethanol, and α-pinene. Traps baited with the quaternary blend caught the greatest numbers of Acanthocinus nodosus (F.), Acanthocinus obsoletus (Olivier), Acmaeops proteus (Kirby), Astylopsis sexguttata (Say), Rhagium inquisitor (L.) (Cerambycidae), and Buprestis lineata (F.) (Buprestidae). Traps baited with ethanol and α-pinene caught the greatest numbers of Arhopalus rusticus (LeConte), Asemum striatum (L.), Tetropium spp., Xylotrechus sagittatus (Germar) (Cerambycidae), and Buprestis maculipennis Gory (Buprestidae) with minimal interruption by ipsenol and ipsdienol. Our results suggest that multiple-funnel traps baited with the quaternary lure blend of ipsenol, ipsdienol, ethanol, and α-pinene are effective for trapping various species of wood-boring beetles in pine forests of eastern North America, and may have utility in detection programs for adventive species in North America and overseas.


Assuntos
Besouros/efeitos dos fármacos , Florestas , Controle Biológico de Vetores , Feromônios/farmacologia , Monoterpenos Acíclicos , Álcoois/farmacologia , Animais , Monoterpenos Bicíclicos , Canadá , Etanol/farmacologia , Monoterpenos/farmacologia , Octanóis/farmacologia , Pinus/crescimento & desenvolvimento , Especificidade da Espécie , Estados Unidos
3.
Environ Entomol ; 52(1): 9-17, 2023 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-36611278

RESUMO

In 2011-2013, we determined the interactive effects of the cerambycid pheromones racemic syn-2,3-hexanediol, racemic 3-hydroxyhexan-2-one, and racemic 3-hydroxyoctan-2-one on trap catches of predators associated with bark and woodboring beetles in north Georgia and South Carolina. Temnoscheila virescens (F.) (Coleoptera: Trogossitidae) was attracted to traps baited with 3-hydroxyhexan-2-one; ethanol enhanced attraction. Traps baited with syn-2,3-hexanediol attracted Chariessa pilosa (Forster) (Coleoptera: Cleridae); attraction was interrupted by 3-hydroxyhexan-2-one. An assassin bug Apiomerus crassipes (F.) (Hemiptera: Reduviidae) was attracted to traps baited with 3-hydroxyhexan-2-one and/or 3-hydroxyoctan-2-one. Ethanol had no effect on trap catches of C. pilosa and A. crassipes. We compared response profiles of these predators to those of longhorn beetles captured in these same studies to provide insights on possible ecological interactions between these species.


Assuntos
Besouros , Reduviidae , Animais , Besouros/fisiologia , Feromônios/farmacologia , Etanol/farmacologia
4.
J Econ Entomol ; 115(3): 792-798, 2022 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-35394494

RESUMO

In 2012-2013, we assessed the interactive effects of the cerambycid pheromones syn-2,3-hexanediol, 3-hydroxyhexan-2-one, and 3-hydroxyoctan-2-one on catches of bark and ambrosia beetles (Coleoptera: Curculionidae) in ethanol-baited multiple-funnel traps in north Georgia and South Carolina. We found that catches for nine of eleven species of ambrosia beetles in ethanol-baited traps were either unaffected or enhanced by the addition of 3,2-hydroxyketones. Similarly catches of five species of bark beetles were either unaffected or enhanced by the addition of 3,2-hydroxyketones. In particular, catches of Xylosandrus crassiusculus (Motschulsky), Cnestus mutilatus (Blandford), and Monarthrum fasciatum (Say) in ethanol-baited traps increased with the addition of 3-hydroxyhexan-2-one and/or 3-hydroxyoctan-2-one. Catches of the bark beetles Hylocurus rudis (LeConte) and Hypothenemus rotundicollis (Eichhoff) were enhanced by the addition of 3-hydroxyhexan-2-one and 3-hydroxyoctan-2-one, respectively. syn-2,3-Hexanediol had no effect on catches of bark and ambrosia beetles in ethanol-baited traps. Our data provide support for the use of ethanol + cerambycid pheromones for targeting non-native species of bark and ambrosia beetles as well as cerambycids in detection programs.


Assuntos
Besouros , Gorgulhos , Ambrosia , Animais , Etanol/farmacologia , Georgia , Controle de Insetos , Feromônios/farmacologia , Casca de Planta
5.
Environ Entomol ; 51(1): 83-93, 2022 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-34636848

RESUMO

In 2016, we conducted three experiments to clarify the effects of 2,3-hexanediols isomers on trap catches of Neoclytus acuminatus (F.) (Coleoptera: Cerambycidae). We also noted the effects of the isomers on trap catches of other cerambycids and associated species of predators and competitors. Catches of N. acuminatus in traps baited with ethanol + syn-2,3-hexanediol + racemic 3-hydroxyoctan-2-one were reduced with the addition of anti-2,3-hexanediol, an attractant for Curius dentatus Newman (Coleoptera: Cerambycidae). A fourth experiment conducted in 2017 verified that racemic 3-hydroxyoctan-2-one increases catches of N. acuminatus in traps baited with ethanol + syn-2,3-hexanediol. The addition of anti-2,3-hexanediol increased catches of Knulliana cincta (Drury) (Coleoptera: Cerambycidae) in traps baited with ethanol + racemic 3-hydroxyoctan-2-one, whereas attraction of Neoclytus scutellaris (Olivier) to traps baited with ethanol + racemic 3-hydroxyhexan-2-one was reduced by syn-2,3-hexanediol. Trap catches of the beetle predators Chariessa pilosa (Forster), Enoclerus ichneumonus (F.), and Madoniella dislocata (Say) (Coleoptera: Cleridae) were affected by 2,3-hexanediol isomers, whereas other common predators were unaffected by the isomers. Attraction of the bostrichid Xylobiops basilaris (Say) (Coleoptera: Bostrichidae) was increased by the 2,3-hexanediols; the relative effect of the two isomeric blends was dependent on trap co-baits of 3-hydroxy-2-ketones. The two enantiomeric blends of 2,3-hexanediol had minimal effects on catches of most species of ambrosia beetles, whereas the 3-hydroxy-2-ketones affected trap catches of some species.


Assuntos
Besouros , Animais , Etanol/farmacologia , Controle de Insetos , Feromônios/farmacologia , Sudeste dos Estados Unidos
6.
J Econ Entomol ; 113(1): 273-280, 2020 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-31617908

RESUMO

In north-central Georgia, trap height affected catches of some species of bark and woodboring beetles (Coleoptera) in traps baited with lures used in surveillance programs to detect non-native forest insects. Traps were placed within the canopy and understory of mature oak trees (Quercus spp.) with collection cups placed 18-23 m above ground level (AGL), and 0.3-0.5 m AGL, respectively. Traps were baited with ethanol to target ambrosia beetles (Curculionidae: Scolytinae) in one experiment, ethanol + syn-2,3-hexanediol + racemic 3-hydroxyhexan-2-one + racemic 3-hydroxyoctan-2-one to target hardwood woodborers (Cerambycidae) in a second experiment, and α-pinene + racemic ipsenol + racemic ipsdienol to target pine bark beetles (Curculionidae) and woodborers (Cerambycidae) in a third experiment. Canopy traps were more effective than understory traps for detecting Cnestus mutilatus (Blandford) (Curculionidae), Neoclytus scutellaris (Olivier), and Monochamus titillator (F.) (Cerambycidae). The reverse was true for Xylosandrus crassiusculus (Motschulsky), Dendroctonus terebrans (Olivier) (Curculionidae), and Neoclytus acuminatus (F.) (Cerambycidae). Catches of a third group which included Hylobius pales (Herbst), Ips grandicollis (Eichhoff) (Curculionidae), Neoclytus mucronatus (F.), and Anelaphus pumilus (Newman) (Cerambycidae) were largely unaffected by trap height. Similar patterns were noted for species of Cleridae, Scarabaeidae, Trogossitidae, and Zopheridae but not Histeridae or Tenebrionidae (Coleoptera). Catches of the bee assassin Apiomerus crassipes (F.) (Hemiptera: Reduviidae) in traps baited with the hardwood borer blend were greater in canopy traps than in understory traps.


Assuntos
Besouros , Gorgulhos , Animais , Georgia , Controle de Insetos , Feromônios , Casca de Planta
7.
J Econ Entomol ; 110(5): 2119-2128, 2017 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-28981676

RESUMO

The effectiveness of a four-component "super lure" consisting of ethanol (E) and the cerambycid pheromones syn-2,3-hexanediol (D6), racemic 3-hydroxyhexan-2-one (K6), and racemic 3-hydroxyoctan-2-one (K8) on trap catches of Cerambycidae (Coleoptera) was determined in southeast United States with seven trapping experiments in 2011-2013. We captured 74 species of longhorn beetles in our three-year study. Ethanol significantly increased the mean catches of seven species and increased the number of cerambycid species detected. Traps with the "super lure" were effective for 8 of 13 species of Cerambycidae previously shown to be attracted to binary combinations of ethanol plus one of the three pheromones. However, the "super lure" was less effective for the remaining five species with catch reductions of 40-90% compared with combinations of ethanol and one or two of the pheromones. For example, K6 + K8 lures reduced catches of Anelaphus villosus (F.) in traps with E + D6 by 90%. Similarly, catches of Anelaphus pumilus (Newman) in traps with E + K6 + D6 were reduced by 50% with the addition of K8. Catches of Knulliana cincta (Drury) in traps with K6 + K8 lures were interrupted by D6, an effect negated by the addition of ethanol. Given the interruptive effects on trap catches of some species when lures are combined in a single trap, developing optimal lure blends to maximize detection efficacy will be a challenge for managers of detection programs for non-native invasive species of longhorn beetles.


Assuntos
Comportamento Animal/efeitos dos fármacos , Besouros/efeitos dos fármacos , Glicóis/farmacologia , Hexanonas/farmacologia , Cetonas/farmacologia , Feromônios/farmacologia , Animais , Controle de Insetos/instrumentação , Sudeste dos Estados Unidos
8.
J Econ Entomol ; 109(3): 1205-1214, 2016 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-27106224

RESUMO

Detection tools are needed for Monochamus species (Coleoptera: Cerambycidae) because they are known to introduce pine wilt disease by vectoring nematodes in Asia, Europe, and North America. In 2012-2014, we examined the effects of the semiochemicals monochamol and ipsenol on the flight responses of the sawyer beetles Monochamus carolinensis (Olivier), Monochamus clamator (LeConte), Monochamus mutator LeConte, Monochamus notatus (Drury), Monochamus obtusus Casey, Monochamus scutellatus (Say), and Monochamus titillator (F.) complex (Coleoptera: Cerambycidae) to traps baited with α-pinene. Experiments were set in pine forests in New Brunswick and Ontario (Canada), and Arizona, Georgia, Michigan, Montana, Oregon, South Carolina, Utah, and Washington (United States). In brief, 40 traps were placed in 10 blocks of 4 traps per block per location. Traps were baited with: 1) α-pinene; 2) α-pinene + monochamol; 3) α-pinene + ipsenol; and 4) α-pinene + monochamol + ipsenol. Monochamol increased catches of six species and one species complex of Monochamus with an additive effect of ipsenol for five species and one species complex. There was no evidence of synergy between monochamol and ipsenol on beetle catches. Monochamol had no effect on catches of other Cerambycidae or on any associated species of bark beetles, weevils, or bark beetle predators. We present a robust data set suggesting that the combination of α-pinene, ipsenol, and monochamol may be a useful lure for detecting Monochamus species.

9.
Am J Clin Pathol ; 99(6): 687-8, 1993 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8322702

RESUMO

Levels of factor IX:C and factor IX:Ag were measured in 120 healthy subjects with an age range of 1 to 67 years. Levels of factor IX:C were lowest in prepubertal subjects, then reached a plateau in early adult life with a secondary increase in later adult life (> 45 years). Changes in factor IX:Ag showed a similar trend. Factor IX:Ag disproportionately increased in early adult life, however, with a less pronounced increase in later life, resulting in peaking of the ratio in early adult life. It is suggested that caution be exercised in interpreting low normal factor IX:C levels in prepubertal children, and that interpretation of ratios of antigenic to coagulant activity may need to take subject age into consideration.


Assuntos
Envelhecimento/sangue , Fator IX/análise , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Fator IX/metabolismo , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Valores de Referência
10.
Am J Clin Pathol ; 89(5): 655-9, 1988 May.
Artigo em Inglês | MEDLINE | ID: mdl-3358370

RESUMO

Platelet aggregation studies are usually performed in either electrical impedance or optical systems and the release reaction assessed by quantitating adenosine triphosphate (ATP) from luminesence produced by the firefly luciferin-luciferase system. In evaluating the results of such studies, attention is paid to a variety of parameters such as the slope of the aggregation response and the maximum aggregation expressed as percent light transmission in optical and as Ohms in electrical impedance systems. Although threshold platelet counts are frequently cited below which the performance of these studies is technically difficult, the influence of the platelet count within the normal range on the results of such studies has not been prospectively addressed. This study examines the relationship between the aggregation response, ATP release and the platelet count in a lumi-impedance system. It is clear that the platelet count influences the results in this system and requires consideration in the interpretation if an erroneous conclusion is to be avoided.


Assuntos
Trifosfato de Adenosina/sangue , Agregação Plaquetária , Contagem de Plaquetas , Testes de Função Plaquetária/instrumentação , Difosfato de Adenosina , Adolescente , Adulto , Idoso , Colágeno , Condutividade Elétrica , Feminino , Hemofilia A/sangue , Transtornos Hemorrágicos/sangue , Humanos , Medições Luminescentes , Masculino , Pessoa de Meia-Idade , Agregação Plaquetária/efeitos dos fármacos
11.
Am J Clin Pathol ; 92(5): 676-9, 1989 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-2816822

RESUMO

The method of sample collection and time interval from venipuncture to test performance is considered to be important in platelet function testing. Platelet function studies can be performed in whole blood with the use of an impedance lumi-aggregometer, and an examination of the influence of these variables on the outcome of such a study is important. Twelve healthy donors had blood drawn with the use of conventional approach for platelet function testing and a Vacutainer method. Platelet function studies were performed at three time points over a three-hour period. No significant differences in results were observed between the methods of collection and the time to test performance. It is concluded that for platelet function screening in whole blood, with the use of an impedance lumi-aggregometer, a Vacutainer sample maintained at room temperature and tested within three hours is satisfactory.


Assuntos
Coleta de Amostras Sanguíneas/métodos , Agregação Plaquetária , Testes de Função Plaquetária/métodos , Trifosfato de Adenosina/sangue , Adulto , Feminino , Humanos , Masculino , Agregação Plaquetária/efeitos dos fármacos , Ristocetina/farmacologia , Trombina/farmacologia , Fatores de Tempo , Doenças de von Willebrand/sangue
12.
Am J Clin Pathol ; 108(1): 74-7, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9208981

RESUMO

Factor V(Leiden) is the most common abnormality detected in patients examined because of hereditary thrombophilia. The most widely used clot-based screening test is based on the activated partial thromboplastin (aPTT) time. This test has a low sensitivity. A comparison of the aPTT-based test with a Russell viper venom time test (RVVT) was performed in matched samples. All samples were analyzed by polymerase chain reaction (PCR) for the factor V(Leiden) defect. We studied 139 samples, of which 109 were PCR-negative; 30 were PCR-positive. Using the manufacturer's suggested threshold ratio of 2, the aPTT test showed a sensitivity of 0.43, a specificity of 0.86, and a positive predictive value (PPV) of 0.97. The RVVT test had a sensitivity of 1.0, a specificity of 0.95, and a PPV of 0.91. Segregation of a subpopulation of this study population into ABO group O vs non-group O showed an effect of ABO group on the aPTT test but not on the RVVT test, consistent with an influence of factor VIII clotting (factor VIII:C) on the aPTT test. The RVVT test seems superior to the unmodified aPTT test as a screening test for factor V(Leiden).


Assuntos
Fator V/análise , Tempo de Tromboplastina Parcial , Tempo de Protrombina , Trombose/diagnóstico , Testes Genéticos , Humanos , Mutação , Reação em Cadeia da Polimerase , Valor Preditivo dos Testes , Sensibilidade e Especificidade , Trombose/genética
13.
Am J Clin Pathol ; 110(5): 673-82, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9802354

RESUMO

The range of tests used in the evaluation of thrombophilia has been altered by the recent recognition of common genetic defects predisposing to thrombosis such as factor VLeiden (FVR506Q), enzyme deficiencies causing hyperhomocysteinemia, and improvement in the sensitivity and utilization of assays for antiphospholipid antibodies. In this study, the outcomes of laboratory evaluation of 402 patients with thrombophilia were reviewed and correlated with clinical data. A predisposing factor was present (positive diagnosis, group A) in 110 patients (27%), the test results of 111 patients (28%) could not be definitively interpreted (equivocal results, group B), and the test results of 181 (45%) were normal (group C). The median age of the group A patients was 48 years (range, 3.7-88 years), suggesting that evaluation of patients over the age of 50 is worthwhile. Of the 110 patients in group A, 84% had single defects and 16% had combined defects. The most common defect was factor VLeiden (44 patients). Equal numbers of patients presenting with arterial and venous thromboses were evaluated. Patients with arterial events were less likely to have a definable laboratory defect (33 of 132 [25%]) than were those with venous events (50 of 136 [37%]). Factor VLeiden was the most frequent finding in patients with venous events, and lupus anticoagulant or anticardiolipin antibodies were the most frequent findings in patients with arterial events. Positive diagnoses were made in patients on anticoagulants, indicating that this should not preclude investigation. Our study confirms the need for thorough evaluation to assess thrombotic risk, and it reflects the impact of newly identified thrombophilic disorders on the expected outcome of laboratory evaluation for thrombophilia.


Assuntos
Trombofilia/diagnóstico , Trombose/genética , Resistência à Proteína C Ativada/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Anticardiolipina/análise , Anticorpos Antifosfolipídeos/análise , Anticoagulantes/uso terapêutico , Criança , Pré-Escolar , Fator V/análise , Predisposição Genética para Doença , Homocisteína/sangue , Humanos , Inibidor de Coagulação do Lúpus/análise , Pessoa de Meia-Idade , Mutação , Trombofilia/genética , Tromboflebite/diagnóstico , Tromboflebite/genética , Trombose/diagnóstico
14.
Am J Clin Pathol ; 93(4): 522-5, 1990 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2321583

RESUMO

Von Willebrand's disease is categorized into types and subtypes based on multimeric analysis of plasma von Willebrand's factor. Such categorization is of value because both the mode of inheritance and the choice of therapeutic material differ between subtypes. The Type IIB variant is characterized by hypersensitivity in vitro to ristocetin and thrombocytopenia after administration of desmopressin (DDAVP). Hypersensitivity to ristocetin has also been described in Type I variants but without thrombocytopenia after DDAVP. This report describes a new Type II variant characterized by the converse situation, absence of hypersensitivity to ristocetin in vitro but transient thrombocytopenia after intravenous administration of DDAVP.


Assuntos
Desamino Arginina Vasopressina/efeitos adversos , Hipersensibilidade a Drogas/etiologia , Ristocetina/efeitos adversos , Trombocitopenia/induzido quimicamente , Doenças de von Willebrand/sangue , Desamino Arginina Vasopressina/administração & dosagem , Hipersensibilidade a Drogas/sangue , Feminino , Humanos , Infusões Intravenosas , Masculino , Linhagem , Agregação Plaquetária/efeitos dos fármacos , Contagem de Plaquetas , Doenças de von Willebrand/classificação , Doenças de von Willebrand/genética , Fator de von Willebrand/análise , Fator de von Willebrand/genética
15.
Am J Clin Pathol ; 93(4): 548-51, 1990 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2321587

RESUMO

The examination of the interaction between ristocetin and platelets generally is performed in an optical aggregometer where aggregate formation is detected by a change in turbidity. Ristocetin also will induce conductivity changes in an impedance aggregometer with either fresh whole blood or fresh platelet-rich plasma due to aggregate attachment to the electrical probe. Formaldehyde-fixed platelets, however, do not attach, and although fresh platelets agglutinate at extremes of pH, probe adhesion does not occur unless the pH is within a certain range. Incubation of platelet preparations with neuraminidase, colchicine, or cytochalasin-b affects neither aggregate formation nor probe adherence. Incubation of platelet preparations with a fibronectin tetrapeptide inhibitor eliminates aggregate formation in response to collagen but is without effect on ristocetin-induced attachment of aggregates to the impedance probe. It is suggested that the ability of platelet aggregates to attach to an impedance probe in response to ristocetin is dependent on additional aspects of the functional integrity of platelet preparations and that these changes required for probe adherence may have in vivo significance.


Assuntos
Adesividade Plaquetária/efeitos dos fármacos , Agregação Plaquetária/efeitos dos fármacos , Testes de Função Plaquetária/instrumentação , Ristocetina/farmacologia , Plaquetas/fisiologia , Humanos
16.
Am J Clin Pathol ; 91(1): 79-81, 1989 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2491926

RESUMO

An influence of the ABO blood group on von Willebrand and Factor VIII:C levels is known. Von Willebrand factor interacts with at least two platelet membrane receptors, but the effect of ABO group on platelet function is an unstudied area. The authors examined platelet function in 40 plateletpheresis donors using an impedance lumi-aggregometer. Aggregation responses to collagen, adenosine diphosphate (ADP), and ristocetin were measured and the adenosine triphosphate (ATP) release to thrombin. Twenty donors were Group O and 20 were Group A. Measurements of von Willebrand factor antigen (vWf:Ag), Factor VIII: C, and ristocetin co-factor (RiCoF) in the same group showed reduced levels of vWf:Ag and Factor VIII:C in Group O, as previously reported. The aggregation response to collagen and ADP and the release of ATP did not differ. The aggregation response to ristocetin, however, was better in Group O than in Group A despite the lower vWf:Ag levels. The explanation for this is unclear, but the data suggest an influence of blood group antigens on the interaction between von Willebrand's factor and platelets.


Assuntos
Sistema ABO de Grupos Sanguíneos , Agregação Plaquetária , Fator de von Willebrand/fisiologia , Fator VIII/análise , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Contagem de Plaquetas , Glicoproteínas da Membrana de Plaquetas/fisiologia , Ristocetina , Fator de von Willebrand/análise
17.
Am J Clin Pathol ; 92(6): 794-7, 1989 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2589246

RESUMO

Platelet function in platelet-rich plasma may be evaluated using an optical or electrical impedance method. Platelet function in whole blood may be studied using an impedance or particle counter method. A comparison of these techniques in whole blood has not been performed. Twenty-four healthy subjects were studied using both techniques over a range of concentrations of collagen and adenosine diphosphate (ADP). Although broad similarities exist, discordant patterns occur in individual subjects. The particle counter method is capable of detecting small aggregates and thus is more sensitive. The impedance aggregometer detects only larger aggregate formation. These techniques are complementary rather than competitive and may have considerable potential in profiling platelet function.


Assuntos
Condutividade Elétrica/fisiologia , Agregação Plaquetária/fisiologia , Contagem de Plaquetas , Difosfato de Adenosina/metabolismo , Colágeno/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
18.
Am J Clin Pathol ; 109(4): 387-91, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9535390

RESUMO

Factor V Leiden (FVR506Q) is a genetic defect in the factor V (FV) molecule that confers resistance to proteolysis by activated protein C (APC) and is the most common abnormality detected in patients studied for hereditary thrombophilia. The initial screening test for this abnormality was a comparison of the activated partial thromboplastin time (APTT) in the presence and absence of APC, expressed as a ratio. But this has been shown to lack sensitivity for the FV mutation. Other clot-based screening tests, such as the modified APTT, using FV-deficient plasma, or the Russell viper venom (RVV) time assay have improved sensitivity. Eighty-seven samples were studied using the RVV-based assay. This assay was performed on platelet-poor plasma (PPP-RVV) and whole blood (WB-RVV). All samples were analyzed by polymerase chain reaction (PCR) for the FV Leiden defect: 77 were PCR negative; 10 were PCR positive. Using a threshold ratio of 1.8, all samples were correctly categorized in the PPP-RVV and the WB-RVV tests, showing an observed sensitivity and specificity of 1.0. These results suggest that an RVV-based assay using whole blood could be an effective screening test for this common abnormality.


Assuntos
Fator V/análise , Tempo de Protrombina , Trombose/diagnóstico , Tempo de Coagulação do Sangue Total , Adolescente , Adulto , Idoso , Aprotinina/farmacologia , Relação Dose-Resposta a Droga , Fator V/genética , Feminino , Fibrinolíticos/farmacologia , Testes Genéticos , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Valor Preditivo dos Testes , Proteína C/farmacologia , Sensibilidade e Especificidade , Trombose/genética
19.
Thromb Res ; 68(4-5): 393-8, 1992 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-1290167

RESUMO

Levels of plasma Von Willebrand Factor (vWF) are known to be influenced by ABO Blood Group but such an influence on platelet vWF is not known. Forty-three healthy donors had blood drawn for measurement of plasma and platelet vWF, both antigenic (vWF:Ag) and functional (RCo). Twenty-six were Group O and seventeen were Group A. Groups did not differ in age, platelet count, hemoglobin, white cell counts, platelet rich plasma counts nor length of in vitro storage of samples prior to assay. Plasma levels of vWF:Ag and RCo was lower in Group O as expected. Platelet RCo was lower in Group O and such a trend was present for vWF:Ag. This influence of ABO Groups on platelet vWF was modest compared to that on plasma vWF.


Assuntos
Sistema ABO de Grupos Sanguíneos/metabolismo , Plaquetas/metabolismo , Fator de von Willebrand/análise , Humanos , Plasma/metabolismo
20.
Thromb Res ; 61(1): 23-7, 1991 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-2020937

RESUMO

Salsalate in a non-acetylated salicylate with activity as an antirheumatic agent. The hemostatic effects of this agent were studied in twelve healthy subjects and nine patients with hemophilia A. Healthy subjects showed no change in bleeding time, platelet aggregation response to adenosine diphosphate (ADP) or collagen, or adenosine triphosphate (ATP) release in response to arachidonic acid as measured in an impedance whole blood lumi-aggregometer. The patients with hemophilia A showed no bleeding time prolongation nor an effect on ADP or collagen induced platelet aggregation in platelet rich plasma. It is concluded that this agent may be useful in the treatment of arthritis in patients with hereditary coagulation disorders.


Assuntos
Hemofilia A/tratamento farmacológico , Hemostasia/efeitos dos fármacos , Salicilatos/farmacologia , Artrite/tratamento farmacológico , Artrite/etiologia , Coagulação Sanguínea/efeitos dos fármacos , Hemofilia A/sangue , Hemofilia A/complicações , Humanos , Masculino , Agregação Plaquetária/efeitos dos fármacos , Salicilatos/efeitos adversos , Salicilatos/uso terapêutico
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