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1.
Adv Exp Med Biol ; 1131: 881-900, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31646538

RESUMO

Drosophila melanogaster, colloquially known as the fruit fly, is one of the most commonly used model organisms in scientific research. Although the final architecture of a fly and a human differs greatly, most of the fundamental biological mechanisms and pathways controlling development and survival are conserved through evolution between the two species. For this reason, Drosophila has been productively used as a model organism for over a century, to study a diverse range of biological processes, including development, learning, behavior and aging. Ca2+ signaling comprises complex pathways that impact on virtually every aspect of cellular physiology. Within such a complex field of study, Drosophila offers the advantages of consolidated molecular and genetic techniques, lack of genetic redundancy and a completely annotated genome since 2000. These and other characteristics provided the basis for the identification of many genes encoding Ca2+ signaling molecules and the disclosure of conserved Ca2+ signaling pathways. In this review, we will analyze the applications of Ca2+ imaging in the fruit fly model, highlighting in particular their impact on the study of normal brain function and pathogenesis of neurodegenerative diseases.


Assuntos
Cálcio , Drosophila melanogaster , Animais , Encéfalo/fisiologia , Encéfalo/fisiopatologia , Cálcio/metabolismo , Drosophila melanogaster/fisiologia , Humanos , Modelos Animais
2.
Adv Exp Med Biol ; 1131: 901-942, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31646539

RESUMO

The zebrafish (Danio rerio) has emerged as a widely used model system during the last four decades. The fact that the zebrafish larva is transparent enables sophisticated in vivo imaging, including calcium imaging of intracellular transients in many different tissues. While being a vertebrate, the reduced complexity of its nervous system and small size make it possible to follow large-scale activity in the whole brain. Its genome is sequenced and many genetic and molecular tools have been developed that simplify the study of gene function in health and disease. Since the mid 90's, the development and neuronal function of the embryonic, larval, and later, adult zebrafish have been studied using calcium imaging methods. This updated chapter is reviewing the advances in methods and research findings of zebrafish calcium imaging during the last decade. The choice of calcium indicator depends on the desired number of cells to study and cell accessibility. Synthetic calcium indicators, conjugated to dextrans and acetoxymethyl (AM) esters, are still used to label specific neuronal cell types in the hindbrain and the olfactory system. However, genetically encoded calcium indicators, such as aequorin and the GCaMP family of indicators, expressed in various tissues by the use of cell-specific promoters, are now the choice for most applications, including brain-wide imaging. Calcium imaging in the zebrafish has contributed greatly to our understanding of basic biological principles during development and adulthood, and the function of disease-related genes in a vertebrate system.


Assuntos
Cálcio , Peixe-Zebra , Animais , Encéfalo/diagnóstico por imagem , Cálcio/metabolismo , Modelos Animais , Neurônios/fisiologia , Peixe-Zebra/fisiologia
3.
Zhonghua Wai Ke Za Zhi ; 57(11): 853-859, 2019 Nov 01.
Artigo em Chinês | MEDLINE | ID: mdl-31694135

RESUMO

Objective: To establish experimental porcine model of reconstruction the neobladder by ileal seromuscular with transplantation of autologous peritoneum. Methods: This was an animal experiment carried out from January to April 2018 at animal center of Guizhou Medical University. Randomly 6 experimental female porcines were chosen, and their body weight was 28 to 33 kg. By intravenous anesthesia, the transplantation of autologous peritoneum for bladder reconstruction operation was carried out by transplanting the peritoneum onto an ileum segment which mucosa and submucosa had been removed. These flaps were used to mend and reconstruct the neobladder by suturing with edge of the detective bladder. After removal of ureteral catheters and balloon catheter at day 5 and day 7 respectively, voiding behavior was monitored, and animals were euthanized at week 12 for routine pathology, immunohistochemistry, and electron microscopic examinations. Results: Six porcines underwent reconstruction, but no one lost to complications such as peritonitis, ileus and urinary fistula. Voiding behavior was normal, and urine was clear in all animals after removal of catheters. At autopsy, reconstructed bladders were healthy. Pathological examination showed the part of reconstruction had been covered by continuous urothelium while the peritoneum disappeared and showed no ileal mucosa regrowth and residual. Scanning electron microscope showed that the transitional cells of neobladder were complete and orderly, and urothelium around suture border was continuous and no malposition. Conclusion: In this experimental porcine model, reconstruction bladder by autologous peritoneum and ileal seromuscular flaps is an ideal approach.


Assuntos
Íleo/transplante , Peritônio/transplante , Neoplasias da Bexiga Urinária/cirurgia , Derivação Urinária/métodos , Procedimentos Cirúrgicos Urológicos/métodos , Animais , Cistectomia , Feminino , Modelos Animais , Distribuição Aleatória , Procedimentos Cirúrgicos Reconstrutivos/métodos , Retalhos Cirúrgicos , Suínos , Transplante Autólogo
4.
Braz J Med Biol Res ; 52(11): e8899, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31664307

RESUMO

Few behavioral tests allow measuring several characteristics and most require training, complex analyses, and/or are time-consuming. We present an apparatus based on rat exploratory behavior. Composed of three different environments, it allows the assessment of more than one behavioral characteristic in a short 3-min session. Factorial analyses have defined three behavioral dimensions, which we named Exploration, Impulsivity, and Self-protection. Behaviors composing the Exploration factor were increased by chlordiazepoxide and apomorphine and decreased by pentylenetetrazole. Behaviors composing the Impulsivity factor were increased by chlordiazepoxide, apomorphine, and both acute and chronic imipramine treatments. Behaviors composing the Self-protection factor were decreased by apomorphine. We submitted Wistar rats to the open-field test, the elevated-plus maze, and to the apparatus we are proposing. Measures related to exploratory behavior in all three tests were correlated. Measures composing the factors Impulsivity and Self-protection did not correlate with any measures from the two standard tests. Also, compared with existing impulsivity tests, the one we proposed did not require previous learning, training, or sophisticated analysis. Exploration measures from our test are as easy to obtain as the ones from other standard tests. Thus, we have proposed an apparatus that measured three different behavioral characteristics, was simple and fast, did not require subjects to be submitted to previous learning or training, was sensitive to drug treatments, and did not require sophisticated data analyses.


Assuntos
Ansiedade/psicologia , Comportamento Animal/fisiologia , Pesquisa Comportamental/instrumentação , Comportamento Exploratório/fisiologia , Medo/fisiologia , Comportamento Impulsivo/fisiologia , Animais , Ansiolíticos/farmacologia , Antidepressivos Tricíclicos/farmacologia , Apomorfina/farmacologia , Comportamento Animal/efeitos dos fármacos , Clordiazepóxido/farmacologia , Agonistas de Dopamina/farmacologia , Comportamento Exploratório/efeitos dos fármacos , Medo/efeitos dos fármacos , Antagonistas GABAérgicos/farmacologia , Comportamento Impulsivo/efeitos dos fármacos , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Aprendizagem em Labirinto/fisiologia , Modelos Animais , Pentilenotetrazol/farmacologia , Ratos Wistar , Fatores de Tempo
5.
Zhonghua Shao Shang Za Zhi ; 35(9): 692-696, 2019 Sep 20.
Artigo em Chinês | MEDLINE | ID: mdl-31594189

RESUMO

The occurrence, development, and prognosis of burn is a complicated pathophysiological process involving many organs and systems. With the development of science and technology and update of treatment concept, more and more new materials, new equipments, and new methods are applied to the diagnosis and treatment of burn. Animals similar to humans in anatomical structure and physiological function are the ideal models for research of burn. Nowadays, animal models of burn have been developed to simulate different aspects of burn. These models provide important essential support for elucidating the pathophysiological mechanism of burns and exploring new therapeutic interventions and materials for human beings. Understanding the advantages and limitations of these animal models is essential for the research of burn.


Assuntos
Queimaduras , Modelos Animais , Cicatrização , Animais , Humanos
6.
Acta Cir Bras ; 34(8): e201900803, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31618403

RESUMO

PURPOSE: To evaluate changes in the quantity of elastic fibers in the corpora cavernosa of rats during the natural aging process, and to assess the degree of this change by determining volumetric density (Vv) at different ages via stereological analysis. METHODS: Forty-eight rats, raised under similar conditions, were subjected to the natural aging process and divided into four groups (G1 to G4), according to age at the time of penectomy (6, 9, 12, and 24 months, respectively). Histological sections of the middle segment of the penis were stained with Weigert's resorcin-fuchsin, and the volumetric density (Vv) of elastic fibers of the corpora cavernosa were determined via stereological analysis. RESULTS: There were no statistically significant differences in Vv among groups G1, G2, and G3. These three groups were therefore considered as a single group. The mean Vv of this group showed a statistically significant reduction compared to that of G4 (0.16 vs. 0.11, p<0.05). CONCLUSION: Natural aging in rats was responsible for a reduction in volumetric density of elastic fibers of the corpora cavernosa (approximately 30% decrease in Vv) during senescence.


Assuntos
Envelhecimento/fisiologia , Tecido Elástico/ultraestrutura , Células Endoteliais/fisiologia , Pênis/citologia , Envelhecimento/patologia , Animais , Colágeno/fisiologia , Colágeno/ultraestrutura , Tecido Elástico/patologia , Tecido Elástico/fisiologia , Disfunção Erétil/fisiopatologia , Masculino , Modelos Animais , Pênis/fisiologia , Ratos , Ratos Wistar
7.
Adv Exp Med Biol ; 1186: 141-170, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31654389

RESUMO

Developing successful surgical strategies to deliver cell therapeutics to the back of the eye is an essential pillar to success for stem cell-based applications in blinding retinal diseases. Within this chapter, we have attempted to gather all key considerations during preclinical animal trials.Guidance is provided for choices on animal models, options for immunosuppression, as well as anesthesia. Subsequently we cover surgical strategies for RPE graft delivery, both as suspension as well as in monolayers in small rodents, rabbits, pigs, and nonhuman primate. A detailed account is given in particular on animal variations in vitrectomy and subretinal surgery, which requires a considerable learning curve, when transiting from human to animal. In turn, however, many essential subretinal implantation techniques in large-eyed animals are directly transferrable to human clinical trial protocols.A dedicated subchapter on photoreceptor replacement provides insights on preparation of suspension as well as sheet grafts, to subsequently outline the basics of subretinal delivery via both the transscleral and transvitreal route. In closing, a future outlook on vision restoration through retinal cell-based therapeutics is presented.


Assuntos
Terapia Baseada em Transplante de Células e Tecidos , Retina , Doenças Retinianas , Epitélio Pigmentado da Retina , Animais , Humanos , Imunossupressão , Modelos Animais , Células Fotorreceptoras/citologia , Retina/cirurgia , Doenças Retinianas/cirurgia , Doenças Retinianas/terapia , Epitélio Pigmentado da Retina/cirurgia
8.
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue ; 31(9): 1061-1071, 2019 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-31657326

RESUMO

OBJECTIVE: Preclinical animal studies are mandatory before new treatments can be tested in clinical trials. However, their use in developing new therapies for sepsis has been controversial because of limitations of the models and inconsistencies with the clinical conditions. In consideration of the revised definition for clinical sepsis and septic shock (Sepsis-3), a Wiggers-Bernard Conference was held in Vienna in May 2017 to propose standardized guidelines on preclinical sepsis modeling. The participants conducted a literature review of 260 most highly cited scientific articles on sepsis models published between 2003 and 2012. The review showed, for example, that mice were used in 79% and euthanasia criteria were defined in 9% of the studies. PartIof this report details the recommendations for study design and humane modeling endpoints that should be addressed in sepsis models. The first recommendation is that survival follow-up should reflect the clinical time course of the infectious agent used in the sepsis model. Furthermore, it is recommended that therapeutic interventions should be initiated after the septic insult replicating clinical care. To define an unbiased and reproducible association between a new treatment and outcome, a randomization and blinding of treatments as well as inclusion of all methodological details in scientific publications is essential. In all preclinical sepsis studies, the high standards of animal welfare must be implemented. Therefore, development and validation of specific criteria for monitoring pain and distress, and euthanasia of septic animals, as well as the use of analgesics are recommended. A set of four considerations is also proposed to enhance translation potential of sepsis models. Relevant biological variables and comorbidities should be included in the study design and sepsis modeling should be extended to mammalian species other than rodents. In addition, the need for source control (in case of a defined infection focus) should be considered. These recommendations and considerations are proposed as "best practices" for animal models of sepsis that should be implemented.


Assuntos
Sepse , Choque Séptico , Animais , Camundongos , Modelos Animais , Projetos de Pesquisa
9.
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue ; 31(9): 1091-1096, 2019 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-31657331

RESUMO

OBJECTIVE: To investigate the effect and mechanism of autophagy on the expression of neutrophil programmed death ligand-1 (PD-L1) in mice with sepsis. METHODS: (1) In vivo experiment: male C57BL/6 mice aged 6-8 weeks were divided into sham operation group (Sham group), cecum ligation and perforation (CLP) group, and rapamycin (RAP)+CLP group by random number table with 10 mice in each group. The sepsis model was reproduced by CLP, and the cecum and perforation were not ligated in Sham group, and other operations were the same as CLP group. The mice in RAP+CLP group were intraperitoneally injected with autophagy agonist RAP 4 mg×kg-1×d-1 7 days before modeling, while the mice in Sham group and CLP group were not treated. Lung, liver, spleen and pancreas tissues were harvested for immunohistochemical staining 4 days after the operation, and the infiltration of neutrophils in various organs was observed under light microscope. Meanwhile, the expressions of immunosuppressive molecule PD-L1 and autophagy marker microtubule-associated protein 1 light chain 3 (LC3) in lung neutrophils were determined by immunofluorescence staining. (2) In vitro experiment: mouse bone marrow neutrophils were extracted and re-suspended to 1×1010/L, and they were divided into blank control group (without any treatment), RAP control group (RAP 100 µmol/L), autophagy inhibitor Bafilomycin A1 (Baf) control group (Baf 10 µmol/L), lipopolysaccharide (LPS) stimulation group (LPS 1 mg /L), RAP+LPS group, and Baf+LPS group. The latter two groups were pretreated with 100 µmol/L RAP or 10 µmol/L Baf 30 minutes before LPS stimulation, respectively. The expression of PD-L1 mRNA of neutrophils was determined by reverse transcription-polymerase chain reaction (RT-PCR) at 0, 4, 12 hours after LPS stimulation. At the same time, the expressions of PD-L1, LC3 and p62 at the protein level were determined by Western Blot. RESULTS: (1) In vivo experiment: according to immunohistochemical experiments, a large amount of infiltration of neutrophils in lung, liver, spleen and pancreas was found at 4 hours after CLP. In the immunofluorescence, with the time extension after CLP, the positive expression of LC3 in the lung tissue showed a decreased tendency, and PD-L1 expression was significantly increased. RAP pretreatment could promote the expression of LC3 and reduce the expression of PD-L1 in CLP mice. (2) In vitro experiment: in terms of mRNA levels, with the extension of LPS stimulation time, the expression of PD-L1 mRNA in mouse neutrophils was increased continuously, and peaked at 12 hours, it was significantly higher than that in the blank control group (2-ΔΔCT: 72.2±10.0 vs. 13.0±0.8, P < 0.01). Compared with LPS stimulation group, the expression of PD-L1 mRNA in RAP+LPS group was significantly down-regulated [12-hour PD-L1 mRNA (2-ΔΔCT): 47.4±7.3 vs. 72.2±10.0, P < 0.01]. In Baf+LPS group, PD-L1 mRNA expression was significantly up-regulated as compared with that in LPS stimulation group [12-hour PD-L1 mRNA (2-ΔΔCT): 109.1±7.4 vs. 72.2±10.0, P < 0.01]. At the protein levels, at 4 hours after LPS stimulation, the positive expressions of PD-L1, LC3 and p62 were increased significantly as compared with those in the blank control group, and PD-L1 and p62 were increased continuously with time. Compared with the LPS stimulation group, the expressions of PD-L1 and p62 in the RAP+LPS group were significantly down-regulated, while the expression of LC3 was continually increased, indicating that the level of autophagy was increased, and autophagy was circulated smoothly. On the contrary, the expressions of PD-L1, LC3 and p62 in the Baf+LPS group were significantly up-regulated, indicating that the binding of autophagy and lysosome was blocked, and autophagy was not smooth. CONCLUSIONS: In sepsis, the infiltration of neutrophils in all organs increased, and the expression of PD-L1 of neutrophils in lungs was increased significantly, while the expression level of autophagy was decreased. The expression of PD-L1 stimulated by LPS can be inhibited by autophagy agonists, and promoted by autophagy inhibitors. PD-L1 has a negative regulatory effect on sepsis. It can reduce the expression of PD-L1 molecule in sepsis by targeting autophagy, so as to improve sepsis.


Assuntos
Autofagia , Sepse , Animais , Antígeno B7-H1/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Modelos Animais , Neutrófilos
10.
Int J Nanomedicine ; 14: 7781-7792, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31576122

RESUMO

Purpose: Mesoporous silica (MS) have been considered as a biocompatible compound and found to have various pharmaceutical applications. Recently, novel approaches in applications of MS as antidote agents were introduced. In this study, the capacity of ethylenediaminetetraacetic acid modified mesoporous silica (MS-EDTA) was evaluated in in vitro and in vivo adsorption of copper (Cu). Methods: The MS-EDTA was characterized by fourier transform infrared (FT-IR) and X-ray diffraction, while surface area was determined by N2 adsorption-desorption technique. Morphological studies were observed by high resolution-transmission electron microscopy and field emission-scanning electron microscopy and the sizes were determined by dynamic light scattering. The capacity of these particles for copper adsorption was investigated in vitro in both 1.2 and 7.2 pH. In in vivo animal study, the Cu adsorption efficiency of MS-EDTA in Cu-overdosed mice was evaluated. In this case, an animal model of acute copper poisoning was prepared. Results: The MS-EDTA with surface area of 352.35 was synthesized. Scanning electron microscope showed spherical particle formation with less than 500 nm in size. Transmission electron microscope images showed porous and honeycomb structure. FT-IR spectroscopy showed an appropriate formation of functional groups. Particle efficiency was investigated for Cu adsorption. MS-EDTA in both media showed a high adsorption capability for Cu (II) adsorption in pH=1.2 and pH=7.2. In addition, the study of Langmuir, Freundlich, and Redlich-Peterson adsorption models showed that copper adsorption by MS-EDTA followed the Freundlich model with multi-layer adsorption. In vivo evaluation showed that MS-EDTA could alleviate the symptoms of acute copper poisoning by lowering Cu plasma levels. Conclusion: Structural evaluation showed successful formation of MS-EDTA. In vitro analysis demonstrated that supreme Cu adsorption occurs in both pH conditions (7.2 and 1.2), and was especially more favorable in simulated intestinal pH (7.2). The in vivo studies in animal models with acute Cu poisoning showed that MS-EDTA could be a potent antidote agent.


Assuntos
Antídotos/farmacologia , Cobre/isolamento & purificação , Cobre/toxicidade , Ácido Edético/química , Dióxido de Silício/química , Adsorção , Animais , Antídotos/administração & dosagem , Biomarcadores/sangue , Cobre/sangue , Difusão , Íons , Cinética , Camundongos , Modelos Animais , Tamanho da Partícula , Porosidade , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
11.
Results Probl Cell Differ ; 68: 3-20, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31598850

RESUMO

This chapter reflects on and makes explicit the distinctiveness of reasoning practices associated with model organisms in the context of evolutionary developmental research. Model organisms in evo-devo instantiate a unique synthesis of model systems strategies from developmental biology and comparative strategies from evolutionary biology that negotiate a tension between developmental conservation and evolutionary change to address scientific questions about the evolution of development and the developmental basis of evolutionary change. We review different categories of model systems that have been advanced to understand practices found in the life sciences in order to comprehend how evo-devo model organisms instantiate this synthesis in the context of three examples: the starlet sea anemone and the evolution of bilateral symmetry, leeches and the origins of segmentation in bilaterians, and the corn snake to understand major evolutionary change in axial and appendicular morphology.


Assuntos
Evolução Biológica , Biologia do Desenvolvimento , Modelos Animais , Animais , Sanguessugas/embriologia , Anêmonas-do-Mar/embriologia , Serpentes/embriologia
12.
Results Probl Cell Differ ; 68: 63-105, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31598853

RESUMO

The urochordate Oikopleura dioica is emerging as a nonclassical animal model in the field of evolutionary developmental biology (a.k.a. evo-devo) especially attractive for investigating the impact of gene loss on the evolution of mechanisms of development. This is because this organism fulfills the requirements of an animal model (i.e., has a simple and accessible morphology, a short generation time and life span, and affordable culture in the laboratory and amenable experimental manipulation), but also because O. dioica occupies a key phylogenetic position to understand the diversification and origin of our own phylum, the chordates. During its evolution, O. dioica genome has suffered a drastic process of compaction, becoming the smallest known chordate genome, a process that has been accompanied by exacerbating amount of gene losses. Interestingly, however, despite the extensive gene losses, including entire regulatory pathways essential for the embryonic development of other chordates, O. dioica retains the typical chordate body plan. This unexpected situation led to the formulation of the so-called inverse paradox of evo-devo, that is, when a genetic diversity is able to maintain a phenotypic unity. This chapter reviews the biological features of O. dioica as a model animal, along with the current data on the evolution of its genes and genome. We pay special attention to the numerous examples of gene losses that have taken place during the evolution of this unique animal model, which is helping us to understand to which the limits of evo-devo can be pushed off.


Assuntos
Biologia do Desenvolvimento , Evolução Molecular , Deleção de Genes , Modelos Animais , Urocordados/embriologia , Urocordados/genética , Animais , Filogenia
13.
Results Probl Cell Differ ; 68: 183-216, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31598857

RESUMO

All extant species are an outcome of nature's "experiments" during evolution, and hence multiple species need to be studied and compared to gain a thorough understanding of evolutionary processes. The field of evolutionary developmental biology (evo-devo) aspires to expand the number of species studied, because most functional genetic studies in animals have been limited to a small number of "traditional" model organisms, many of which belong to the same phylum (Chordata). The phylum Arthropoda, and particularly its component class Insecta, possesses many important characteristics that are considered favorable and attractive for evo-devo research, including an astonishing diversity of extant species and a wide disparity in body plans. The development of the most thoroughly investigated insect genetic model system to date, the fruit fly Drosophila melanogaster (a holometabolous insect), appears highly derived with respect to other insects and indeed with respect to most arthropods. In comparison, crickets (a basally branching hemimetabolous insect lineage compared to the Holometabola) are thought to embody many developmental features that make them more representative of insects. Here we focus on crickets as emerging models to study problems in a wide range of biological areas and summarize the currently available molecular, genomic, forward and reverse genetic, imaging and computational tool kit that has been established or adapted for cricket research. With an emphasis on the cricket species Gryllus bimaculatus, we highlight recent efforts made by the scientific community in establishing this species as a laboratory model for cellular biology and developmental genetics. This broad toolkit has the potential to accelerate many traditional areas of cricket research, including studies of adaptation, evolution, neuroethology, physiology, endocrinology, regeneration, and reproductive behavior. It may also help to establish newer areas, for example, the use of crickets as animal infection model systems and human food sources.


Assuntos
Gryllidae/genética , Gryllidae/fisiologia , Modelos Animais , Animais , Drosophila melanogaster , Abastecimento de Alimentos , Gryllidae/embriologia , Gryllidae/microbiologia
14.
Results Probl Cell Differ ; 68: 217-230, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31598858

RESUMO

Creophilus maxillosus (Staphylinidae, Coleoptera, Polyphaga) has a meroistic-telotrophic ovary composed of tropharium, which contains trophocytes (nurse cells) and vitellarium, which contains growing oocytes. The trophocytes are connected to the oocytes by cytoplasmic nutritive cords, which deliver nutrients to the oocytes. The formation/differentiation of the oocytes and trophocytes takes place in the pupal ovary within linear chains of sibling cells. Each chain is composed of a single oocyte connected to a linear chain of sister trophocytes. The nuclei of the oocytes contain an extrachromosomal DNA body (extra DNA body) consisting of amplified ribosomal DNA (rDNA). During oogenesis, the prospective oocyte, located at the base (posterior) of each chain, is the only cell within the chain that amplifies rDNA and retains permanent contact with the somatic pre-follicular cells. The oogonial divisions leading to the formation of the oocyte/trophocytes chain are asymmetric, and during consecutive divisions, the rDNA body always segregates basally (posteriorly) to the prospective oocyte abutted on the somatic cells. However, the segregation of rDNA is imperfect, and within each oocyte/trophocytes chain, there is a gradient of rDNA: the prospective oocyte has the highest amount of rDNA and the trophocyte that is most distant (most anterior) from the oocyte has no or the lowest amount of rDNA. In addition, the divisions within each chain are parasynchronous, with the pro-oocyte being the most mitotically advanced cell in the chain. These observations indicate the presence of a signaling gradient emanating from the somatic cells and/or oocyte; this gradient diminishes in strength with the increasing distance from its source, i.e., the oocyte/somatic cells. Because of this phenomenon, C. maxillosus is the perfect model in which to study the germ-somatic cell interactions and signaling. This chapter describes the methods for the collection and laboratory culture of C. maxillosus and the analysis of divisions and signaling in the C. maxillosus ovary.


Assuntos
Diferenciação Celular , Divisão Celular , Besouros/citologia , Modelos Animais , Oócitos/citologia , Transdução de Sinais , Animais , Feminino , Ovário/citologia
15.
Results Probl Cell Differ ; 68: 231-249, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31598859

RESUMO

The invertebrate phylum Tardigrada has received much attention for containing species adapted to the most challenging environmental conditions where an ability to survive complete desiccation or freezing in a cryptobiotic state is necessary for persistence. Although research on tardigrades has a long history, the last decade has seen a dramatic increase in molecular biological ("omics") studies, most of them with the aim to reveal the biochemical mechanisms behind desiccation tolerance of tardigrades. Several other aspects of tardigrade cell biology have been studied, and we review some of them, including karyology, embryology, the role of storage cells, and the question of whether tardigrades are eutelic animals. We also review some of the theories about how anhydrobiotic organisms are able to maintain cell integrity under dry conditions, and our current knowledge on the role of vitrification and DNA protection and repair. Many aspects of tardigrade stress tolerance have relevance for human medicine, and the first transfers of tardigrade stress genes to human cells have now appeared. We expect this field to develop rapidly in the coming years, as more genomic information becomes available. However, many basic cell biological aspects remain to be investigated, such as immunology, cell cycle kinetics, cell metabolism, and culturing of tardigrade cells. Such development will be necessary to allow tardigrades to move from a nonmodel organism position to a true model organism with interesting associations with the current models C. elegans and D. melanogaster.


Assuntos
Modelos Animais , Tardígrados/citologia , Animais , Caenorhabditis elegans , Desidratação , Drosophila melanogaster
16.
Adv Clin Exp Med ; 28(10): 1393-1401, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31518496

RESUMO

BACKGROUND: Cyclosporine-A (CsA) is widely used for immunosuppressive therapy in renal transplantation. Nephrotoxicity is the main dose-limiting undesirable consequence of CsA. Urotensin II (U-II), a novel peptide with a powerful influence on vascular biology, has been added to the list of potential renal vascular regulators. Upregulation of the urotensin receptors and elevation of plasma U-II levels are thought to possibly play a role in the etiology of renal failure. OBJECTIVES: The present study examines this hypothesis by evaluating renal function and histology with regard to the potential role of U-II and its antagonist, palosuran, in the pathogenesis of CsA-induced nephrotoxicity in rats. MATERIAL AND METHODS: Male Sprague-Dawley rats were treated with CsA (15 mg/kg, for 21 days, intraperitoneally) or CsA + palosuran (300 mg/kg, for 21 days). Renal function was measured and histopathology, U-II immunostaining and protein detection with western blotting of the kidneys were performed. RESULTS: Cyclosporine-A administration caused a marked decline in creatinine clearance (Ccr). Fractional sodium excretion (FENa) tended to increase in the CsA-treated rats. Plasma U-II levels decreased in the CsA-treated rats. Cyclosporine-A treatment resulted in a marked deterioration in renal histology and an increase in the expression of U-II protein in the kidneys. Palosuran's improvement of renal function manifested as a significant decrease in serum creatinine levels and a significant increase in urine creatinine levels, resulting in a marked increase in Ccr. Palosuran produced a significant normalization of kidney histology and prevented an increase in U-II expression. CONCLUSIONS: Cyclosporine-A-induced renal impairment was accompanied by an increase in U-II expression in kidneys and a contrary decrease in systemic U-II levels. Palosuran improved the condition of rats suffering from renal dysfunction by preventing the decrease in renal U-II expression without affecting the systemic levels of U-II. The protective effect of palosuran in CsA nephrotoxicity is possibly independent of its U-II receptor antagonism.


Assuntos
Ciclosporina/toxicidade , Nefropatias/tratamento farmacológico , Rim/efeitos dos fármacos , Urotensinas/antagonistas & inibidores , Animais , Creatinina/sangue , Creatinina/urina , Ciclosporina/efeitos adversos , Imunossupressores , Rim/metabolismo , Rim/patologia , Nefropatias/induzido quimicamente , Nefropatias/metabolismo , Masculino , Modelos Animais , Quinolinas , Ratos , Ratos Sprague-Dawley , Ratos Wistar , Ureia/análogos & derivados
17.
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue ; 31(8): 930-932, 2019 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-31537213

RESUMO

OBJECTIVE: Preclinical animal studies precede the majority of clinical trials. While the clinical definitions of sepsis and recommended treatments are regularly updated, a systematic review of preclinical models of sepsis has not been done and clear modeling guidelines are lacking. To address this deficit, a Wiggers-Bernard Conference on preclinical sepsis modeling was held in Vienna in May, 2017. The goal of the conference was to identify limitations of preclinical sepsis models and to propose a set of guidelines, defined as the "Minimum Quality Threshold in Pre-clinical Sepsis Studies" (MQTiPSS), to enhance translational value of these models. A total of 31 experts from 13 countries participated and were divided into six thematic Working Groups: Study Design, Humane modeling, Infection types, Organ failure/dysfunction, Fluid resuscitation, and Antimicrobial therapy endpoints. As basis for the MQTiPSS discussions, the participants conducted a literature review of the 260 most highly cited scientific articles on sepsis models (2003-2012). Overall, the participants reached consensus on 29 points; 20 at "recommendation" and nine at "consideration" strength. This Executive Summary provides a synopsis of the MQTiPSS consensus. We believe that these recommendations and considerations will serve to bring a level of standardization to preclinical models of sepsis and ultimately improve translation of preclinical findings. These guideline points are proposed as "best practices" for animal models of sepsis that should be implemented. To encourage its wide dissemination, this article is freely accessible on the Intensive Care Medicine Experimental and Infection journal websites. In order to encourage its wide dissemination, this article is freely accessible in Shock, Infection, and Intensive Care Medicine Experimental.


Assuntos
Sepse , Animais , Antibacterianos , Consenso , Cuidados Críticos , Hidratação , Humanos , Modelos Animais
18.
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue ; 31(8): 994-997, 2019 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-31537226

RESUMO

OBJECTIVE: To establish septic myocardial inhibition rat model by echocardiography. METHODS: Twenty adult male Sprague-Dawley (SD) rats were divided into control group and model group according to the random number table method, with 10 rats in each group. The rat model of septic myocardial inhibition was reproduced by intraperitoneal injection of 10 mg/kg lipopolysaccharide, while the control group was given the same volume of saline. The left ventricular end-diastolic diameter (LVDd), left ventricular end-diastolic volume (LVEDV), left ventricular end-systolic diameter (LVDs), left ventricular end-systolic volume (LVESV), left ventricular ejection fraction (LVEF), right ventricular end-diastolic diameter (RVDd), right ventricular end-systolic diameter (RVDs), heart rate (HR), positive pulmonary artery flow rate and aortic flow rate were measured at 8 hours after model establishment by echocardiography. Then the rats were sacrificed to harvest serum and myocardial tissue. The levels of serum tumor necrosis factor-α (TNF-α), nuclear factor-ΚB (NF-ΚB), interleukin-1 (IL-1), cardiac troponin I (cTnI) and B-type brain natriuretic peptide (BNP) were measured by enzyme linked immunosorbent assay (ELISA). The mRNA expressions of TNF-α, IL-1 and NF-ΚB in myocardium were detected by real-time polymerase chain reaction (real-time PCR). The pathological changes of myocardium were observed by hematoxylin-eosin (HE) staining under light microscope. RESULTS: Compared with control group, myocardial inhibition was obviously observed in model group, manifesting as enlargement of overall shape of heart, and prominent increase of HR (bpm: 449.0±21.1 vs. 356.7±23.3, P < 0.01); left ventricular and right ventricular functions were affected, LVDd, LVDs, LVEDV, LVESV were enlarged [LVDd (mm): 10.03±0.95 vs. 7.04±0.71, LVDs (mm): 5.95±0.71 vs. 3.07±0.05, LVEDV (mL): 2.11±0.53 vs. 0.81±0.21, LVESV (mL): 0.51±0.16 vs. 0.07±0.01, all P < 0.05], LVEF was significantly decreased (0.760±0.046 vs. 0.901±0.025, P < 0.01), RVDd was significantly increased (mm: 4.48±0.58 vs. 3.22±0.20, P < 0.05), and positive pulmonary artery velocity was significantly decreased (cm/s: 64.2±9.3 vs. 89.0±0.8, P < 0.05). Compared with control group, the levels of serum NF-ΚB, TNF-α, IL-1, BNP and cTnI in model group were significantly increased [NF-ΚB (ng/L): 103.84±6.55 vs. 57.29±41.34, TNF-α (ng/L): 1 198.32±164.07 vs. 835.45±24.01, IL-1 (ng/L): 1 089.90±221.96 vs. 746.19±165.83, BNP (ng/L): 1 097.36±293.84 vs. 454.71±197.79, cTnI (ng/L): 6 938.59±1 400.21 vs. 3 731.90±1 349.31, all P < 0.01], the mRNA expressions of TNF-α, NF-ΚB and IL-1 in myocardial tissue were significantly increased (2-ΔΔCT: 1.50±0.42 vs. 0.71±0.40, 1.10±0.17 vs. 0.63±0.06, 1.77±0.67 vs. 0.10±0.03, all P < 0.05). It was shown by HE staining that the structure of myocardial tissue in control group was distinct, the arrangement of myocardial fibers was neat, and transverse was clear; the structure of myocardial tissue in model group was loose, blurred, and the cells were swollen, with obvious pathological changes. CONCLUSIONS: Cardiac function was assessed by echocardiography, expression of inflammatory factors, myocardial markers and pathological changes. It was verified that intraperitoneal injection of 10 mg/kg endotoxin could successfully prepare a rat model of septic myocardial inhibition.


Assuntos
Endotoxinas/toxicidade , Injeções Intraperitoneais , Modelos Animais , Miocárdio , Animais , Masculino , NF-kappa B , Ratos , Ratos Sprague-Dawley , Fator de Necrose Tumoral alfa/sangue
19.
Braz Oral Res ; 33: e086, 2019 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-31483052

RESUMO

Treatment of patients with bisphosphonate usage is a significant concern for oral surgeons because it interferes with jaw bone turnover and regeneration. In case of adverse effects manifesting related to bisphosphonate use, oral surgeons are usually treating and keep the patient's symptoms under control. In this study, we aimed to investigate a new treatment protocol for medication-related osteonecrosis of the jaw (MRONJ). This treatment protocol consisted of administering human parathyroid hormone (hPTH) loaded chitosan microspheres which were prepared by ionotropic gelation method or/and the prepared microspheres were suspended in a poloxamer gel. After in-vitro optimization studies, the efficacy of the chosen formulations was evaluated in-vivo studies. Zoledronic acid was administered daily to forty-eight adult female Sprague-Dawley rats, divided into four experimental groups, at a daily concentration of 0.11 mg/kg over three weeks to induce the MRONJ model. At the end of this period, maxillary left molar teeth were extracted. In the first group, the subjects received no treatment. In the negative control group, poloxamer hydrogel containing empty microspheres were immediately applied to the soft tissues surrounding the extraction socket. The treatment group-1 was treated with local injections of poloxamer hydrogel containing hPTH. The treatment group-2 was treated with a single local injection of poloxamer hydrogel containing hPTH-loaded chitosan microspheres. Both treatment groups received a total of 7 µg of hPTH at the end of the treatment protocol. Our study demonstrates successful attenuation of MRONJ through a local drug delivery system combined with hPTH, as opposed to previously attempted treatment strategies.


Assuntos
Conservadores da Densidade Óssea/farmacologia , Quitosana/farmacologia , Maxila/efeitos dos fármacos , Hormônio Paratireóideo/farmacologia , Animais , Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/tratamento farmacológico , Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/etiologia , Conservadores da Densidade Óssea/efeitos adversos , Conservadores da Densidade Óssea/uso terapêutico , Quitosana/uso terapêutico , Preparações de Ação Retardada , Feminino , Humanos , Maxila/patologia , Microesferas , Modelos Animais , Hormônio Paratireóideo/uso terapêutico , Poloxâmero/administração & dosagem , Poloxâmero/química , Ratos Sprague-Dawley , Ácido Zoledrônico/efeitos adversos
20.
Adv Gerontol ; 32(3): 331-337, 2019.
Artigo em Russo | MEDLINE | ID: mdl-31512418

RESUMO

Aging of extracellular proteins colloidal systems is one of major synchronizing mechanism in mammal`s «biological clock¼. We hypothesized that induced controllable modification of connective tissue composition could reverse aging. In murine experimental models collagenase was used for selective destruction of old collagen. Oxygen consumption, urine hydroxyproline excretion, density and distribution of mature and old collagen and elastine fibers in dermal biopsies were determined. Collagenase injections significantly increased hydroxyproline excretion. We observed reduced density of mature and old collagen fibers and increased oxygen consumption in dermal biopsies after course of collagenase injections. Collagenase treatment intensified the destruction of mature and old collagen matrix and enhanced synthesis of new collagen and elastine fibers. Furthermore oxygen consumption increased. Our findings can be considered as indicator of collagenase systemic anti-aging (rejuvenation) activity.


Assuntos
Envelhecimento , Colágeno , Envelhecimento/efeitos dos fármacos , Animais , Colágeno/metabolismo , Colagenases/farmacologia , Hidroxiprolina/metabolismo , Camundongos , Modelos Animais , Consumo de Oxigênio/efeitos dos fármacos , Pele/efeitos dos fármacos
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