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1.
Neotrop Entomol ; 38(3): 395-404, 2009.
Article in Portuguese | MEDLINE | ID: mdl-19618058

ABSTRACT

The goal of this work was to evaluate the effects of the pesticides abamectin, carbaryl, fenitrothion, methidathion, sulphur and trichlorfon on eggs of two Chrysoperla externa (Hagen) populations, as well as on the subsequent developmental stages and reproduction capacity of this green lacewing. Pesticide exposure and distilled water (control) were accomplished using a Potter's tower. None of the evaluated pesticides affected the egg viability of the C. externa populations studied, but abamectin and carbaryl caused significant mortality of other developmental stages of the predator. Sex ratio and reproduction capacity of females originated from treated eggs were unaffected. However, egg viability of C. externa from Bento Gonçalves, RS, Brazil, was reduced by sulphur. Considering to the total effect (E) of each pesticide, trichlorfon, fenitrothion, methidathion and abamectin were harmless to both C. externa populations (Bento Gonçalves and Vacaria), when applied on eggs, whereas carbaryl was slightly harmful. On the other hand, the fungicide sulphur was slightly harmful to C. externa from Bento Gonçalves, but harmless to those from Vacaria.


Subject(s)
Insect Control , Insecta , Malus , Pesticides/toxicity , Animals , Malus/parasitology , Ovum/drug effects , Time Factors
2.
Neotrop. entomol ; 38(3): 395-404, May-June 2009. graf, tab
Article in Portuguese | LILACS | ID: lil-519361

ABSTRACT

Os efeitos dos pesticidas abamectim, carbaril, fenitrotiom, metidatiom, enxofre e triclorfom foram avaliados sobre a fase de ovo de duas populações de Chrysoperla externa (Hagen), bem como sobre as fases subsequentes do desenvolvimento e reprodução do predador. A pulverização dos pesticidas e de água destilada (testemunha) sobre ovos de C. externa foi realizada por meio de torre de Potter. Nenhum dos pesticidas avaliados reduziu a viabilidade de ovos tratados, independente da população de C. externa estudada. Para as demais fases de desenvolvimento, apenas carbaril causou mortalidade acumulada significativa de ambas as populações quando em comparação aos demais pesticidas. A razão sexual dos adultos obtidos não foi afetada por nenhum dos compostos. Nenhum dos pesticidas afetou negativamente a capacidade de oviposição de fêmeas de C. externa oriundas de ovos tratados. No entanto, enxofre reduziu a viabilidade de ovos depositados por fêmeas da população de Bento Gonçalves. Considerando-se o efeito total (E) de cada pesticida, triclorfom, fenitrotiom, metidatiom e abamectim foram inócuos a ambas as populações de C. externa quando aplicados sobre seus ovos, enquanto carbaril foi considerado levemente prejudicial; o fungicida enxofre, por outro lado, foi considerado levemente prejudicial à população de Bento Gonçalves, e inócuo aos insetos da população de Vacaria.


The goal of this work was to evaluate the effects of the pesticides abamectin, carbaryl, fenitrothion, methidathion, sulphur and trichlorfon on eggs of two Chrysoperla externa (Hagen) populations, as well as on the subsequent developmental stages and reproduction capacity of this green lacewing. Pesticide exposure and distilled water (control) were accomplished using a Potter's tower. None of the evaluated pesticides affected the egg viability of the C. externa populations studied, but abamectin and carbaryl caused significant mortality of other developmental stages of the predator. Sex ratio and reproduction capacity of females originated from treated eggs were unaffected. However, egg viability of C. externa from Bento Gonçalves, RS, Brazil, was reduced by sulphur. Considering to the total effect (E) of each pesticide, trichlorfon, fenitrothion, methidathion and abamectin were harmless to both C. externa populations (Bento Gonçalves and Vacaria), when applied on eggs, whereas carbaryl was slightly harmful. On the other hand, the fungicide sulphur was slightly harmful to C. externa from Bento Gonçalves, but harmless to those from Vacaria.


Subject(s)
Animals , Insect Control , Insecta , Malus , Pesticides/toxicity , Malus/parasitology , Ovum/drug effects , Time Factors
3.
Brain Res ; 876(1-2): 225-37, 2000 Sep 08.
Article in English | MEDLINE | ID: mdl-10973615

ABSTRACT

The hippocampus, one of the most studied regions of the mammalian forebrain, plays some well-established roles in topographic navigation. For two decades, one widely accepted explanation for the observed impairment of hippocampectomized rats in spatial navigation has been an inability to form place representations. In this report, we present a direct experimental evidence that animals with hippocampal lesions can learn to recognize places using the constellation of distinct landmarks. The extrahippocampal implementation of all three basic constituents of topographic orientation - guidance, vector navigation, and place recognition - shows that the hippocampus, and its place cells, serve a much more specialized cognitive function than previously thought. We propose that this function includes multi-place and multi-vector topographic integration.


Subject(s)
Hippocampus/physiology , Learning/physiology , Pattern Recognition, Visual/physiology , Space Perception/physiology , Animals , Cues , Male , Memory/physiology , Orientation/physiology , Rats , Rats, Long-Evans , Reference Values
4.
Naturwissenschaften ; 87(12): 532-4, 2000 Dec.
Article in English | MEDLINE | ID: mdl-11198192

ABSTRACT

Previous studies have explored two-dimensional path integration in rodents by recording responses to passive rotation on a horizontal plane. This study adds the element of passive rotation in a vertical plane, necessitating the mouse to integrate positional information from three dimensions. Mice were trained to climb a wire mesh joining two horizontal planes. The whole arena was rotated 90 degrees while the mouse was vertically oriented as it moved between planes. Rotation was conducted both clockwise and counter-clockwise, controls being provided by rotation of the arena while the mouse was in its nest-box. All 16 mice tested altered their direction of travel subsequent to rotation in the vertical plane, compensating with a change in their path on the following horizontal plane.


Subject(s)
Mice/physiology , Motor Activity/physiology , Rotation , Animals , Orientation
5.
Proc Natl Acad Sci U S A ; 96(24): 13845-6, 1999 Nov 23.
Article in English | MEDLINE | ID: mdl-10570160

ABSTRACT

Fall migratory monarch butterflies, tested for their directional responses to magnetic cues under three conditions, amagnetic, normal, and reversed magnetic fields, showed three distinct patterns. In the absence of a magnetic field, monarchs lacked directionality as a group. In the normal magnetic field, monarchs oriented to the southwest with a group pattern typical for migrants. When the horizontal component of the magnetic field was reversed, the butterflies oriented to the northeast. In contrast, nonmigratory monarchs lacked directionality in the normal magnetic field. The results are a direct demonstration of magnetic compass orientation in migratory insects.


Subject(s)
Butterflies/physiology , Animals , Behavior, Animal/physiology , Magnetics
6.
Opt Lett ; 24(11): 735-7, 1999 Jun 01.
Article in English | MEDLINE | ID: mdl-18073838

ABSTRACT

We show that solitarylike stimulated Raman excitations are possible in massive wavelength-division-multiplexed fiber-optic systems. These self-similar states can propagate across channels at a constant rate that depends on the total power launched in the system and the wave's spectral width. The evolution of these excitations under the action of noise and during collisions is investigated in detail.

7.
Behav Processes ; 41(3): 245-55, 1997 Dec.
Article in English | MEDLINE | ID: mdl-24896857

ABSTRACT

Mice (Mus musculus) that shuttle between their nest and an outside goal use different navigation mechanisms, depending on their distance from the nest. This was studied by rotating directional cues and the mice relative to one another. Close to home (20-50 cm) mice choose path integration and orientation by beacon, while farther away from the nest distal landmark orientation becomes more important. The larger the beacon is at the home site, the greater is the distance over which it is used as a directional cue. As mice head towards their nest, they demonstrate a tendency to home by means of distal landmarks at large distances, and by means of path integration or guided beacon integration at smaller distances. This space related sequence in the use of orientation mechanisms is the reverse from the temporal sequence (stages) of learning mechanisms employed when first learning to navigate home (Alyan and Jander, 1994).

8.
FEBS Lett ; 273(1-2): 168-72, 1990 Oct 29.
Article in English | MEDLINE | ID: mdl-2226849

ABSTRACT

We have isolated and sequenced a fragment of 469 amino acid residues from bovine type VIII collagen. The sequence was composed of a series of Gly-X-Y repeats which was interrupted 8 times by short imperfections. The number and relative location of these interruptions were similar to those of chicken alpha 1(X) and rabbit alpha 1(VIII) chain triple-helical domains. Comparison to published N-terminal sequences to two triple-helical fragments of bovine type VIII collagen and to the cDNA derived sequence of the rabbit alpha 1(VIII) chain showed that this fragment was the triple-helical domain of a second type VIII collagen chain which we designate alpha 2(VIII).


Subject(s)
Collagen/chemistry , Descemet Membrane/chemistry , Amino Acid Sequence , Animals , Cattle , Chromatography, Gel , Chromatography, High Pressure Liquid , Collagen/isolation & purification , Molecular Sequence Data , Peptide Fragments/isolation & purification , Protein Conformation , Sequence Homology, Nucleic Acid
9.
Eur J Biochem ; 189(3): 601-7, 1990 May 20.
Article in English | MEDLINE | ID: mdl-2351139

ABSTRACT

Type VIII collagen was isolated from bovine Descemet's membranes by pepsin treatment and salt fractionation, as described by Kapoor et al. [(1986) Biochemistry 25, 3930-3937]. Contaminating type IV collagen was removed by ion-exchange chromatography. Purified type VIII collagen consisted of two different polypeptide chains and, compared to the fiber forming collagens, showed a higher thermal stability. Corresponding fractions isolated from pepsinized human Ewing's sarcoma and fetal calf aorta reacted immunologically with a protein of similar molecular mass. After extraction of Descemet's membranes with guanidine hydrochloride, a peptide of about 60 kDa was obtained. This seems to be the tissue form of type VIII collagen.


Subject(s)
Collagen/isolation & purification , Amino Acids/analysis , Animals , Aorta/analysis , Aorta/embryology , Basement Membrane/analysis , Cattle , Chromatography, Ion Exchange , Collagen/ultrastructure , Cornea/analysis , Humans , Immunoblotting , Microscopy, Electron , Models, Molecular , Sarcoma, Ewing/analysis , Trypsin
10.
Cell Tissue Res ; 259(2): 305-12, 1990 Feb.
Article in English | MEDLINE | ID: mdl-2337925

ABSTRACT

The distribution of type-VI collagen in the human iris and ciliary body was investigated by means of immunohistochemical techniques and compared with that of type-IV collagen, fibronectin and laminin. As has been described for other tissues, type-VI collagen surrounds type-I and -III collagen fibers. The aggregated form of type-VI collagen (the "long-spacing" or "curly" collagen), which has already been described in the trabecular meshwork and sclera, was also observed at the ciliary muscle tips surrounding the anterior elastic tendons of this muscle. In addition, staining for type-VI collagen was seen directly adjacent to the basement membranes of the ciliary muscle cells, the iris muscles, the uveal vascular endothelia and nerves, but not adjacent to the epithelial basement membranes. The staining did not form a discrete line like the immunoreaction for type-IV collagen, but bundles of marked fibrils extended into the surrounding connective tissue. We assume that type-VI collagen similar to type-VII collagen forms part of an anchoring system for these tissues. As type-VII collagen has been described only in connection with epithelial basement membranes, both type-VI and type-VII collagens may represent anchoring fibrils, however for different tissue components.


Subject(s)
Ciliary Body/metabolism , Collagen/metabolism , Iris/metabolism , Aged , Aged, 80 and over , Ciliary Body/cytology , Humans , Immunohistochemistry , Iris/cytology
11.
Exp Eye Res ; 48(1): 139-47, 1989 Jan.
Article in English | MEDLINE | ID: mdl-2920781

ABSTRACT

Cross-strained fiber bundles called long-spacing collagen or curly collagen occur in normal eyes in the trabecular meshwork. It can be seen in the basement membrane of the trabecular lamellae, in the sheath of the elastic-like fibers and underneath the inner wall of Schlemm's canal, where it forms part of the so called plaque material. The amount of this long-spacing collagen increases with age and is significantly more pronounced in glaucomatous eyes. Using immunohistochemical and immuno-electronmicroscopic methods, we have been able to show that type VI collagen is present in the aggregates called long-spacing collagen.


Subject(s)
Collagen/analysis , Glaucoma/pathology , Trabecular Meshwork/ultrastructure , Age Factors , Aged , Aged, 80 and over , Basement Membrane/ultrastructure , Female , Humans , Laminin/analysis , Male , Middle Aged , Trabecular Meshwork/analysis
12.
Biochemistry ; 23(16): 3675-81, 1984 Jul 31.
Article in English | MEDLINE | ID: mdl-6433975

ABSTRACT

The 140 000-dalton collagenous glycoprotein (CGP) from calf aorta and ligament characterized by Gibson & Cleary (1982) [Gibson, M.A., & Cleary, E.G. (1982) Biochem. Biophys. Res. Commun. 105, 1288-1295] has been studied. In the electron microscope, rotary-shadowed CGP molecules appear similar to the dimers of type VI collagen (short-chain collagen, intima collagen) described by other authors [Furthmayr, H., Wiedemann, H., Timpl, R., Odermatt, E., & Engel, J. (1983) Biochem. J. 211, 303-311] except that they have larger globular domains. As shown by gel electrophoresis, pepsin treatment of CGP at 4 degrees C either before or after reduction releases polypeptide chains corresponding in size to those of type VI collagen. Electron microscopic examination shows that pepsin digestion of nonreduced CGP removes the outer globular domains, reduces the size of the inner ones, and separates the paired central strands. The residual structures look like type VI collagen dimers. When intact CGP is reduced, monomers with two large globular ends are obtained. Pepsin digestion of monomers removes most or all of both globular domains. In immunoblots, CGP and its pepsin-derived fragments react with antibodies directed against type VI collagen. The results indicate that type VI collagen is an integral component of CGP.


Subject(s)
Aorta/analysis , Collagen/isolation & purification , Glycoproteins/isolation & purification , Ligaments/analysis , Amino Acids/analysis , Animals , Antigen-Antibody Complex , Cattle , Microscopy, Electron , Molecular Weight , Pepsin A , Peptide Fragments/analysis
13.
Aktuelle Traumatol ; 14(2): 48-54, 1984 Apr.
Article in German | MEDLINE | ID: mdl-6144256

ABSTRACT

In case of pathologic fractures caused by metastases, operative stabilizing of the fractures is indicated if the general condition of the patient just permits an operation. It is the aim of treatment to reestablish the function of the extremity, to reduce pain and to give psychological support to the patient during his remaining life time. The operative procedure depends on the general conditions of the patient, the spreading and localisation of the metastases.


Subject(s)
Bone Neoplasms/complications , Fractures, Bone/surgery , Fractures, Closed/surgery , Adult , Aged , Bone Neoplasms/mortality , Bone Neoplasms/secondary , Female , Fractures, Closed/diagnostic imaging , Fractures, Closed/etiology , Germany, West , Humans , Male , Middle Aged , Neoplasms/pathology , Radiography
14.
Eur J Biochem ; 133(1): 39-46, 1983 Jun 01.
Article in English | MEDLINE | ID: mdl-6852033

ABSTRACT

Short-chain collagen was isolated from bovine and from human placenta after limited pepsin digestion. By reductive cleavage of disulfide bonds under non-denaturing conditions, mainly non-collagenous domains were cleaved off yielding a uniform component composed of three polypeptide chains with molecular masses between 37 kDa and 48 kDa in a nearly equimolar ratio. The chains (SC1*, SC2* and SC3*) were isolated and characterized. By comparison of peptide patterns obtained after various cleavage procedures, they could be identified as more or less shortened forms of SC1, SC2 and SC3, the isolation of which from bovine short-chain collagen has been described [Jander et al. (1981) Eur. J. Biochem. 114, 17-25]. The peptide patterns; as well as N-terminal sequence determination, give evidence for the genetic individuality of the three chains; the data so far available suggest that together they form one triple-helical structure which represents the collagenous domain of the basic molecular unit of short-chain collagen.


Subject(s)
Collagen/isolation & purification , Peptide Fragments/isolation & purification , Amino Acids/isolation & purification , Animals , Cattle , Chemical Phenomena , Chemistry , Electrophoresis, Polyacrylamide Gel , Female , Humans , Placenta/analysis , Pregnancy , Protein Denaturation
15.
Thorac Cardiovasc Surg ; 30(1): 36-8, 1982 Feb.
Article in English | MEDLINE | ID: mdl-6179231

ABSTRACT

Acute pleural empyema which is not amenable to pleural puncture or closed thoracic drainage should be treated operatively by decortication or, in persistent cavities, by open thoracostomy drainage. In the last 2 years we have instilled 500,000 IU of fibrinolysines (streptokinase and streptodornase) per day into the pleural cavity of 27 patients with pleural infections requiring closed intrapleural drainage. By means of this treatment, pus and fibrinous membranes are liquefied and necrotic tissue is discharge. Therapeutic success is indicated by considerably increased fluid drainage about one hour after instillation. This therapy was performed for an average of 5 days. In 12 patients (44%) pleural empyema could be cured. In the other 15 cases decortication, and in 3 of them open thoracostomy drainage, was necessary. In our opinion intrapleural instillation of fibrinolytic enzymes should be added to the well-recognized method of treatment of pleural empyema, although not replace them.


Subject(s)
Empyema/drug therapy , Streptodornase and Streptokinase/administration & dosage , Acute Disease , Adolescent , Adult , Aged , Child , Drainage , Humans , Injections , Male , Middle Aged , Pleura
16.
Appl Opt ; 21(6): 1035-41, 1982 Mar 15.
Article in English | MEDLINE | ID: mdl-20389800

ABSTRACT

A survey of the optical quality of commercial and experimental Selfoc GRIN-rod lenses was made using a digital Twyman-Green wave-front interferometer. The technique provides an accurate and reproducible method for predicting lens performance in microoptic devices. Wave-front aberrations are reported for (1/4) pitch lenses measured in a double-pass configuration. It was found that spherical aberration is dominant in commercial lenses. SLW (1/4) pitch lenses have lower aberrations than SLS lenses and are quite suitable for microoptic devices based on fiber-to-fiber coupling. Measured multimode coupling efficiency under steady-state modal propagation is compared to measured spherical aberration for a number of lenses. The slope of the coupling dependence on spherical aberration was found to be -0.1 dB/wave. Effects due to mechanical alignment and the modal distribution in the fibers had a greater influence on the measured coupling efficiency than the contribution due the intrinsic lens aberrations, especially for the SLW lenses. Comparison of this empirical dependence with theoretical predictions for a uniform distribution, which suggests a stronger dependence, is discussed. This work suggests that commercially available GRIN-rod lenses are suitable for use in microoptic components.

18.
Thorac Cardiovasc Surg ; 28(6): 444-5, 1980 Dec.
Article in English | MEDLINE | ID: mdl-6162221

ABSTRACT

Rare extraskeletal locations of osteoclastoma-like giant cell tumors have been found in thyroid, pancreas, breast, skin and heart. In our case, a 40-year-old male patient, such a tumor was found in the left upper lobe bronchus with atelectasis due to bronchial obstruction. Upper lobe resection was done. As far as we know, this has not been reported.


Subject(s)
Bronchial Neoplasms/diagnosis , Giant Cell Tumors/diagnosis , Adult , Bronchial Neoplasms/complications , Bronchoscopy , Giant Cell Tumors/complications , Humans , Lung/diagnostic imaging , Male , Pulmonary Atelectasis/diagnostic imaging , Pulmonary Atelectasis/etiology , Radiography
19.
Langenbecks Arch Chir ; 350(3): 199-206, 1980.
Article in German | MEDLINE | ID: mdl-6447236

ABSTRACT

Animal experiments have shown bicarbone to be a suitable material for alloplastic tracheal replacement. So far survival rates have been limited by connective tissue stenoses and by loosening prostheses. Although the transplants are not lined by bronchial mucosa, the movement of secretions is not seriously impaired due to the smooth surface. It is still a matter of speculation as to whether modifying the suture technique with a more elastic transistion from the trachea to the prosthesis would produce better results.


Subject(s)
Biocompatible Materials , Polymers , Prostheses and Implants , Trachea/surgery , Animals , Dogs , Polyethylene Terephthalates , Postoperative Complications
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