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1.
J Insect Sci ; 22(3)2022 May 01.
Article de Anglais | MEDLINE | ID: mdl-35596588

RÉSUMÉ

The expansion of Integrated Pest Management (IPM), including biological control, has had several positive consequences for the agricultural environment and participants in the production chain. To enable successful operation and applications of biological control, production of insects used for rearing natural enemies (parasitoids and predators) must be optimized to reduce time and costs and improve production both qualitatively and quantitatively. The present study evaluated the effect of wheat varieties, the main component of artificial diets for Ephestia kuehniella, on the reproductive performance and biological parameters of this flour moth, which is used for mass production of Trichogramma spp. (Hymenoptera: Trichogrammatidae) and other parasitoids and predators. Four varieties of wheat were compared: BRS 327, BRS Marcante, BRS Parrudo, and KBR, with and without the addition of corn E. kuehniella reared on 97% BRS 327 wheat flour + 3% nutritional yeast had the best biological parameters and substitution of corn for about half of the wheat increased the number of eggs per female.


Sujet(s)
Hymenoptera , Papillons de nuit , Animaux , Régime alimentaire , Femelle , Farine , Humains , Ovule , Triticum , Zea mays
2.
Iran J Vet Res ; 21(2): 92-96, 2020.
Article de Anglais | MEDLINE | ID: mdl-32849886

RÉSUMÉ

BACKGROUND: Analgesic and hemodynamic effects of ketamine in subanesthetic doses during surgical anesthesia and postoperative, are due to the action on the N-methyl-D-aspartate receptors (NMDAR). AIMS: To evaluate the intraoperative cardiorespiratory effects provided by ketamine compared to lidocaine, both administered epidurally, in bitches submitted to ovariohysterectomy. METHODS: Thirty-six dogs of different breeds were used in a randomized, prospective, and blinded clinical trial. Two groups were formed: GKET (ketamine 3 mg/kg, n=18) and GLIDO (lidocaine 4 mg/kg, n=18). Animals were premedicated with acepromazine 0.05 mg/kg intravenous. Anesthesia was induced with propofol 5 mg/kg intravenous. Anesthetic maintenance was performed with isoflurane in 100% oxygen. Every 5 min during surgery, heart rate (HR), respiratory rate (RR), esophageal temperature (°C), oxygen saturation (SPO2), end tidal carbon dioxide (ETCO2) and mean arterial pressure (MAP) were monitored. RESULTS: Cardiorespiratory variables during anesthesia were within normal ranges. Heart rate was significantly higher at 5 (108 ± 12 vs 95 ± 11) and 10 (110 ± 11 vs 97 ± 11) min in GKET compared to GLIDO after the start of surgery (P=0.03 and P=0.01, respectively). Mean arterial pressure was higher in GKET, (100 ± 23, 105 ± 35, and 103 ± 35 mmHg) in comparison with GLIDO (66 ± 7, 74 ± 10, and 67 ± 9 mmHg) at 20, 25 and 30 min (P=0.01, P=0.004, and P=0.002, respectively). Mild hypothermia at 25 (36.5 1.3C) and 30 (36.5 1.4C) min in the GKET was recorded. CONCLUSION: Epidural administration of ketamine provides better hemodynamic stability, compared to the use of epidural lidocaine.

3.
Neotrop Entomol ; 49(2): 250-257, 2020 Apr.
Article de Anglais | MEDLINE | ID: mdl-31797306

RÉSUMÉ

Huanglongbing (HLB), the most destructive citrus disease worldwide, was first recorded in Brazil in 2004, and since then, more than 50 million trees identified with this disease have been eliminated. The disease is managed mainly by controlling the psyllid vector Diaphorina citri Kuwayama, 1908 (Hemiptera: Liviidae). Although the presence of the insect in commercial citrus groves is low, HLB infection rates increase in areas bordering the groves. The disease is transmitted by psyllids from host citrus plants in areas outside the managed groves, such as abandoned or organic groves and residential trees, and from orange jasmine plants in urban settings. In order to provide information to support HLB control, this study evaluated the biotic and abiotic variables that affect the dynamics of D. citri populations after releases of the parasitoid wasp Tamarixia radiata (Waterston, 1922) (Hymenoptera: Eulophidae) in external sources of HLB inocula. The study was divided into two parts. After releasing the parasitoids in non-commercial areas, we determined the following: (a) the variables that significantly affected the number of nymphs collected on shoots in the same non-commercial area; (b) the variables that significantly affected the number of adult psyllids collected in a neighboring commercial citrus area. Our results indicated that the number of nymphs in external areas was affected only by the host plant and rainfall. However, periodic parasitoid releases significantly reduced the number of adult psyllids collected in the commercial area. The results indicate that the release of parasitoids in external sources of inocula has the potential to maximize actions for D. citri control, contributing to the reduction of psyllid populations in commercial areas. Consequently, this strategy may help to manage the disease infection without an increase in insecticide use.


Sujet(s)
Hemiptera/parasitologie , Lutte biologique contre les nuisibles , Guêpes/physiologie , Animaux , Brésil , Citrus , Hemiptera/microbiologie , Maladies des plantes/microbiologie
4.
Rev Gastroenterol Mex (Engl Ed) ; 84(4): 427-433, 2019.
Article de Anglais, Espagnol | MEDLINE | ID: mdl-30292584

RÉSUMÉ

INTRODUCTION AND OBJECTIVE: Eosinophilic esophagitis is a chronic, immune-mediated disease described in case series and publications worldwide. Over the past twenty years, the authors of different studies have attempted to evaluate its incidence and prevalence. The objetive of the present study was to estimate the prevalence of eosinophilic esophagitis in a group of children seen at 36 pediatric gastroenterology centers in ten Latin American countries. MATERIALS AND METHODS: A multicenter, observational, and cross-sectional study was conducted that estimated the period prevalence of eosinophilic esophagitis in children seen at outpatient consultation and that underwent diagnostic upper gastrointestinal endoscopy for any indication at 36 centers in 10 Latin American countries, within a 3-month time frame. RESULTS: Between April and June 2016, 108 cases of eosinophilic esophagitis were evaluated. Likewise, an average of 29,253 outpatient consultations and 4,152 diagnostic upper gastrointestinal endoscopies were carried out at the 36 participating centers. The period prevalence of eosinophilic esophagitis in the population studied (n=29,253) was 3.69 cases×1,000 (95% CI: 3.04 to 4.44), and among the children that underwent routine upper gastrointestinal endoscopy (n=4,152), it was 26x1,000 (95% CI: 22.6 to 29.4). CONCLUSIONS: The general period prevalence of eosinophilic esophagitis in a group of children evaluated at 36 Latin American pediatric gastroenterology centers was 3.69×1,000, and in the children that underwent endoscopy, it was 26×1,000. There was important prevalence variability between the participating countries and centers. The present analysis is the first study conducted on the prevalence of pediatric eosinophilic esophagitis in Latin America.


Sujet(s)
Oesophagite à éosinophiles/épidémiologie , Adolescent , Enfant , Enfant d'âge préscolaire , Études transversales , Femelle , Gastroentérologie , Hôpitaux spécialisés , Humains , Nourrisson , Amérique latine/épidémiologie , Mâle , Prévalence
5.
J Econ Entomol ; 111(1): 120-126, 2018 02 09.
Article de Anglais | MEDLINE | ID: mdl-29267899

RÉSUMÉ

The fall armyworm, Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), cannot survive prolonged periods of freezing temperatures, thereby limiting where it can overwinter in North America. Climate change is anticipated to reduce the frequency of freeze days in Florida over the decades, with the potential consequence of a significant expansion of the overwintering range, whose northern limit in North America was assessed between 27 and 28°N in the last century. To assess this possibility, the development of the fall armyworm on corn leaves, one of the main host plants in the United States, was determined at five constant temperatures ranging from 14 to 30°C. Based on the development time, the thermal constant and the lower threshold temperature were used to estimate the number of generations of fall armyworm at 42 locations in the state of Florida, from 2006 to 2016. Maps were constructed to provide a visual description of the interpolated data, using GIS (Geographic Information System). The highest number of generations was observed in the counties farther south, an area that showed the highest temperatures during the years and plays a strategic role in maintaining fall armyworm populations in corn fields. Additionally, we conclude that in the absence of freeze periods, the northern limit for fall armyworm overwintering should be between 28 and 29°N.


Sujet(s)
Changement climatique , Chaine alimentaire , Spodoptera/croissance et développement , Zea mays , Animaux , Floride , Larve/croissance et développement , Saisons , Température , Zea mays/croissance et développement
6.
Environ Entomol ; 46(6): 1189-1194, 2017 12 08.
Article de Anglais | MEDLINE | ID: mdl-29029089

RÉSUMÉ

Fruit flies are among the most damaging insect pests of commercial fruit in Brazil. It is important to understand the landscape elements that may favor these flies. In the present study, spatial data from surveys of species of Anastrepha Schiner (Diptera: Tephritidae) in an urban area with forest fragments were analyzed, using geostatistics and Geographic Information System (GIS) to map the diversity of insects and evaluate how the forest fragments drive the spatial patterns. The results indicated a high diversity of species associated with large fragments, and a trend toward lower diversity in the more urbanized area, as the fragment sizes decreased. We concluded that the diversity of Anastrepha species is directly and positively related to large and continuous forest fragments in urbanized areas, and that combining geostatistics and GIS is a promising method for use in insect-pest management and sampling involving fruit flies.


Sujet(s)
Répartition des animaux , Biote , Tephritidae/physiologie , Animaux , Brésil , Villes , Écosystème , Femelle , Forêts , Systèmes d'information géographique , Mâle , Analyse spatiale
7.
Mater Sci Eng C Mater Biol Appl ; 79: 30-36, 2017 Oct 01.
Article de Anglais | MEDLINE | ID: mdl-28629022

RÉSUMÉ

Carbon nanotubes (CNT) can be chemically modified by doping or functionalization to change the chemical and surface properties. These characteristic makes to CNT candidates for multiple applications including medical field in cardiovascular area. A novel method to CNT functionalization by formation of two compounds: α-bromoacid and the organic compound 2-(methacryloyloxy) ethyl phosphorylcholine (MPC), will be discussed in this article. According to results, CNT are suggested like candidates to repel oxidized low-density lipoproteins (ox-LDL) to prevent restenosis. The electronegative character on surface of functionalized CNT (F-CNT) is shown by wettability analysis observing a repellent behaviour in contact with ox-LDL after functionalization route. Here we analyse the toxicity of CNT and F-CNT on HepG2 cell line and find no damage to the cell membrane of HepG2 cells in concentration at doses below 1mg/ml.


Sujet(s)
Nanotubes de carbone , Lipoprotéines LDL , Endoprothèses , Propriétés de surface , Mouillabilité
8.
Neotrop Entomol ; 46(3): 283-288, 2017 Jun.
Article de Anglais | MEDLINE | ID: mdl-27943025

RÉSUMÉ

Studies of the influence of biological parameters on the spatial distribution of lepidopteran insects can provide useful information for managing agricultural pests, since the larvae of many species cause serious impacts on crops. Computational models to simulate the spatial dynamics of insect populations are increasingly used, because of their efficiency in representing insect movement. In this study, we used a cellular automata model to explore different patterns of population distribution of Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), when the values of two biological parameters that are able to influence the spatial pattern (larval viability and adult longevity) are varied. We mapped the spatial patterns observed as the parameters varied. Additionally, by using population data for S. frugiperda obtained in different hosts under laboratory conditions, we were able to describe the expected spatial patterns occurring in corn, cotton, millet, and soybean crops based on the parameters varied. The results are discussed from the perspective of insect ecology and pest management. We concluded that computational approaches can be important tools to study the relationship between the biological parameters and spatial distributions of lepidopteran insect pests.


Sujet(s)
Produits agricoles , Spodoptera , Répartition des animaux , Animaux , Larve , Longévité , Glycine max , Zea mays
9.
Behav Brain Res ; 310: 59-67, 2016 09 01.
Article de Anglais | MEDLINE | ID: mdl-27173433

RÉSUMÉ

Anxiety and depression in diabetic patients contributes to a poor prognosis, but possible causal relationships have been controversial. Anxiety, fear, and anhedonia are mediated by interactions between different deep structures of the temporal lobe (e.g., amygdala complex and hippocampus) and other forebrain-related structures (e.g., lateral septal nucleus). Connections between these structures and the hypothalamic orexinergic system are necessary for the maintenance of energy and wakefulness. However, few studies have explored the impact of long-term hyperglycemia in these structures on anxiety. We induced long-term hyperglycemia (glucose levels of ∼500mg/dl) in Wistar rats by injecting them with alloxan and simultaneously protecting them from hyperglycemia by injecting them daily with a low dose of insulin (i.e., just enough insulin to avoid death), thus maintaining hyperglycemia and ketonuria for as long as 6 weeks. Compared with controls, long-term hyperglycemic rats exhibited a significant reduction of Fos expression in the lateral septal nucleus and basolateral amygdala, but no differences were found in cerebellar regions. Orexin-A cells appeared to be inactive in the lateral hypothalamus. No differences were found in sucrose consumption or behavior in the elevated plus maze compared with the control group, but a decrease in general locomotion was observed. These data indicate a generalized blunting of the metabolic brain response, accompanied by a decrease in locomotion but no changes in hedonic- or anxiety-like behavior.


Sujet(s)
Amygdale (système limbique)/métabolisme , Hyperglycémie/métabolisme , Hypothalamus/métabolisme , Septum du cerveau/métabolisme , Alloxane , Amygdale (système limbique)/anatomopathologie , Anhédonie , Animaux , Anxiété , Maladie chronique , Saccharose alimentaire , Modèles animaux de maladie humaine , Hyperglycémie/anatomopathologie , Hyperglycémie/psychologie , Hypothalamus/anatomopathologie , Immunohistochimie , Cétose/métabolisme , Cétose/anatomopathologie , Cétose/psychologie , Mâle , Activité motrice/physiologie , Orexines/métabolisme , Protéines proto-oncogènes c-fos/métabolisme , Rat Wistar , Septum du cerveau/anatomopathologie
10.
Pflugers Arch ; 442(3): 376-82, 2001 Jun.
Article de Anglais | MEDLINE | ID: mdl-11484768

RÉSUMÉ

Carbachol-induced contractions of rat stomach fundus strips, obtained in a nutrient solution containing 1.8 mM Ca2+, were resistant to Ca2+ withdrawal, even after 1 h of bathing the tissues in a nominal 0 Ca2+ solution. This was not observed when K+ was used to evoke contractions, which were rapidly inhibited after Ca2+ removal (t1/2=2 min). The effect of carbachol in 0 Ca2+ solution was reduced by using drugs that reduce intracellular pools of Ca2+, such as caffeine (1-3 mM), ryanodine (30 microM) or thapsigargin (1 microM), corroborating the involvement of intracellular Ca2+ stores. On the other hand, when the 0 Ca2+ solution contained EGTA, a complete decline of carbachol effects was observed within about 8 min, indicating the involvement of extracellular Ca2+. Atomic absorption spectrometry showed that our 0 Ca2+ solution still contained 45 microM Ca2+, which was drastically reduced to 5.9 nM in the presence of EGTA. Taken together, our results indicate that the effects of carbachol are due to the mobilization of caffeine-, ryanodine- and thapsigargin-sensitive intracellular Ca2+ stores, and that these stores are not inactivated or depleted if micromolar concentrations (45 microM), but not nanomolar concentrations (5.9 nM) of Ca2+ are maintained in the extracellular milieu.


Sujet(s)
Calcium/métabolisme , Fundus gastrique/physiologie , Récepteur muscarinique/métabolisme , Animaux , Transport biologique/effets des médicaments et des substances chimiques , Caféine/pharmacologie , Calcium/pharmacologie , Carbachol/pharmacologie , Chélateurs/pharmacologie , Agonistes cholinergiques/pharmacologie , Acide egtazique/pharmacologie , Antienzymes/pharmacologie , Femelle , Muscles lisses/physiologie , Nickel/pharmacologie , Péristaltisme/effets des médicaments et des substances chimiques , Inhibiteurs de la phosphodiestérase/pharmacologie , Rats , Rats de lignée WF , Ryanodine/pharmacologie , Thapsigargine/pharmacologie
11.
Invest Clin ; 42(2): 131-46, 2001 Jun.
Article de Espagnol | MEDLINE | ID: mdl-11416979

RÉSUMÉ

A study, under laboratory and field conditions, was conducted to evaluate the effectiveness, persistence in the time and some factors that can affect the larvicidal action of the Griselef formulation of the sporogenous bacteria Bacillus sphaericus strain 2362, on the larvae population of the Anopheles nuñeztovari Gabaldón, the main malaria vector in western Venezuela. The degree of susceptibility of this species to the Bacillus sphaericus was determined to be at a LD50 in 0.07 ppm a LD95 in 0.69 ppm. The pH ranges of the water, as tested in the laboratory, showed that values between 7.0 and 9.0 did not affect the action of the larvicide, producing more than 95% of mortality after 72 hours of observation. Under controlled field conditions, the high susceptibility of the An. nuñeztovari larvae to the larvicidal action of the product was demonstrated. With a dose of 5 ml/m2, a 100% mortality was obtained after 72 hours of exposure. In the field, it was determined that after 12 hours, solar radiation decreased the effectiveness of the B. sphaericus in 30% and that the presence of vegetation reduced the biolarvicidal effect between 5 and 12%. Under natural field conditions, it was shown that the larvicide was effective, since a 100% larval mortality was obtained in the two treated breeding places. This effect persisted up to 4 months of observation, with more than 85% of larvae reduction, showing that it is capable or remaining in the natural environment.


Sujet(s)
Anopheles , Bacillus , Lutte biologique contre les nuisibles/méthodes , Animaux , Anopheles/classification , Larve , Venezuela
12.
Eur J Pharmacol ; 417(1-2): 99-109, 2001 Apr 06.
Article de Anglais | MEDLINE | ID: mdl-11301064

RÉSUMÉ

The blockade of exocytosis induced by the putative endogenous ligand for imidazoline receptors, agmatine, was studied by using on-line measurement of catecholamine release in bovine adrenal medullary chromaffin cells. Agmatine inhibited the acetylcholine-evoked release of catecholamines in a concentration-dependent manner (IC(50)=366 microM); the K(+)-evoked release of catecholamines was unaffected. Clonidine (100 microM) and moxonidine (100 microM) also inhibited by 75% and 50%, respectively, the acetylcholine-evoked response. In cells voltage-clamped at -80 mV, the intermittent application of acetylcholine pulses elicited whole-cell inward currents (I(ACh)) that were blocked 63% by 1 mM agmatine. The onset of blockade was very fast (tau(on) = 31 ms); the recovery of the current after washout of agmatine also occurred very rapidly (tau(off = 39 ms). Efaroxan (10 microM) did not affect the inhibition of I(ACh) elicited by 1 mM agmatine. I(ACh) was blocked 90% by 100 microM clonidine and 50% by 100 microM moxonidine. The concentration-response curve for acetylcholine to elicit inward currents was shifted to the right in a non-parallel manner by 300 microM agmatine. The blockade of I(ACh) caused by agmatine (100 microM) was similar at various holding potentials, around 50%. When intracellularly applied, agmatine did not block I(ACh). At 1 mM, agmatine blocked I(Na) by 23%, I(Ba) by 14%, I(K(Ca)) by 16%, and I(K(VD)) by 18%. In conclusion, agmatine blocks exocytosis in chromaffin cells by blocking nicotinic acetylcholine receptor currents. In contrast to previous views, these effects seem to be unrelated to imidazoline receptors.


Sujet(s)
Agmatine/pharmacologie , Catécholamines/métabolisme , Cellules chromaffines/effets des médicaments et des substances chimiques , Récepteurs des médicaments/physiologie , Acétylcholine/pharmacologie , Agmatine/métabolisme , Animaux , Benzofuranes/pharmacologie , Sites de fixation , Fixation compétitive , Canaux calciques/effets des médicaments et des substances chimiques , Canaux calciques/physiologie , Bovins , Cellules cultivées , Cellules chromaffines/métabolisme , Cellules chromaffines/physiologie , Clonidine/pharmacologie , Relation dose-effet des médicaments , Stimulation électrique , Imidazoles/pharmacologie , Récepteurs des imidazolines , Potentiels de membrane/effets des médicaments et des substances chimiques , Potassium/pharmacologie , Canaux potassiques/effets des médicaments et des substances chimiques , Canaux potassiques/physiologie , Récepteurs nicotiniques/effets des médicaments et des substances chimiques , Récepteurs nicotiniques/métabolisme , Récepteurs nicotiniques/physiologie , Canaux sodiques/effets des médicaments et des substances chimiques , Canaux sodiques/physiologie
13.
Rev Inst Med Trop Sao Paulo ; 40(3): 145-50, 1998.
Article de Anglais | MEDLINE | ID: mdl-9830727

RÉSUMÉ

In view of the scarce references concerning the histological data in congenital parvovirus human B19 infection, we intend to provide a description of the pathological features observed in six autopsies. The virus was detected by DNA hybridization (ISH-DBH), PCR and electronmicroscopy (EM) in paraffin-embedded feto-placentary tissues. These cases constitute a subset from 86 Non Immunologic Hydrops Fetalis (NIHF) cases, in which a systemic complex of inflammatory/degenerative lesions of unknown etiology was visualized by optical microscopy. In one case a syphilitic process was detected, typefying a double infection. All fetuses showed a similar pathology--hydrops, hepato-splenomegaly, lung hypoplasia and erythroblastemia, the specific histological feature being the presence of intranuclear inclusions in the erythroid progenitors, in the erythropoietic visceral tissue and in blood marrow. Complex cardiopathy allied to abnormal lung lobulation and polisplenia were observed once; in 2 cases endocardial fibroelastosis was diagnosed. The pulmonary lesions were represented by dysmaturity allied to interstitial mononuclear infiltration. The hepatic consisted of cholestasis, portal fibrosis, canalicular proliferation, hemossiderosis, focal necroses and giant cell transformation. The central nervous system lesions were predominantly anoxic although the autolysis impaired a correct diagnosis.


Sujet(s)
Anasarque foetoplacentaire/anatomopathologie , Infections à Parvoviridae/anatomopathologie , Infections à Parvoviridae/virologie , Parvovirus humain B19 , Complications infectieuses de la grossesse/anatomopathologie , Complications infectieuses de la grossesse/virologie , Inclusions érythrocytaires/ultrastructure , Femelle , Humains , Anasarque foetoplacentaire/virologie , Mâle , Parvovirus/isolement et purification , Grossesse , Études rétrospectives
14.
Am J Physiol ; 274(6): C1745-54, 1998 06.
Article de Anglais | MEDLINE | ID: mdl-9611141

RÉSUMÉ

Toxin-gamma (Tgamma) from the Brazilian scorpion Tityus serrulatus venom caused a concentration- and time-dependent increase in the release of norepinephrine and epinephrine from bovine adrenal medullary chromaffin cells. Tgamma was approximately 200-fold more potent than veratridine judged from EC50 values, although the maximal secretory efficacy of veratridine was 10-fold greater than that of Tgamma (1.2 vs. 12 microg/ml of catecholamine release). The combination of both toxins produced a synergistic effect that was particularly drastic at 5 mM extracellular Ca2+ concentration ([Ca2+]o), when 30 microM veratridine plus 0.45 microM Tgamma were used. Tgamma (0.45 microM) doubled the basal uptake of 45Ca2+, whereas veratridine (100 microM) tripled it. Again, a drastic synergism in enhancing Ca2+ entry was seen when Tgamma and veratridine were combined; this was particularly pronounced at 5 mM [Ca2+]o. Veratridine induced oscillations of cytosolic Ca2+ concentration ([Ca2+]i) in single fura 2-loaded cells without elevation of basal levels. In contrast, Tgamma elevated basal [Ca2+]i levels, causing only small oscillations. When added together, Tgamma and veratridine elevated the basal levels of [Ca2+]i without causing large oscillations. Tgamma shifted the current-voltage (I-V) curve for Na+ channel current to the left. The combination of Tgamma with veratridine increased the shift of the I-V curve to the left, resulting in a greater recruitment of Na+ channels at more hyperpolarizing potentials. This led to enhanced and more rapid accumulation of Na+ in the cell, causing cell depolarization, the opening of voltage-dependent Ca2+ channels, and Ca2+ entry and secretion.


Sujet(s)
Médulla surrénale/physiologie , Système chromaffine/physiologie , Neurotoxines/pharmacologie , Venins de scorpion/pharmacologie , Vératridine/pharmacologie , Médulla surrénale/effets des médicaments et des substances chimiques , Animaux , Calcium/métabolisme , Calcium/pharmacologie , Inhibiteurs des canaux calciques/pharmacologie , Canaux calciques/physiologie , Radio-isotopes du calcium , Bovins , Système chromaffine/effets des médicaments et des substances chimiques , Synergie des médicaments , Conductivité électrique , Cinétique , Norépinéphrine/métabolisme , Canaux sodiques/physiologie
16.
Mem Inst Oswaldo Cruz ; 91(2): 147-51, 1996.
Article de Anglais | MEDLINE | ID: mdl-8736082

RÉSUMÉ

Formalin-fixed paraffin embedded lung and liver tissue from 23 cases of non immune hydrops fetalis and five control cases, in which hydrops were due to syphilis (3) and genetic causes (2), were examined for the presence of human parvovirus B19 by DNA hybridisation. Using in situ hybridisation with a biotynilated probe one positive case was detected. Using 32P-labelled probes in a dot blot assay format, five further positives were obtained. These were all confirmed as positive by a nested polymerase chain reaction assay. Electron microscopy revealed virus in all these five positive cases. The six B19 DNA positive cases of hydrops fetalis were from 1974, 1980, 1982, 1987 and 1988, four of which occurred during the second half of the year, confirming the seasonality of the disease.


Sujet(s)
Foetus/virologie , Anasarque foetoplacentaire/virologie , Parvovirus humain B19/isolement et purification , Brésil , Humains
17.
Pediatr Pathol ; 14(5): 781-6, 1994.
Article de Anglais | MEDLINE | ID: mdl-7808976

RÉSUMÉ

We present an unusual case of extralobar pulmonary sequestration associated with hyaline membrane disease (HMD) that caused the death of a premature baby in the first day of life. The sequestered parenchyma was nourished by an aberrant aortic vessel. Notable was the presence of typical HMD in all the lung parenchyma perfused by the pulmonary artery; the sequestered lung tissue presented a dysplastic structure compatible with CCAM. A few similar cases have been found in the literature. In all of the reported cases there are morphologic aspects characteristic of HMD in the portions normally receiving blood from the pulmonary artery. These findings suggest the importance of the blood pulmonary circulation in the pathogenesis of HMD, whose exact causes are not fully known.


Sujet(s)
Séquestration bronchopulmonaire/anatomopathologie , Maladie des membranes hyalines/complications , Séquestration bronchopulmonaire/complications , Issue fatale , Femelle , Humains , Maladie des membranes hyalines/anatomopathologie , Nouveau-né
18.
Mem. Inst. Oswaldo Cruz ; 88(1): 141-7, jan.-mar. 1993. tab, ilus
Article de Anglais | LILACS | ID: lil-117663

RÉSUMÉ

Pulmonary lesions compatible with adenovirus infection were detected by gross and microscopic examination of autopsy tissues children aged from 5 to 34 months. Hepatic lesions indicative of systemic infection were also found in four of the chisldren. The viral etiology was confirmed in three cases by in-situ hibridization, electro-microscopy and immunofluorescence performed in parafin-embedded tissues, and in one case by cell culture isolation of adenovirus type 2 from nasopharyngeal exudate. Routine testing by methods additional to conventional light microscopy would probably have revealed a larger number of adenovirus infections among the 1.103 autopsy records analyzed in this study


Sujet(s)
Enfant , Humains , Infections à Adenoviridae , Infections humaines à adénovirus , Pneumopathie virale/étiologie
19.
Mem Inst Oswaldo Cruz ; 88(1): 141-7, 1993.
Article de Anglais | MEDLINE | ID: mdl-8246749

RÉSUMÉ

Pulmonary lesions compatible with adenovirus infection were detected by gross and microscopic examination of autopsy tissues from children aged from 5 to 34 months. Hepatic lesions indicative of systemic infection were also found in four of the children. The viral etiology was confirmed in three cases by in-situ hybridization, electron-microscopy and immunofluorescence performed in paraffin-embedded tissues, and in one case by cell culture isolation of adenovirus type 2 from nasopharyngeal exudate. Routine testing by methods additional to conventional light microscopy would probably have revealed a larger number of adenovirus infections among the 1,103 autopsy records analyzed in this study.


Sujet(s)
Infections humaines à adénovirus/anatomopathologie , Pneumopathie virale/anatomopathologie , Adénovirus humains/ultrastructure , Enfant d'âge préscolaire , Humains , Nourrisson , Foie/microbiologie , Foie/ultrastructure , Pneumopathie virale/microbiologie
20.
Br J Pharmacol ; 107(2): 610-5, 1992 Oct.
Article de Anglais | MEDLINE | ID: mdl-1422602

RÉSUMÉ

1. The rat vas deferens was excised, stored at 4-6 degrees C and tested after 24, 48, 72 or 96 h for its contractile activity and for the presence of innervation. 2. The maximal contractile capacity of the vas, tested through cumulative concentrations of barium chloride (3 x 10(-2) M) was progressively reduced from about 110 mm to about 63 mm after 72 h, without further decay after 96 h. Spontaneous rhythmic contractions were practically absent. 3. A loss of endogenous pools of catecholamines was indicated by four parameters: (a) a decline of about 80% after 24 h and of more than 95% after 48 h of the contractile effect of the indirect sympathomimetic agonist tyramine; (b) a fall of about 20%, 50% and 85% on the concentration of noradrenaline, respectively after 24, 48 and 72 h; (c) a fall of about 25% and 90% after respectively 24 and 48 h, of the activity of dopamine-beta-hydroxylase (DBH); (d) a decline of noradrenaline-induced histofluorescence on cross sections of the vas. 4. A loss of neuronal uptake capacity was indicated by: (a) a progressive variation of the apparent affinity for adrenaline, expressed as pD2 values, that increased by about 1.5 log units (corresponding to a 30 fold potentiation) after 72 h, and (b) a reduction of the ability of cocaine to potentiate the contractile effects of adrenaline. 5. The pD2 values for barium chloride, 5-hydroxytryptamine (5-HT) and histamine were not significantly changed, while the corresponding value for acetylcholine was slightly but significantly reduced by about 0.8 log units. 6. The maximal heights of concentration-response curves for noradrenaline, acetylcholine, histamine and 5-HT were reduced by 42-66% in relation to controls. However, when this reduction was measured in relation to the corresponding barium effect, by means of the relative responsiveness ratio (p), a small though significant increase was observed for noradrenaline, and a fall for the other drugs.7. It is concluded that: (1) the values for the various biochemical and pharmacological parameters decline at different rates, though revealing altogether that denervation is completed by at least 85% after 72 h of hypothermic storage; (2) two of the results, i.e., the lack of spontaneous rhythmic contractions and the lack of increased contractile effects for acetylcholine, 5-HT and histamine, indicate that in these conditions the vas is devoid of the so-called nonspecific signs of denervation.


Sujet(s)
Composés du baryum , Chlorures , Basse température , Conduit déférent/innervation , Acétylcholine/pharmacologie , Animaux , Baryum/pharmacologie , Catécholamines/métabolisme , Dénervation , Épinéphrine/métabolisme , Épinéphrine/pharmacologie , Histamine/pharmacologie , Techniques in vitro , Mâle , Contraction musculaire , Muscles lisses/physiologie , Norépinéphrine/pharmacologie , Rats , Rat Wistar , Sérotonine/pharmacologie , Tyramine/pharmacologie , Conduit déférent/métabolisme , Conduit déférent/physiologie
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