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1.
Front Psychiatry ; 15: 1342445, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38476613

RESUMO

Although endangerment towards others is a criterion for an involuntary admission in many countries, research on risk assessment of endangerment among involuntarily admitted individuals is limited. In this retrospective case-control study, we calculated scores for a German-translated version of the Violence Risk Screening-10 (V-RISK-10) and the Brøset Violence Checklist (BVC) in a sample of 111 people undergoing an involuntary admission in Reinickendorf, Berlin. Outcomes were violence, coercive measures, and readmission. In line with our hypotheses, the BVC demonstrated stronger predictive validities for short-term, and V-RISK-10 for long-term events. There was an incremental validity for both instruments for restraint 24 hours after admission and any violence until discharge. These findings support the evidence that structured risk assessment instruments may be useful for individuals undergoing an involuntary admission. Ethical considerations about screening procedures are discussed.

2.
Biol Lett ; 18(4): 20220078, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35414220

RESUMO

The Hemiptera, with approximately 98 000 species, is one of the largest insect orders. Most species feed by sucking sap from plant tissues and are thus often vectors for economically important phytopathogens. Well known within this group are the large cicadas (Cicadomorpha: Cicadoidea: Cicadidae) because they produce extremely loud airborne sounds. Less well known are their mostly tiny relatives, the leafhoppers, spittlebugs, treehoppers and planthoppers that communicate by silent vibrational signals. While the generation of these signals has been extensively investigated, the mechanisms of their perception are poorly understood. This study provides a complete description and three-dimensional reconstruction of a large and complex array of mechanoreceptors in the first abdominal segments of the Rhododendron leafhopper Graphocephala fennahi (Cicadomorpha: Membracoidea: Cicadellidae). Further, we identify homologous organs in the spittlebug Philaenus spumarius (Cicadomorpha: Cercopoidea: Aphrophoridae) and the planthopper Issus coleoptratus (Fulgoromorpha: Fulgoroidea: Issidae). Such large abdominal sensory arrays have not been found in any other insect orders studied so far. This indicates that these sense organs, together with the signal-producing tymbal organ, constitute a synapomorphy of the Tymbalia (Hemiptera excl. Sternorrhyncha). Our results contribute to the understanding of the evolution from substrate-borne to airborne communication in insects.


Assuntos
Hemípteros , Animais , Órgãos dos Sentidos
3.
Artigo em Inglês | MEDLINE | ID: mdl-33871680

RESUMO

One hundred years ago in 1921, Sir Boris Uvarov recognized that two locust species are one species but appearing in two different phases, a solitarious and a gregarious phase. As locust swarms are still a big problem affecting millions of people, basic research has tried to understand the causes for the transition between phases. This phenomenon of phase polymorphism, now called polyphenism, is a very complex multifactorial process and this short review will draw attention to this important aspect of insect research.


Assuntos
Comportamento Animal , Pesquisa Biomédica/história , Gafanhotos/fisiologia , Neurofisiologia , Animais , Aminas Biogênicas/metabolismo , Evolução Biológica , Feminino , Genótipo , Gafanhotos/genética , Gafanhotos/metabolismo , História do Século XX , História do Século XXI , Masculino , Neurofisiologia/história , Fenótipo , Feromônios/metabolismo , Densidade Demográfica , Limiar Sensorial , Comportamento Social , Especificidade da Espécie
4.
J Affect Disord ; 251: 136-140, 2019 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-30921597

RESUMO

BACKGROUND: Lithium augmentation (LA) of antidepressants is an effective strategy for treatment-resistant depression (TRD). Nevertheless, it is rarely used in geriatric patients. The purpose of this study was to investigate treatment response of LA in geriatric compared to non-geriatric patients. METHOD: In a prospective multicenter cohort study, severity of depression was measured weekly in 167 patients with unipolar depression (nage≥65years = 22; nage<65years = 145) at baseline and over at least four weeks of LA. RESULTS: Geriatric patients showed a significantly better response to LA compared to non-geriatric patients (Hazard Ratio = 1.91; p = 0.04). LIMITATIONS: An important limitation of our study is the lack of a control group of LA and the missing evaluation of side effects in both groups. CONCLUSIONS: This is the first study investigating the efficacy of LA for TRD in geriatric compared to non-geriatric patients. Our data suggest that LA is an effective treatment option in geriatric patients that clinicians might consider more frequently and earlier on in the course of treatment.


Assuntos
Antidepressivos/uso terapêutico , Transtorno Depressivo Resistente a Tratamento/tratamento farmacológico , Carbonato de Lítio/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Depressão , Transtorno Depressivo Maior/tratamento farmacológico , Quimioterapia Combinada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento
5.
J Morphol ; 279(11): 1654-1664, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30350373

RESUMO

Groups of mechanoreceptive sensilla form small sensory fields on the ventral rim of the most distal tarsomeres in insects. Within these fields two or three sensilla are located closely together. Anterior and posterior fields are found in all three pairs of legs with only a few exceptions. The composition, exact location, and morphology of the fields were studied in representative species of several insect orders using light and scanning electron microscopy. There was no obvious correlation between field morphology and insect phylogenetic relationships.


Assuntos
Extremidades/anatomia & histologia , Insetos/anatomia & histologia , Sensilas/fisiologia , Animais , Insetos/ultraestrutura , Filogenia , Sensilas/anatomia & histologia , Sensilas/citologia , Sensilas/ultraestrutura
6.
Artigo em Inglês | MEDLINE | ID: mdl-29752490

RESUMO

The current study investigates the motor innervation pattern of labral muscles in the adult locust and tries to interpret the results in the light of the hypothesis that the labrum phylogenetically developed by the fusion of paired appendages associated with the intercalary segment. Using Neurobiotin™ as a retrograde neuronal tracer, specific motor nerves or individual labral muscles were stained. Results show that the labral muscles receive innervation from tritocerebrum and suboesophageal ganglion. The axons of many motor neurons use three different pathways to cross the midline in the periphery to innervate ipsi- and contralateral muscles. Intracellular recordings from fibers of individual muscles and simultaneous recordings from motor neurons imply that the labral muscles lack inhibitory innervation. The location of motor neurons in both tritocerebrum and suboesophageal ganglion supports the notion that the labrum is innervated by the so-called intercalary segment. That many of the efferent axons cross the midline in the periphery might be explained by the hypothesis that the labrum derives from a fusion of appendages.


Assuntos
Locusta migratoria/anatomia & histologia , Neurônios Motores/citologia , Músculos/inervação , Animais , Axônios , Biotina/análogos & derivados , Feminino , Gânglios dos Invertebrados/citologia , Gânglios dos Invertebrados/fisiologia , Locusta migratoria/fisiologia , Masculino , Neurônios Motores/fisiologia , Músculos/anatomia & histologia , Músculos/fisiologia , Técnicas de Rastreamento Neuroanatômico , Marcadores do Trato Nervoso
7.
Biomicrofluidics ; 11(4): 044103, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28794814

RESUMO

A new triangle-shaped microfluidic channel system for defined cell trapping is presented. Different variants of the same basic geometry were produced to reveal the best fitting parameter combinations regarding efficiency and sensitivity. Variants with differences in the trap gap width and the inter-trap distance were analyzed in detail by Computational Fluid Dynamics simulations and in experiments with artificial beads of different sizes (30, 60, 80 µm). Simulation analysis of flow dynamics and pressure profiles revealed strongly reduced pressure conditions and balanced flow rates inside the microfluidic channels compared to commonly used systems with meandering channels. Quantitative experiments with beads showed very good trapping results in all channel types with slight variations due to geometrical differences. Highest efficiency in terms of fast trap filling and low particle loss was shown with channel types having a larger trap gap width (20 µm) and/or a larger inter-trap distance (400 µm). Here, experimental success was achieved in almost 85% to 100% of all cases. Particle loss appeared significantly more often with large beads than with small beads. A significantly reduced trapping efficiency of about 50% was determined by using narrow trap gaps and a small inter-trap distance in combination with large 80 µm beads. The combination of the same parameters with small and medium beads led to an only slight decrease in trapping efficiency (80%). All channel types were tested qualitatively with invertebrate neurons from the pond snail Lymnaea stagnalis. The systems were appropriate to trap those sensitive neurons and to keep their viability in the trapping area at the same time.

8.
Proc Biol Sci ; 284(1855)2017 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-28566485

RESUMO

To survive, web-building spiders rely on their capture threads to restrain prey. Many species use special adhesives for this task, and again the majority of those species cover their threads with viscoelastic glue droplets. Cribellate spiders, by contrast, use a wool of nanofibres as adhesive. Previous studies hypothesized that prey is restrained by van der Waals' forces and entrapment in the nanofibres. A large discrepancy when comparing the adhesive force on artificial surfaces versus prey implied that the real mechanism was still elusive. We observed that insect prey's epicuticular waxes infiltrate the wool of nanofibres, probably induced by capillary forces. The fibre-reinforced composite thus formed led to an adhesion between prey and thread eight times stronger than that between thread and wax-free surfaces. Thus, cribellate spiders employ the originally protective coating of their insect prey as a fatal component of their adhesive and the insect promotes its own capture. We suggest an evolutionary arms race with prey changing the properties of their cuticular waxes to escape the cribellate capture threads that eventually favoured spider threads with viscous glue.


Assuntos
Insetos/química , Seda/química , Aranhas , Ceras/química , Adesividade , Animais
9.
Biol Open ; 5(3): 252-5, 2016 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-26863940

RESUMO

Issus coleoptratus is a small plant hopper which mainly feeds on the phloem sap from ivy. Although all parts of ivy are poisonous as the plant contains saponins, especially hederasaponins, I. coleoptratus can cope with the poison. In contrast to other animals like the stick insect Carausius morosus which accumulates saponins in its body, I. coleoptratus can degrade and disintegrate not only the saponins but even the genines, i.e. the triterpene core of the substances. This is perhaps made possible by a specialised midgut and/or the salivary glands. When the glands and the gut are dissected and added to saponins in solution, the saponins, including the genines, are degraded ex vivo.

10.
ACS Appl Mater Interfaces ; 7(33): 18769-77, 2015 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-26237337

RESUMO

A new low cost and highly reproducible technique is presented that provides patterned cell culture substrates. These allow for selective positioning of cells and a chemically and mechanically directed guiding of their extensions. The patterned substrates consist of structured agarose hydrogels molded from reusable silicon micro templates. These templates consist of pins arranged equidistantly in squares, connected by bars, which mold corresponding wells and channels in the nonadhesive agarose hydrogel. Subsequent slice production with a standard vibratome, comprising the described template pattern, completes substrate production. Invertebrate neurons of locusts and pond snails are used for this application as they offer the advantage over vertebrate cells as being very large and suitable for cultivation in low cell density. Their neurons adhere to and grow only on the adhesive areas not covered by the agarose. Agarose slices of 50 µm thickness placed on glass, polystyrene, or MEA surfaces position and immobilize the neurons in the wells, and the channels guide their neurite outgrowth toward neighboring wells. In addition to the application with invertebrate neurons, the technique may also provide the potential for the application of a wide range of cell types. Long-term objective is the achievement of isolated low-density neuronal networks on MEAs or different culture substrates for various network analysis applications.


Assuntos
Hidrogéis/química , Neurônios/citologia , Sefarose/química , Animais , Sobrevivência Celular , Células Cultivadas , Feminino , Imuno-Histoquímica , Locusta migratoria , Masculino , Neurônios/metabolismo , Silício/química
11.
Arthropod Struct Dev ; 44(6 Pt A): 604-7, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26133086

RESUMO

Small-diameter nerves were found that are associated with the lateral peripheral nerves of the unfused abdominal ganglia of locusts. Such small nerves were observed in about 30% of all cases in Locusta migratoria, more than 60% in Schistocerca gregaria. Retrograde staining of these small nerves showed two somata in the posterior, lateral, and ventral region of an abdominal ganglion. These cells give rise to the small nerves that accompany the big lateral nerves and, on their surface, form putative neurohaemal release sites. Astonishingly the cells do not form any dendritic ramifications within the neuropile of the ganglia.


Assuntos
Gafanhotos/citologia , Animais , Dendritos , Feminino , Locusta migratoria/citologia , Masculino , Microscopia Confocal , Neurônios/citologia , Sistemas Neurossecretores/citologia
13.
Cell Tissue Res ; 358(2): 303-12, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25107605

RESUMO

Based on experience with cell cultures of adult insect neurons, we develop a serum-free culture system for embryonic locust neurons. Influences of trophic substances on survival and neurite outgrowth of developing neurons are investigated. For the first time, a positive trophic effect of 9-cis retinoic acid (9-cis RA) was shown in vitro on embryonic neurons of an insect. We observed longer cell survival of 50 % developmental stage neurons in cultures supplemented with 0.3 nM 9-cis RA. Furthermore, an influence on neuron morphology was revealed, as the addition of 9-cis RA to cell culture medium led to an increase in the number of neurites per cell. Although an RA receptor gene, LmRXR (Locusta migratoria retinoid X receptor), was expressed in the central nervous system throughout development, the influence of 9-cis RA on neuronal survival and outgrowth was restricted to 50 % stage embryonic cells.


Assuntos
Locusta migratoria/citologia , Neurônios/citologia , Tretinoína/farmacologia , Alitretinoína , Animais , Diferenciação Celular/efeitos dos fármacos , Forma Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Ácidos Docosa-Hexaenoicos/farmacologia , Embrião não Mamífero/citologia , Embrião não Mamífero/efeitos dos fármacos , Locusta migratoria/embriologia , Neuritos/efeitos dos fármacos , Neuritos/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Receptores do Ácido Retinoico/metabolismo
15.
Front Zool ; 10(1): 54, 2013 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-24015902

RESUMO

BACKGROUND: The great majority of afferent neurons of insect legs project into their segmental ganglion. Intersegmental projections are rare and are only formed by sense organs associated with the basal joints of the legs. Such intersegmental projections never ascend as far as the brain and they form extensive ramifications within thoracic ganglia. A few afferents of chordotonal organs of the subcoxal joints ascend as far as the suboesophageal ganglion. RESULTS: We describe novel afferent neurons in distal segments of locust legs that project directly into the brain without forming ramifications in other ganglia. In the brain, the fibres terminate with characteristic terminals in a small neuropile previously named the superficial ventral inferior protocerebrum. The somata of these neurons are located in the tibiae and tarsi of all legs and they are located within branches of peripheral nerves, or closely associated with such branches. They are not associated with any accessory structures such as tendons or connective tissue strands as typical for insect internal mechanoreceptors such as chordotonal organs or stretch receptors. Morphologically they show great similarity to certain insect infrared receptors.We could not observe projections into the superficial ventral inferior protocerebrum after staining mandibular or labial nerves, but we confirm previous studies that showed projections into the same brain neuropile after staining maxillary and antennal nerves, indicating that most likely similar neurons are present in these appendages also. CONCLUSION: Because of their location deep within the lumen of appendages the function of these neurons as infrared receptors is unlikely. Their projection pattern and other morphological features indicate that the neurons convey information about an internal physiological parameter directly into a special brain neuropile. We discuss their possible function as thermoreceptors.

16.
Arthropod Struct Dev ; 42(6): 507-520, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24067539

RESUMO

It is well established that the brains of adult malacostracan crustaceans and winged insects display distinct homologies down to the level of single neuropils such as the central complex and the optic neuropils. We wanted to know if developing insect and crustacean brains also share similarities and therefore have explored how neurotransmitter systems arise during arthropod embryogenesis. Previously, Sintoni et al. (2007) had already reported a homology of an individually identified cluster of neurons in the embryonic crayfish and insect brain, the secondary head spot cells that express the Engrailed protein. In the present study, we have documented the ontogeny of the serotonergic system in embryonic brains of the Marbled Crayfish in comparison to Migratory Locust embryos using immunohistochemical methods combined with confocal laser-scan microscopy. In both species, we found a cluster of early emerging serotonin-immunoreactive neurons in the protocerebrum with neurites that cross to the contralateral brain hemisphere in a characteristic commissure suggesting a homology of this cell cluster. Our study is a first step towards a phylogenetic analysis of neurotransmitter system development and shows that, as for the ventral nerve cord, traits related to neurogenesis in the brain can provide valuable hints for resolving the much debated question of arthropod phylogeny.


Assuntos
Astacoidea/embriologia , Encéfalo/embriologia , Gafanhotos/embriologia , Rede Nervosa/citologia , Migração Animal , Animais , Astacoidea/citologia , Astacoidea/crescimento & desenvolvimento , Encéfalo/citologia , Gafanhotos/citologia , Gafanhotos/crescimento & desenvolvimento , Imuno-Histoquímica , Rede Nervosa/efeitos dos fármacos , Rede Nervosa/ultraestrutura , Neurotransmissores , Serotonina/metabolismo , Serotonina/farmacologia
17.
Arthropod Struct Dev ; 41(5): 443-58, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22750128

RESUMO

The sensory pits of the nymphs of the planthopper Issus coleoptratus were investigated using light and electron microscopic techniques. Sensory pits consist of a bowl-shaped depression in the cuticle (25-70 µm in diameter) covered by a transparent cupola of presumably waxy material. Each pit is equipped with a long sensory hair that emerges from the inner wall of the pit and extends horizontally for about two thirds of the pit diameter. The cupola emerges from the rim of the pit opposite to the socket of this hair. Additional small sensory hairs extend into the base of the cupola. While the ultrastructure of these small hairs resembles that of other mechanoreceptive sensory hairs of insects, that of the long hairs shows several peculiarities. Sensory pits are dispersed over the frontal part of the head, the tergites of thoracic and abdominal segments. On the different parts of the exoskeleton, the orientation of long hairs within the pits varies in a systematic fashion with respect to the body axes. Size, location, and orientation of the pits show almost perfect bilateral symmetry. Their number increases with each moult. Comparative data show that the level of structural complexity of these sense organs varies considerably within this group of insects.


Assuntos
Hemípteros/ultraestrutura , Animais , Alemanha , Hemípteros/anatomia & histologia , Hemípteros/genética , Hemípteros/crescimento & desenvolvimento , Mecanorreceptores/citologia , Mecanorreceptores/ultraestrutura , Microscopia Confocal , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Ninfa/anatomia & histologia , Ninfa/crescimento & desenvolvimento , Ninfa/ultraestrutura , Órgãos dos Sentidos/anatomia & histologia , Órgãos dos Sentidos/crescimento & desenvolvimento , Órgãos dos Sentidos/ultraestrutura , Especificidade da Espécie
18.
J Mol Histol ; 43(4): 405-19, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22403023

RESUMO

We have designed a cell culture system for thoracic neurons of adult Locusta migratoria that enables the establishment of functional synapses in vitro. Patch-clamp recordings revealed three different neuron classes. About half of the neurons (47%) had unexcitable somata with outward and no inward conductance. The other half generated either single (37%) or multiple action potentials (18%) and differed mainly in lower outward conductance. Selectively stained motor neurons were analyzed to demonstrate varied physiological properties due to culture conditions. Using paired patch clamp recordings we demonstrate directly synaptic transmission in morphologically connected neurons in vitro. Presynaptic stimulation resulted in postsynaptic potentials in 42 pairs of neurons tested, independent of the type of neuron. According to pharmacological experiments most of these synapses were either glutamatergic or GABAergic. In addition to these chemical synapses, electrical synapses were found. With the demonstration of synapse formation in cell culture of adult locust neurons, this study provides the basis for the future analysis of more defined insect neuronal circuits in culture.


Assuntos
Sinapses Elétricas/fisiologia , Gafanhotos/fisiologia , Neurônios Motores , Transmissão Sináptica/fisiologia , Potenciais de Ação/fisiologia , Animais , Técnicas de Cultura de Células , Sinapses Elétricas/efeitos dos fármacos , Feminino , GABAérgicos/farmacologia , Gânglios/citologia , Gânglios/fisiologia , Masculino , Neurônios Motores/citologia , Neurônios Motores/efeitos dos fármacos , Neurônios Motores/fisiologia , Técnicas de Patch-Clamp , Estimulação Química , Transmissão Sináptica/efeitos dos fármacos
19.
Arthropod Struct Dev ; 40(3): 210-20, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21256976

RESUMO

Here we describe the neuronal organization of the arcuate body in the brain of the wandering spider Cupiennius salei. The internal anatomy of this major brain center is analyzed in detail based on allatostatin-, proctolin-, and crustacean cardioactive peptide (CCAP)-immunohistochemistry. Prominent neuronal features are demonstrated in graphic reconstructions. The stainings revealed that the neuroarchitecture of the arcuate body is characterized by several distinct layers some of which comprise nerve terminals that are organized in columnar, palisade-like arrays. The anatomy of the spider's arcuate body exhibits similarities as well as differences when compared to the central complex in the protocerebrum of the Tetraconata. Arguments for and against a possible homology of the arcuate body of the Chelicerata and the central complex of the Tetraconata and their consequences for the understanding of arthropod brain evolution are discussed.


Assuntos
Evolução Biológica , Calcitonina/metabolismo , Neuropeptídeos/metabolismo , Oligopeptídeos/metabolismo , Fragmentos de Peptídeos/metabolismo , Aranhas/anatomia & histologia , Aranhas/genética , Animais , Encéfalo/citologia , Encéfalo/fisiologia , Calcitonina/genética , Regulação da Expressão Gênica , Imuno-Histoquímica , Neuropeptídeos/genética , Oligopeptídeos/genética , Fragmentos de Peptídeos/genética , Coloração e Rotulagem
20.
J Affect Disord ; 129(1-3): 75-8, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20869775

RESUMO

OBJECTIVE: Weight increase is a problem in women with bipolar disorder (BD). Furthermore, there is evidence that both binge eating disorder (BED) and menstrual cycle abnormalities occur more frequently in women with affective disorders than in the general population. We investigated whether there is a clinical link between the two disorders and menstrual cycle. METHOD: Epidemiological and clinical variables associated with both BD and BED were assessed as well as menstrual cycle influence. RESULTS: The prevalence of BED in the sample was 28.8%. Menstrual cycle significantly influenced BED in all participants in that BED became worse prior to menses. 80% of the participants noticed regular weight gain prior to menses. DISCUSSION: BED is a common comorbidity in unmedicated subjects with BD, as is overweight. In women with BD menstrual cycle should be taken into consideration, as it can worsen the BD itself and associated comorbidities such as BED and overweight. Alteration in menstrual cycle-associated eating behavior should be routinely assessed in women with BD.


Assuntos
Transtorno da Compulsão Alimentar/fisiopatologia , Transtorno Bipolar/fisiopatologia , Ciclo Menstrual/psicologia , Adulto , Transtorno da Compulsão Alimentar/epidemiologia , Transtorno da Compulsão Alimentar/psicologia , Transtorno Bipolar/epidemiologia , Transtorno Bipolar/psicologia , Distribuição de Qui-Quadrado , Comorbidade , Feminino , Humanos , Escalas de Graduação Psiquiátrica , Estatísticas não Paramétricas , Adulto Jovem
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