Ultrastructural studies of the hemocytes of Panstrongylus megistus (Hemiptera: Reduvidae)

Ultrastructural analyses revealed the presence of six hemocyte types in the hemolymph of Panstrogylus megistus, partially confirming our previous results obtained through light microscopy. Prohemocytes: small, round hemocytes with a thin cytoplasm layer, espcieally rich in free ribosomes and poor in membranous systems. Plasmatocytes: polymorphic cells, whose cytoplasm contains many lysosomes and a well developed rough endoplasmic reticulum (RER).They are extremely phagocytic. Sometimes, they show a large vacuolation. Granulocytes: granular hemocytes whose granules show different degrees of electrondensity. Most of them, have an internal structuration. Coagulocytes: oval or elongated hemocytes, which show pronounced perinuclear cisternae as normally observed in coagulocytes. The cytoplasm is usually electrondense, poor in membranous systems and contains many labile granules. Oenocytoids: large and very stable hemocytes, whose homogeneous cytoplasme is rich in loose ribosomes and poor in membranous systems. Adipohemocytes: large cells, containing several characteristic lipid droplets. The cytoplasm is also rich in glycogen, RER and large mitochondria. The total and differential hemocyte count (THC and DHC) were also calculated for this reduviid. THC increases from 2,900 hemocytes/cubic millimeter of hemolymph in the 4th intar to 4,350 in the 5th and then, decreases to 1,950 in the adults. Plasmatocytes and coagulocytes are the predominant hemocyte types.

Estudo morfológico e quantitativo dos hemócitos em larvas de Diatraea saccharalis (Fabricius) (Lepidoptera, Pyralidae)

Hemocytes of Diatraea saccharalis larvae aging from 13 to 26 days old were morphological and quantitatively characterized by phase contrast microscopy. Six hemocyte types were described and identified as: prohemocytes (PR), plasmatocytes (PL), granulocytes (GR), oenocytoides (OE). spherulocytes (SP) and verm cells (VE). The total hemocyte counts showed no significant difference in the number of these cells along the normal development of the larvae. However, the relative number of different circulating hemocyte types fluctuated, and it could be expressed as: PL > GR > SP> PR > VE > OE in larvae up to 14 days old; and as: GR > SP > PL > VE > OE > PR in those older than 24 days.

Ultrastructural and quantitative studies of hemocytes in the sugarcane borer, Diatraea saccharalis (Lepidoptera: Pyralidae)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Hemocyte types and total and differential counts in unparasitized and parasitized Anastrepha obliqua (Diptera, Tephritidae) larvae

Os tipos de hemócitos e as contagens total e diferencial foram estudados em larvas parasitadas e não parasitadas de Anastrepha obliqua pertencentes ao início e ao final da terceira fase. em ambas as fases do desenvolvimento, tanto em larvas parasitadas quanto nas não parasitadas, foram observados pró-hemócitos, plasmatócitos, granulócitos, adipo-hemócitos, esferulócitos e oenocitóides. A presença de divisões mitóticas indica os pró-hemócitos como células-tronco. Pró-hemócitos, plasmatócitos e granulócitos são as células mais numerosas na hemolinfa de A. obliqua. Foi observada diferença no número total de hemócitos entre larvas parasitadas e não parasitadas apenas no final da terceira fase.

Morphological and quantitative aspects of nodule formation in hemolymph of the blowfly Chrysomya megacephala (Fabricius, 1794)

Insects manifest effective immune responses that include both cellular and humoral components. Morphological and quantitative aspects of cellular and Immoral cooperation during nodule formation in Chrysomya megacephala hemolymph against Saccharomyces cerevisae yeast cells were demonstrated for the first time. The analyses were performed in non-injected larvae (NIL), saline-injected larvae (SIL) and yeast-injected larvae (YIL). The hemolymph of injected groups was collected 0.5, 1, 2, 4, 12, 24, 36, or 48-h post-injection. Morphological aspects of YIL nodulation were investigated using transmission electron microscopy (TEM). Quantitative analyses consisted of total (THC) and differential hemocyte counts (DHC) in all the groups and total yeast count (TYC) in YIL, which were performed in an improved Neubauer chamber. Nodule formation was initiated at approximately 2-h post-injection. Twelve hours after the injection, TEM revealed the presence of an amorphous membrane, at the same time that circulating hemocyte number decreased significantly contrasting the increase of yeast number. Our results showed the ability of C megacephala hemolymph to perform humoral encapsulation when hemocyte population is insufficient to eliminate the microorganisms, warranting consideration in future investigations on the relative roles played by cellular and humoral elements of innate immunity of this calliphorid. (c) 2007 Elsevier B.V. All rights reserved.

Insect/Bt-cotton interactions: Are immunological variables and hemocyte ultrastructure in Podisus nigrispinus (Hemiptera: Pentatomidae) affected?

Recent studies have shown that ingestion by the army worm Spodoptera frugiperda of Cry1Ac toxin from Bt cotton promotes histochemical and ultrastructural changes in the digestive cells of the predatory pentatomid bug Podisus nigrispinus. Therefore, mindful of the changes in the midgut of the predator, which represents the first line of defence in this insect, our aim was to test the hypothesis that the consumption of Bt cotton-fed S. frugiperda by P. nigrispinus might lead to alterations in components of the immune system of P. nigrispinus. The Cry1Ac toxin level in the leaves of Bt cotton, nitric oxide, phenoloxidase activity, and total proteins were quantified by ELISA. Total and differential hemocyte counts were evaluated, and hemocyte ultrastructure analysis was undertaken. We found that ingestion of the prey fed daily with approximately 23 ± 0.70 ng g-1 Cry1Ac by wet weight of leaves, and expressed by the Bt cotton, induces small ultrastructural changes in the predator's granulocytes and plasmatocytes. However, these changes did not affect the total number and differential and humoral variables analyzed for the bug's hemocytes. © 2013 Copyright Taylor and Francis Group, LLC.

Dietary Levamisole Influenced Hematological Parameters of Juvenile Pacu, Piaractus mesopotamicus (Holmberg 1887)

Diseases outbreaks are a major concern in intensive fish farming because fish are exposed to stressors which may negatively affect their physiology. This study set out to determine effects of dietary levamisole (Levamisole HCl; SIGMA (R)) on performance and hematology of pacu, Piaractus mesopotamicus, juveniles. Fish (55.94 g) were stocked into 24 plastic aquaria (500 L; 15 fish per aquarium) and fed for 30 d with a commercial diet with 0, 50, 100, 200, 400, and 800 mg/kg levamisole, and for an extra 15 d, with a control diet in a totally randomized design trial (n = 4). Biometrical and hematological data were collected. No significant differences in growth parameters were recorded for either control or supplemented diets. Hematological parameters, such as hemoglobin, plasma glucose, white blood count (WBC), and differential leukocyte count were influenced (P < 0.05) levamisole. WBC, lymphocytes, neutrophils, monocytes, eosinophils, and special granulocytic cell numbers decreased significantly after 15 d. Dietary levamisole at 100 mg/kg diet for 15 d increased leukocyte production in juvenile pacu. However, levamisole administration for more than 15 d presented toxicity to lymphopoietic tissues. Information about long-period administration, mode of action in weight gain, effects on hematology of levamisole in freshwater fish nutrition are scarce and necessary for its safe use in aquaculture.

Anti-inflammatory effect of bee venom on antigen-induced arthritis in rabbits: Influence of endogenous glucocorticoids

Aim of the study: This study assessed the involvement of endogenous glucocorticoids (GCs) in the anti-arthritic properties of bee venom (BV) on antigen-induced arthritis (AIA) in rabbits. Materials and methods: BV (1.5-6 mu g/kg/day) was injected for 7 days before AIA induction, whereas the control group received sterile saline. The total and differential leukocyte count. PGE(2) levels in synovial fluid and synovial membrane cell infiltrate were evaluated. The contribution of GCs to BV action was assessed in rabbits treated with BV plus metyrapone, an inhibitor of GC synthesis, or RU-38 486, a steroid antagonist. Results: Treatment with BV (1.5 mu g/kg/day) reduced the leukocyte count and PGE2 level (18571 +/- 1909 cells/mm(3) and 0.49 +/- 0.05 ng/mL, respectively) as well as the cellular infiltrate compared with the control group (40968 +/- 5248 cells/mm(3) and 2.92 +/- 0.68 ng/mL, p < 0.05). The addition of metyrapone to BV treatment completely reversed the inhibition of AIA, whereas RU-38 486 was ineffective. Conclusion: Our data show that bee venom treatment prevents the development of antigen-induced arthritis in rabbits through the action of GCs. (C) 2010 Elsevier Ireland Ltd. All rights reserved.

Predicting Bacteremia in Children With Cancer and Fever in Chemotherapy-induced Neutropenia: Results of the Prospective Multicenter SPOG 2003 FN Study.

STUDY AIM:: To develop a score predicting the risk of bacteremia in cancer patients with fever and neutropenia (FN), and to evaluate its performance. METHODS:: Pediatric patients with cancer presenting with FN induced by nonmyeloablative chemotherapy were observed in a prospective multicenter study. A score predicting the risk of bacteremia was developed from a multivariate mixed logistic regression model. Its cross-validated predictive performance was compared with that of published risk prediction rules. RESULTS:: Bacteremia was reported in 67 (16%) of 423 FN episodes. In 34 episodes (8%), bacteremia became known only after reassessment after 8 to 24 hours of inpatient management. Predicting bacteremia at reassessment was better than prediction at presentation with FN. A differential leukocyte count did not increase the predictive performance. The reassessment score predicting future bacteremia in 390 episodes without known bacteremia used the following 4 variables: hemoglobin ≥90 g/L at presentation (weight 3), platelet count <50 G/L (3), shaking chills (5), and other need for inpatient treatment or observation according to the treating physician (3). Applying a threshold ≥3, the score-simplified into a low-risk checklist-predicted bacteremia with 100% sensitivity, with 54 episodes (13%) classified as low-risk, and a specificity of 15%. CONCLUSIONS:: This reassessment score, simplified into a low-risk checklist of 4 routinely accessible characteristics, identifies pediatric patients with FN at risk for bacteremia. It has the potential to contribute to the reduction of use of antimicrobials in, and to shorten the length of hospital stays of pediatric patients with cancer and FN.

Predicting adverse events in children with fever and chemotherapy-induced neutropenia: the prospective multicenter SPOG 2003 FN study.

PURPOSE To develop a score predicting the risk of adverse events (AEs) in pediatric patients with cancer who experience fever and neutropenia (FN) and to evaluate its performance. PATIENTS AND METHODS Pediatric patients with cancer presenting with FN induced by nonmyeloablative chemotherapy were observed in a prospective multicenter study. A score predicting the risk of future AEs (ie, serious medical complication, microbiologically defined infection, radiologically confirmed pneumonia) was developed from a multivariate mixed logistic regression model. Its cross-validated predictive performance was compared with that of published risk prediction rules. Results An AE was reported in 122 (29%) of 423 FN episodes. In 57 episodes (13%), the first AE was known only after reassessment after 8 to 24 hours of inpatient management. Predicting AE at reassessment was better than prediction at presentation with FN. A differential leukocyte count did not increase the predictive performance. The score predicting future AE in 358 episodes without known AE at reassessment used the following four variables: preceding chemotherapy more intensive than acute lymphoblastic leukemia maintenance (weight = 4), hemoglobin > or = 90 g/L (weight = 5), leukocyte count less than 0.3 G/L (weight = 3), and platelet count less than 50 G/L (weight = 3). A score (sum of weights) > or = 9 predicted future AEs. The cross-validated performance of this score exceeded the performance of published risk prediction rules. At an overall sensitivity of 92%, 35% of the episodes were classified as low risk, with a specificity of 45% and a negative predictive value of 93%. CONCLUSION This score, based on four routinely accessible characteristics, accurately identifies pediatric patients with cancer with FN at risk for AEs after reassessment.

Predicting Adverse Events in Children with Fever and Chemotherapy-Induced Neutropenia. Results of the Prospective Multicenter SPOG 2003 FN Study

PURPOSE To develop a score predicting the risk of adverse events (AEs) in pediatric patients with cancer who experience fever and neutropenia (FN) and to evaluate its performance. PATIENTS AND METHODS Pediatric patients with cancer presenting with FN induced by nonmyeloablative chemotherapy were observed in a prospective multicenter study. A score predicting the risk of future AEs (ie, serious medical complication, microbiologically defined infection, radiologically confirmed pneumonia) was developed from a multivariate mixed logistic regression model. Its cross-validated predictive performance was compared with that of published risk prediction rules. Results An AE was reported in 122 (29%) of 423 FN episodes. In 57 episodes (13%), the first AE was known only after reassessment after 8 to 24 hours of inpatient management. Predicting AE at reassessment was better than prediction at presentation with FN. A differential leukocyte count did not increase the predictive performance. The score predicting future AE in 358 episodes without known AE at reassessment used the following four variables: preceding chemotherapy more intensive than acute lymphoblastic leukemia maintenance (weight = 4), hemoglobin > or = 90 g/L (weight = 5), leukocyte count less than 0.3 G/L (weight = 3), and platelet count less than 50 G/L (weight = 3). A score (sum of weights) > or = 9 predicted future AEs. The cross-validated performance of this score exceeded the performance of published risk prediction rules. At an overall sensitivity of 92%, 35% of the episodes were classified as low risk, with a specificity of 45% and a negative predictive value of 93%. CONCLUSION This score, based on four routinely accessible characteristics, accurately identifies pediatric patients with cancer with FN at risk for AEs after reassessment.

Monitoring inflammatory bowel disease activity: clinical activity is judged to be more relevant than endoscopic severity or biomarkers.

BACKGROUND: There is increasing evidence for the clinical relevance of mucosal healing (MH) as therapeutic treatment goal in inflammatory bowel disease (IBD). We aimed to investigate by which method gastroenterologists monitor IBD activity in daily practice. METHODS: A questionnaire was sent to all board-certified gastroenterologists in Switzerland to specifically address their strategy to monitor IBD between May 2009 and April 2010. RESULTS: The response rate was 57% (153/270). Fifty-two percent of gastroenterologists worked in private practice and 48% worked in hospitals. Seventy-eight percent judged clinical activity to be the most relevant criterion for monitoring IBD activity, 15% chose endoscopic severity, and 7% chose biomarkers. Seventy percent of gastroenterologists based their therapeutic decisions on clinical activity, 24% on endoscopic severity, and 6% on biomarkers. The following biomarkers were used for IBD activity monitoring: CRP, 94%; differential blood count, 78%; fecal calprotectin (FC), 74%; iron status, 63%; blood sedimentation rate, 3%; protein electrophoresis, 0.7%; fecal neutrophils, 0.7%; and vitamin B12, 0.7%. Gastroenterologists in hospitals and those with ≤ 10 years of professional experience used FC more frequently compared with colleagues in private practice (P=0.035) and those with > 10 years of experience (P<0.001). CONCLUSIONS: Clinical activity is judged to be more relevant for monitoring IBD activity and guiding therapeutic decisions than endoscopic severity and biomarkers. As such, the accumulating scientific evidence on the clinical impact of mucosal healing does not yet seem to influence the management of IBD in daily gastroenterologic practice.

Marqueurs diagnostiques de la carence en fer: lequel choisir [Diagnostic markers of iron deficiency: which should we choose?].

Iron deficiency is generally investigated when faced with anemia, or with symptoms that could be related to iron deficiency without anemia. This simple disorder is easy to treat, provided that the diagnosis is correct. Several biological tests are available, but their interpretation is oftentimes problematic. Pre-analytical factors can interfere with measurements, normal values can change depending on suppliers, and, above all, results from different markers can be contradictory in some clinical situations. The aim of this article is to evaluate how the evolution of scientific knowledge and clinical trials can contribute to a better understanding and greater reliability in the diagnosis of iron deficiency.

Estudo eritroleucométrico e proteinograma sérico do sangue do cordão umbilical e jugular de eqüinos ao nascimento e de suas respectivas mães

Colheram-se amostras de sangue do cordão umbilical (SCU) e do sangue circulante de cinco eqüinos neonatos, imediatamente após o nascimento, e o sangue da própria mãe, utilizando-se um sistema a vácuo. O material foi submetido à contagem global de hemácias e leucócitos e à determinação do volume globular e da concentração de hemoglobina; à contagem diferencial de leucócitos em esfregaços sangüíneos; e ao cálculo dos índices eritrocitométricos. Foram realizadas a dosagem de proteínas séricas totais e a eletroforese das proteínas séricas em gel de agarose. Não houve diferenças significativas entre os parâmetros do SCU e do sangue da jugular dos potros. No SCU dos potros observaram-se valores mais elevados para contagem global de hemácias (9,75x10(6)/µl), dosagem de hemoglobina (14,65g/dl) e concentração de hemoglobina corpuscular média (37,23g/dl); e valores menores para volume corpuscular médio (40,50fl), proteína total (4,37g/dl), alfa-globulinas (0,65g/dl), beta-globulinas (1,10g/dl), gama-globulinas (0g/dl) e contagens global (5,40 x 10³/µl) e diferencial de leucócitos, exceto contagem de neutrófilos bastonetes e monócitos, quando comparados com os valores obtidos no sangue de suas mães.

Efeito do sítio de venopunção nos parâmetros hematológicos em tigre-d'água-americano, Trachemys scripta elegans

O objetivo do presente estudo foi realizar a comparação entre dois sítios de coleta sanguínea em 24 exemplares de tigre-d'água-americano (Trachemys scripta elegans) oriundos de um criadouro comercial, localizado no município de Antonina, litoral do Paraná, Brasil. Os animais foram submetidos a contenção física e as venopunções foram realizadas no seio supraocciptal e na veia coccígea dorsal. As amostras heparinizadas foram identificadas e refrigeradas para posterior análise laboratorial. A contagem total de eritrócitos e leucócitos foi realizada pela técnica de hemocitometria. O hematócrito (Ht) e a hemoglobina (Hb) foram determinados pelo método de microhematócrito e cianometahemoglobina, respectivamente. A proteína plasmática total (PPT) foi determinada por refratometria e a contagem diferencial de leucócitos foi realizada através da técnica de Shilling. Houve diferença significativa no número de leucócitos e no valor da proteína plasmática total, e em ambos os casos os valores encontrados nas amostras provenientes da veia coccígea dorsal foram inferiores. A diferença encontrada no número de leucócitos provavelmente foi devido à contaminação por linfa, que também justifica o menor valor na concentração da proteína plasmática total. Conclui-se que é mais indicada a venopunção no seio supraocciptal quando comparado a veia coccígea dorsal.