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1.
J Anat ; 243(3): 486-503, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37042468

RESUMO

Sea turtles use olfaction to detect volatile and water-soluble substances. The nasal cavity of green turtles (Chelonia mydas) comprises morphologically defined the anterodorsal, anteroventral, and posterodorsal diverticula, as well as a single posteroventral fossa. Here, we detailed the histological features of the nasal cavity of a mature female green turtle. The posterodorsal diverticulum contained spongy-like venous sinuses and a wave-shaped sensory epithelium that favored ventilation. Secretory structures that were significant in sensory and non-sensory epithelia were probably involved in protection against seawater. These findings suggested that green turtles efficiently intake airborne substances and dissolve water-soluble substances in mucous, while suppressing the effects of salts. In addition, positive staining of Gαs/olf that couples with olfactory, but not vomeronasal, receptors was predominant in all three types of sensory epithelium in the nasal cavity. Both of airborne and water-soluble odorants seemed to be detected in cells expressing Gαolf and olfactory receptors.


Assuntos
Neurônios Receptores Olfatórios , Receptores Odorantes , Tartarugas , Animais , Feminino , Cavidade Nasal , Tartarugas/anatomia & histologia , Epitélio
2.
Physiol Plant ; 175(3): e13940, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37253942

RESUMO

Grape compound buds adapt to subfreezing temperatures in winter by supercooling, but the supercooling ability is thought to be lost upon formation of xylem connections between canes and buds. It was reported that compound buds of the Vitis vinifera variety 'Chardonnay' lack xylem cells in mid-winter, and that vessels differentiate during deacclimation. However, the pattern of vessel formation in compound buds may differ in cold-hardy Vitis species and interspecific hybrid varieties grown in colder regions. We investigated vessel formation in compound buds of the interspecific hybrid variety 'Yamasachi', which were harvested in mid-winter, during artificial deacclimation treatments. Before these treatments, 'Yamasachi' buds had a high supercooling ability (approx. -30°C) and contained cells with characteristics of vessel elements, that is, secondary wall thickening and lignification, at the basal parts. However, the cells still contained organelles and did not have a hydraulic conductivity function. Xylem continuity between the canes and buds was established from day 7 of deacclimation at 20°C. The different pattern of seasonal vessel formation in compound buds of 'Yamasachi' from that of V. vinifera may reflect the rapid development traits of Vitis species growing in cold regions with short growing seasons.


Assuntos
Vitis , Temperatura Baixa , Temperatura , Xilema , Estações do Ano
3.
J Anat ; 241(3): 809-819, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35437747

RESUMO

In contrast to the main olfactory system that detects volatile chemicals in the nasal air, the vomeronasal system can detect nonvolatile chemicals as well as volatiles. In the vomeronasal system, chemicals are perceived by the vomeronasal organ (VNO) projecting axons to the accessory olfactory bulb (AOB). Beavers (Castor spp.) are semiaquatic mammals that have developed chemical communication. It is possible that the beaver's anal gland secretions, nonvolatile and insoluble substances, may work as a messenger in the water and that beavers may detect the nonvolatile chemicals floating on the water surface via the VNO. The present study aimed to clarify the specificities of the beaver vomeronasal system by histologically and immunohistochemically analyzing the VNO and AOB of 12 Eurasian beavers (C. fiber). The VNO directly opened to the nasal cavity and was independent of a narrow nasopalatine duct connecting the oral and nasal cavities. The VNO comprised soft tissues including sensory and nonsensory epithelium, glands, a venous sinus, an artery, as well as cartilage inner, and bone outer enclosures. The AOB had distinct six layers, and anti-G protein α-i2 and α-o subunits were, respectively, immunoreactive in rostral and caudal glomeruli layers indicating expressions of V1Rs and V2Rs. According to gene repertories analysis, the beavers had 23 and six intact V1R and V2R genes respectively. These findings suggested that beavers recognize volatile odorants and nonvolatile substances using the vomeronasal system. The beaver VNO was developed as well as in other rodents, and it had two specific morphological features, namely, disadvantaged contact with the oral cavity because of a tiny nasopalatine duct, and a double bone and cartilage envelope. Our results highlight the importance of the vomeronasal system in beaver chemical communication and support the possibility that beavers can detect chemicals floating on the water surface via the VNO.


Assuntos
Órgão Vomeronasal , Animais , Bulbo Olfatório/metabolismo , Roedores , Órgão Vomeronasal/anatomia & histologia , Água/análise , Água/metabolismo
4.
Neuropathology ; 42(1): 16-27, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34957592

RESUMO

Normal-pressure hydrocephalus (NPH) is a condition in which the ventricle is enlarged without elevated cerebrospinal fluid pressure, and it generally develops in later life and progresses slowly. A complete animal model that mimics human idiopathic NPH has not yet been established, and the onset mechanisms and detailed pathomechanisms of NPH are not fully understood. Here, we demonstrate a high spontaneous prevalence (34.6%) of hydrocephalus without clinical symptoms in inbred cotton rats (Sigmodon hispidus). In all 46 hydrocephalic cotton rats, the severity was mild or moderate and not severe. The dilation was limited to the lateral ventricles, and none of the hemorrhage, ventriculitis, meningitis, or tumor formation was found in hydrocephalic cotton rats. These findings indicate that the type of hydrocephalus in cotton rats is similar to that of communicating idiopathic NPH. Histopathological examinations revealed that the inner granular and pyramidal layers (layers IV and V) of the neocortex became thinner in hydrocephalic brains. A small number of pyramidal cells were positive for Fluoro-Jade C (a degenerating neuron marker) and ionized calcium-binding adaptor molecule 1 (Iba1)-immunoreactive microglia were in contact with the degenerating neurons in the hydrocephalic neocortex, suggesting that hydrocephalic cotton rats are more or less impaired projections from the neocortex. This study highlights cotton rats as a candidate for novel models to elucidate the pathomechanism of idiopathic NPH. Additionally, cotton rats have some noticeable systemic pathological phenotypes, such as chronic kidney disease and metabolic disorders. Thus, this model might also be useful for researching the comorbidities of NPH to other diseases.


Assuntos
Hidrocefalia de Pressão Normal , Hidrocefalia , Animais , Encéfalo , Ventrículos Cerebrais , Prevalência , Sigmodontinae
5.
Parasitol Res ; 121(1): 413-422, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34750652

RESUMO

The natural polyether ionophore antibiotics may be important chemotherapeutic agents. Among them, kijimicin represents an important type of ionophore compound because it inhibits Eimeria tenella and human immunodeficiency virus. The ionophore monensin displays potent activities against several coccidian parasites including the opportunistic pathogen of humans, Toxoplasma gondii. At first, we evaluated the anti-Toxoplasma activity of kijimicin, monensin as a reference control, and anti-Toxoplasma drugs such as clindamycin, in vitro. The half inhibitory concentrations (IC50) for the anti-Toxoplasma activities of kijimicin, monensin, and clindamycin were 45.6 ± 2.4 nM, 1.3 ± 1.8 nM, and 238.5 ± 1.8 nM, respectively. Morphological analyses by electron microscopy revealed cellular swelling and multiple intracellular vacuole-like structures in the T. gondii tachyzoites after treatment with kijimicin and monensin. Kijimicin and monensin also inhibited the invasion of extracellular parasites (IC50 = 216.6 ± 1.9 pM and 531.1 ± 1.9 pM, respectively). Importantly, kijimicin treatment resulted in decreased mitochondrial membrane potential and generation of reactive oxygen species in T. gondii as monensin did. Furthermore, mice treated with kijimicin at 10 mg/kg/day and 3 mg/kg/day showed 91.7% and 66.7% survival rates, respectively, 30 days after infection with T. gondii. The control mice all died within 18 days of infection. The present study shows that kijimicin inhibits T. gondii growth and changes the ultrastruct of the parasites. This finding may lead to validation of kijimicin as new drug to control T. gondii growth.


Assuntos
Toxoplasma , Toxoplasmose , Animais , Ionóforos , Camundongos , Piranos
6.
Antimicrob Agents Chemother ; 65(7): e0020421, 2021 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-33941516

RESUMO

Due to drug resistance, commonly used anti-Babesia drugs have limited efficacy against babesiosis and inflict severe side effects. Tafenoquine (TAF) was approved by the U.S. Food and Drug Administration in 2018 for the radical cure of Plasmodium vivax infection and for malaria prophylaxis. Here, we evaluated the efficacy of TAF for the treatment of Babesia infection and elucidated the suspected mechanisms of TAF activity against Babesia parasites. Parasitemia and survival rates of Babesia rodhaini-infected BALB/c and SCID mice were used to explore the role of the immune response in Babesia infection after TAF treatment. Parasitemia, survival rates, body weight, vital signs, complete blood count, and blood biochemistry of B. gibsoni-infected splenectomized dogs were determined to evaluate the anti-Babesia activity and side effects of TAF. Then, to understand the mechanism of TAF activity, hydrogen peroxide was used as an oxidizer for short-term B. rodhaini incubation in vitro, and the expression levels of antioxidant enzymes were confirmed using B. microti-infected mice by reverse transcription-quantitative PCR (qRT-PCR). Acute B. rodhaini and B. gibsoni infections were rapidly eliminated with TAF administration. Repeated administration of TAF or a combination therapy with other antibabesial agents is still needed to avoid a potentially fatal recurrence for immunocompromised hosts. Caution about hyperkalemia should be taken during TAF treatment for Babesia infection. TAF possesses a babesicidal effect that may be related to drug-induced oxidative stress. Considering the lower frequency of glucose-6-phosphate dehydrogenase deficiency in animals compared to that in humans, TAF use on Babesia-infected farm animals and pets is eagerly anticipated.


Assuntos
Babesiose , Preparações Farmacêuticas , Aminoquinolinas , Animais , Babesiose/tratamento farmacológico , Cães , Camundongos , Camundongos Endogâmicos BALB C , Camundongos SCID
7.
Cell Tissue Res ; 383(1): 347-352, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33404839

RESUMO

The nasal cavity of tetrapods has become phylogenetically adapted to the environment in terms of function, respiration, and olfaction. In addition, the nasal cavity of sea turtles plays an important role in seawater flow and water olfaction, unlike that of terrestrial species. Here, we describe the functional, morphological, and histological characteristics of the nasal cavity, and the odorant receptors encoded in the genome of sea turtles. The nasal cavity of sea turtles is well-suited to its complicated functions, and it significantly differs from those of other animals, including terrestrial and semi-aquatic turtles.


Assuntos
Cavidade Nasal/fisiologia , Olfato/fisiologia , Animais , Água do Mar , Tartarugas
8.
Cell Tissue Res ; 386(2): 391-413, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34319433

RESUMO

All animals, other than Platyhelminthes, produce eggs containing yolk, referred to as "entolecithal" eggs. However, only Neoophora, in the phylum Platyhelminthes, produce "ectolecithal" eggs (egg capsules), in which yolk is stored in the vitelline cells surrounding oocytes. Vitelline cells are derived from vitellaria (yolk glands). Vitellaria are important reproductive organs that may be studied to elucidate unique mechanisms that have been evolutionarily conserved within Platyhelminthes. Currently, only limited molecular level information is available on vitellaria. The current study identified major vitellaria-specific proteins in a freshwater planarian, Dugesia ryukyuensis, using peptide mass fingerprinting (PMF) and expression analyses. Amino acid sequence analysis and orthology analysis via OrthoFinder ver.2.3.8 indicated that the identified major vitellaria-specific novel yolk ferritins were conserved in planarians (Tricladida). Because ferritins play an important role in Fe (iron) storage, we examined the metal elements contained in vitellaria and ectolecithal eggs, using non-heme iron histochemistry, elemental analysis based on inductively coupled plasma mass spectrometry and transmission electron microscopy- energy-dispersive X-ray spectroscopy analysis. Interestingly, vitellaria and egg capsules contained large amounts of aluminum (Al), but not Fe. The knockdown of the yolk ferritin genes caused a decrease in the volume of egg capsules, abnormality in juveniles, and increase in Al content in vitellaria. Yolk ferritins of D. ryukyuensis may regulate Al concentration in vitellaria via their pooling function of Al and protect the egg capsule production and normal embryogenesis from Al toxicity.


Assuntos
Alumínio/metabolismo , Proteínas do Ovo/metabolismo , Ferritinas/metabolismo , Proteínas de Helminto/metabolismo , Ferro/metabolismo , Planárias/metabolismo , Sequência de Aminoácidos , Animais , Proteínas do Ovo/análise , Proteínas do Ovo/genética , Ferritinas/análise , Ferritinas/genética , Proteínas de Helminto/análise , Proteínas de Helminto/genética , Óvulo/crescimento & desenvolvimento , Óvulo/metabolismo , Planárias/genética , Planárias/crescimento & desenvolvimento
9.
J Infect Dis ; 221(5): 766-774, 2020 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-31573038

RESUMO

BACKGROUND: Toxoplasmosis, a parasitic disease caused by Toxoplasma gondii, is an important cause of miscarriage or adverse fetal effects, including neurological and ocular manifestations in humans. Current anti-Toxoplasma drugs have limited efficacy against toxoplasmosis and also have severe side effects. Therefore, novel efficacious drugs are urgently needed. Here, we identified metacytofilin (MCF) from a fungal Metarhizium species as a potential anti-Toxoplasma compound. METHODS: Anti-Toxoplasma activities of MCF and its derivatives were evaluated in vitro and in vivo using nonpregnant and pregnant mice. To understand the mode of action of MCF, the RNA expression of host and parasite genes was investigated by RNAseq. RESULTS: In vitro, MCF inhibited the viability of intracellular and extracellular T. gondii. Administering MCF intraperitoneally or orally to mice after infection with T. gondii tachyzoites increased mouse survival compared with the untreated animals. Remarkably, oral administration of MCF to pregnant mice prevented vertical transmission of the parasite. Interestingly, RNA sequencing of T. gondii-infected cells treated with MCF showed that MCF inhibited DNA replication and enhanced RNA degradation in the parasites. CONCLUSIONS: With its potent anti-T. gondii activity, MCF is a strong candidate for future drug development against toxoplasmosis.


Assuntos
Antiparasitários/uso terapêutico , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Oxazinas/uso terapêutico , Toxoplasma/efeitos dos fármacos , Toxoplasmose/tratamento farmacológico , Toxoplasmose/mortalidade , Administração Intravenosa , Administração Oral , Animais , Antiparasitários/administração & dosagem , Antiparasitários/farmacologia , Replicação do DNA/efeitos dos fármacos , DNA de Protozoário , Modelos Animais de Doenças , Feminino , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Oxazinas/administração & dosagem , Oxazinas/farmacologia , Gravidez , Taxa de Sobrevida , Toxoplasma/genética , Toxoplasmose/parasitologia , Toxoplasmose/transmissão , Resultado do Tratamento
10.
Vet Res ; 51(1): 119, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32933583

RESUMO

Lesions of adiaspiromycosis, a respiratory disease affecting wild animals, have been found mainly in dead mammals and free-living mammals captured for surveillance. No report has described an investigation of adiaspore formation progress in the lung. After establishing an experimental mouse model of intratracheal adiaspiromycosis infection with the causative agent Emmonsia crescens, we observed adiaspore development. The spores grew and reached a plateau of growth at 70 days post-infection. The median adiaspore diameter showed a plateau of around 40 µm. The characteristic three-layer cell-wall structure of adiaspores was observed in the lung at 70 days post-infection. We examined infection with a few spores, which revealed that adiaspores in the mouse lung progressed from intratracheal infection of at least 400 spores. Moreover, we developed adiaspores in vitro by culture in fetal bovine serum. Although most spores broke, some large spores were intact. They reached about 50 µm diameter. Thick cell walls and dense granules were found as common points between in vitro adiaspores and in vivo adiaspores. These models are expected to be useful for additional investigations of E. crescens adiaspores and adiaspiromycosis.


Assuntos
Chrysosporium/fisiologia , Pneumopatias Fúngicas/veterinária , Esporos Fúngicos/fisiologia , Animais , Chrysosporium/crescimento & desenvolvimento , Chrysosporium/ultraestrutura , Modelos Animais de Doenças , Pneumopatias Fúngicas/microbiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microscopia/veterinária , Microscopia Eletrônica de Transmissão/veterinária , Esporos Fúngicos/crescimento & desenvolvimento , Esporos Fúngicos/ultraestrutura
11.
Chem Senses ; 44(7): 427-434, 2019 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-31155674

RESUMO

The morphological and histological features of the nasal cavity are diverse among animal species, and the nasal cavities of terrestrial and semiaquatic turtles possess 2 regions lined with each different type of sensory epithelium. Sea turtles can inhale both of volatile and water-soluble odorants with high sensitivity, but details of the architectural features and the distribution of the sensory epithelia within the sea turtle nasal cavity remain uncertain. The present study analyzed the nasal cavity of green sea turtles using morphological, computed tomographic, and histological methods. We found that the middle region of the sea turtle nasal cavity is divided into anterodorsal, anteroventral, and posterodorsal diverticula and a posteroventral excavation by connective tissue containing cartilages. The posterodorsal diverticulum was lined with a thin sensory epithelium, and the anterodorsal and anteroventral diverticula were occupied by a single thick sensory epithelium. In addition, a relatively small area on the posteroventral excavation was covered by independent sensory epithelium that differed from other 2 types of epithelia, and a single thin bundle derived from the posteroventral excavation comprised the most medial nerve that joins the anterior end of the olfactory nerve tract. These findings suggested that the posteroventral excavation identified herein transfers stimuli through an independent circuit and plays different roles when odorants arise from other nasal regions.


Assuntos
Epitélio/fisiologia , Cavidade Nasal/fisiologia , Mucosa Nasal/fisiologia , Animais , Odorantes/análise , Tartarugas
12.
Exp Parasitol ; 199: 40-46, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30840850

RESUMO

Human African trypanosomosis (HAT) and animal African trypanosomosis (AAT) are diseases of economic importance in humans and animals that affect more than 36 African countries. The currently available trypanocidal drugs are associated with side effects, and the parasites are continually developing resistance. Thus, effective and safe drugs are needed for the treatment of HAT and AAT. This study aimed to evaluate the effects of azithromycin (AZM) on Trypanosoma brucei brucei-infected mice. Mice were randomly divided into 7 groups consisting of a vehicle control group, 5 test groups and a diminazene aceturate (DA)-treated group. Mice were treated orally for 7 and 28 days, as short-term and long-term treatments, respectively. Short-term AZM treatment cured 23% (16 of 70) of the overall treated mice whereas long-term treatment resulted in the survival of 70% of the mice in the groups that received AZM at doses of 300 and 400 mg/kg. Trypanosomes treated in vitro with 25 µg/mL of AZM were subjected to transmission electron microscopy, which revealed the presence of increased numbers of glycosomes and acidocalcisomes in comparison to the vehicle group. The current study showed the trypanocidal effect of AZM on T. b. brucei in vivo. The demonstrated efficacy increased with an increase in treatment period and an increased concentration of AZM.


Assuntos
Anti-Infecciosos/administração & dosagem , Azitromicina/administração & dosagem , Trypanosoma brucei brucei/efeitos dos fármacos , Tripanossomíase Africana/tratamento farmacológico , Administração Oral , Animais , Anti-Infecciosos/farmacologia , Anti-Infecciosos/uso terapêutico , Azitromicina/farmacologia , Azitromicina/uso terapêutico , Peso Corporal/efeitos dos fármacos , Feminino , Concentração Inibidora 50 , Camundongos , Camundongos Endogâmicos C57BL , Microscopia Eletrônica de Transmissão , Parasitemia/tratamento farmacológico , Distribuição Aleatória , Taxa de Sobrevida , Fatores de Tempo , Trypanosoma brucei brucei/ultraestrutura , Tripanossomíase Africana/mortalidade
13.
Parasitol Res ; 118(6): 1927-1935, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31055671

RESUMO

Trypanosoma (Megatrypanum) theileri is a cosmopolitan, usually non-pathogenic, trypanosome of cattle transmitted by blood-sucking arthropods, mainly tabanid flies. Several T. theileri strains isolated from domestic and wild ruminants via co-culturing with mammalian feeder cells or blood cells have been characterized morphologically and genetically. Here, we cultured a new trypanosome isolate from a Holstein cow in Hokkaido, Japan, and performed morphological and molecular characterization studies. The new isolate (Obihiro strain) was co-cultivated with Madin-Darby bovine kidney (MDBK) cells in GIT medium supplemented with 10% fetal bovine serum. Trypomastigotes and epimastigotes, but not intracellular parasites, were identified in the culture. Analysis of the V7-V8 region of 18S rRNA sequences showed that the Obihiro strain is positioned within the subgenus Megatrypanum. A dendrogram based on whole internal transcribed spacer rDNA sequence showed that the Obihiro strain clustered in the lineage TthII together with the Japanese isolates of T. theileri, Esashi 9, and Esashi 12, and isolates from Zambia and the USA. T. theileri of the KM strain and a T. theileri-like trypanosome isolated from deer (TSD1 strain) clustered in the lineage TthI, separate from the Obihiro strain. Based on a partial cathepsin L-like protein gene analysis, the Obihiro strain clustered with isolates of the TthIIF genotype, which includes T. theileri from Vietnam, Sri Lanka, and Brazil. Our analyses of the T. theileri Obihiro strain provide relevant insights into its genetic diversity in Japanese cattle and corroborate the host specificity of cattle and deer trypanosomes of the subgenus Megatrypanum.


Assuntos
Doenças dos Bovinos/parasitologia , Trypanosoma/classificação , Trypanosoma/genética , Tripanossomíase/veterinária , Animais , Catepsina L/genética , Bovinos , Linhagem Celular , DNA Ribossômico/genética , DNA Espaçador Ribossômico/genética , Cervos/parasitologia , Feminino , Genótipo , Especificidade de Hospedeiro , Japão , Filogenia , RNA Ribossômico 18S/genética , Trypanosoma/isolamento & purificação , Tripanossomíase/parasitologia
14.
Cell Tissue Res ; 373(2): 361-366, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29552725

RESUMO

Receptor cells of the olfactory epithelium (OE) and vomeronasal organ (VNO) project axons to glomeruli in the main olfactory bulb (MOB) and accessory olfactory bulb (AOB), respectively and undergo continuous turnover throughout life. Alpha1-2 fucose (α1-2Fuc) glycan mediates neurite outgrowth and synaptic plasticity and plays important roles in the formation of the olfactory system during development. We previously confirmed the localization of α1-2Fuc glycan in the olfactory system of 3- to 4-month-old mice but whether such localization persists throughout life remains unknown. Here, the MOB, AOB, OE and VNO of 1-, 3- and 8-month-old mice were histochemically examined using Ulex europaeus agglutinin-I (UEA-I) that specifically binds to α1-2Fuc glycan. Binding sites for UEA-I in the MOB were similar among all age groups but the ratio of UEA-I-positive glomeruli significantly decreased with aging. The frequency of UEA-I-positive receptor cells in the OE of the two older groups was also significantly lower than that of 1-month-old mice. On the other hand, UEA-I binding in the AOB and VNO did not significantly differ among all three groups. These findings suggest that the primary pathway of the main olfactory system requires the role of α1-2Fuc glycan in young mice rather than old mice, while the vomeronasal pathway equally requires this glycan in both young and old mice.


Assuntos
Fucose/metabolismo , Bulbo Olfatório/metabolismo , Mucosa Olfatória/metabolismo , Órgão Vomeronasal/metabolismo , Fatores Etários , Animais , Lectinas/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos ICR , Bulbo Olfatório/ultraestrutura , Mucosa Olfatória/ultraestrutura , Lectinas de Plantas/farmacologia , Estatísticas não Paramétricas , Órgão Vomeronasal/ultraestrutura
15.
J Anat ; 231(5): 749-757, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28786107

RESUMO

The vomeronasal organ (VNO) is a peripheral receptor structure that is involved in reproductive behavior and is part of the vomeronasal system. Male bears exhibit flehmen behavior that is regarded as the uptake of pheromones into the VNO to detect estrus in females. However, the morphological and histological features of the VNO in bears have not been comprehensively studied. The present study investigated the properties and degree of development of the VNO of the brown bear by histological, histochemical and ultrastructural methods. The VNO of bears was located at the same position as that of many other mammals, and it opened to the mouth like the VNO of most carnivores. The shape of the vomeronasal cartilages and the histological features of the sensory epithelium in the bear VNO were essentially similar to those of dogs. Receptor cells in the VNO of the bear possessed both cilia and microvilli like those of dogs. The dendritic knobs of receptor cells were positive for anti-G protein alpha-i2 subunit (Gαi2 ) but negative for anti-G protein alpha-o subunit, indicating preferential use of the V1R-Gαi2 pathway in the vomeronasal system of bears, as in other carnivores. The VNO of the bear possessed three types of secretory cells (secretory cells of the vomeronasal gland, multicellular intraepithelial gland cells and goblet cells), and the present findings showed that the secretory granules in these cells also had various properties. The vomeronasal lumen at the middle region of the VNO invaginated toward the ventral region, and this invagination contained tightly packed multicellular intraepithelial gland cells. To our knowledge, this invagination and intraepithelial gland masses in the VNO are unique features of brown bears. The VNO in the brown bear, especially the secretory system, is morphologically well-developed, suggesting that this organ is significant for information transmission in this species.


Assuntos
Ursidae/anatomia & histologia , Órgão Vomeronasal/anatomia & histologia , Animais , Feminino , Masculino
16.
Cells Tissues Organs ; 203(1): 20-28, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27423908

RESUMO

Glycoconjugates in the olfactory system play critical roles in neuronal formation, and α1-2 fucose (α1-2Fuc) glycan mediates neurite outgrowth and synaptic plasticity. Histochemical findings of α1-2Fuc glycan in the mouse olfactory system detected using Ulex europaeus agglutinin-I (UEA-I) vary. This study histochemically assessed the main olfactory and vomeronasal pathways in male and female ICR and C57BL/6J mice aged 3-4 months using UEA-I. Ulex europaeus agglutinin-I reacted with most receptor cells arranged mainly at the basal region of the olfactory epithelium. The olfactory nerve layer and glomerular layer of the main olfactory bulb were speckled with positive UEA-I staining, and positive fibers were scattered from the glomerular to the internal plexiform layer. The lateral olfactory tract and rostral migratory stream were also positive for UEA-I. We identified superficial short-axon cells, interneurons of the external plexiform layer, external, middle and internal tufted cells, mitral cells and granule cells as the origins of the UEA-I-positive fibers in the main olfactory bulb. The anterior olfactory nucleus, anterior piriform cortex and olfactory tubercle were negative for UEA-I. Most receptor cells in the vomeronasal epithelium and most glomeruli of the accessory olfactory bulb were positive for UEA-I. Our findings indicated that α1-2Fuc glycan is located within the primary and secondary, but not the ternary, pathways of the main olfactory system, in local circuits of the main olfactory bulb and within the primary, but not secondary, pathway of the vomeronasal system.


Assuntos
Fucose/metabolismo , Condutos Olfatórios/metabolismo , Lectinas de Plantas/metabolismo , Polissacarídeos/metabolismo , Animais , Feminino , Masculino , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos ICR , Bulbo Olfatório/metabolismo , Mucosa Olfatória/metabolismo , Órgão Vomeronasal/metabolismo
17.
Brain Behav Evol ; 90(3): 224-231, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28850945

RESUMO

The olfactory system of mammals comprises a main olfactory system that detects hundreds of odorants and a vomeronasal system that detects specific chemicals such as pheromones. The main (MOB) and accessory (AOB) olfactory bulbs are the respective primary centers of the main olfactory and vomeronasal systems. Most mammals including artiodactyls possess a large MOB and a comparatively small AOB, whereas most cetaceans lack olfactory bulbs. The common hippopotamus (Hippopotamus amphibius) is semiaquatic and belongs to the order Cetartiodactyla, family Hippopotamidae, which seems to be the closest extant family to cetaceans. The present study evaluates the significance of the olfactory system in the hippopotamus by histologically analyzing the MOB and AOB of a male common hippopotamus. The MOB comprised six layers (olfactory nerve, glomerular, external plexiform, mitral cell, internal plexiform, and granule cell), and the AOB comprised vomeronasal nerve, glomerular, plexiform, and granule cell layers. The MOB contained mitral cells and tufted cells, and the AOB possessed mitral/tufted cells. These histological features of the MOB and the AOB were similar to those in most artiodactyls. All glomeruli in the AOB were positive for anti-Gαi2, but weakly positive for anti-Gαo, suggesting that the hippopotamus vomeronasal system expresses vomeronasal type 1 receptors with a high affinity for volatile compounds. These findings suggest that the olfactory system of the hippopotamus is as well developed as that of other artiodactyl species and that the hippopotamus might depend on its olfactory system for terrestrial social communication.


Assuntos
Artiodáctilos/anatomia & histologia , Bulbo Olfatório/anatomia & histologia , Bulbo Olfatório/citologia , Animais , Masculino , Neurônios , Nervo Olfatório/fisiologia , Condutos Olfatórios/anatomia & histologia , Condutos Olfatórios/fisiologia , Olfato/fisiologia
18.
BMC Vet Res ; 13(1): 292, 2017 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-28962659

RESUMO

BACKGROUND: Laterality disorders of the abdominal organs include situs inversus totalis that mirrors the arrangements of all internal organs and heterotaxy syndrome (situs ambiguus) in which the thoracic or abdominal organs are abnormally arranged. Heterotaxy is often accompanied by multiple congenital malformations, and it generally comprises asplenia and polysplenia syndromes. To our knowledge, polysplenia syndrome has been reported in only three cattle, and computerized tomographic (CT) images of these animals were not obtained. CASE PRESENTATION: A six-month-old Holstein heifer had ruminal tympani and right abdominal distension. CT imaging showed that the rumen occupied the right side of the abdominal cavity, the omasum and abomasum occupied the left ventral side and the liver was positioned on the left. The colon and cecum were located at the left dorsum of the cavity, and the left kidney was located more cranially than the right. Postmortem findings revealed two spleens attached to the rumen. Significantly, the duodenum was too short to be divided into segments, except the cranial and descending parts, or flexures, except the cranial flexure, and the pancreas, which lacked a left lobe, was covered with mesojejunum. The liver comprised a relatively large right lobe and a small left lobe without quadrate and caudate lobes. The caudal vena cava that connected to the left azygous vein passed irregularly through the aortic hiatus of the diaphragm, and the common hepatic vein without the caudal vena cava passed through the caval foramen. Although the lungs and heart were morphologically normal, the right atrium received three major systemic veins. Polysplenia syndrome was diagnosed based on the CT and postmortem findings. CONCLUSION: We defined the positions of the abdominal organs and morphological abnormalities in various organs of a calf with polysplenia syndrome based on CT and postmortem findings. These findings will improve understanding of the malpositioning and malformations that can occur in the organs of cattle with polysplenia syndrome.


Assuntos
Anormalidades Múltiplas/veterinária , Bovinos/anormalidades , Duodeno/anormalidades , Síndrome de Heterotaxia/veterinária , Pâncreas/anormalidades , Baço/anormalidades , Anormalidades Múltiplas/diagnóstico por imagem , Animais , Duodeno/diagnóstico por imagem , Feminino , Síndrome de Heterotaxia/diagnóstico por imagem , Pâncreas/diagnóstico por imagem , Baço/diagnóstico por imagem , Síndrome , Tomografia Computadorizada por Raios X/veterinária
19.
J Biol Chem ; 289(52): 36158-65, 2014 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-25384980

RESUMO

The circadian clock regulates various behavioral and physiological rhythms in mammals. Circadian changes in olfactory functions such as neuronal firing in the olfactory bulb (OB) and olfactory sensitivity have recently been identified, although the underlying molecular mechanisms remain unknown. We analyzed the temporal profiles of glycan structures in the mouse OB using a high-density microarray that includes 96 lectins, because glycoconjugates play important roles in the nervous system such as neurite outgrowth and synaptogenesis. Sixteen lectin signals significantly fluctuated in the OB, and the intensity of all three that had high affinity for α1-2-fucose (α1-2Fuc) glycan in the microarray was higher during the nighttime. Histochemical analysis revealed that α1-2Fuc glycan is located in a diurnal manner in the lateral olfactory tract that comprises axon bundles of secondary olfactory neurons. The amount of α1-2Fuc glycan associated with the major target glycoprotein neural cell adhesion molecule (NCAM) varied in a diurnal fashion, although the mRNA and protein expression of Ncam1 did not. The mRNA and protein expression of Fut1, a α1-2-specific fucosyltransferase gene, was diurnal in the OB. Daily fluctuation of the α1-2Fuc glycan was obviously damped in homozygous Clock mutant mice with disrupted diurnal Fut1 expression, suggesting that the molecular clock governs rhythmic α1-2-fucosylation in secondary olfactory neurons. These findings suggest the possibility that the molecular clock is involved in the diurnal regulation of olfaction via α1-2-fucosylation in the olfactory system.


Assuntos
Antígeno CD56/metabolismo , Proteínas CLOCK/genética , Neurônios Receptores Olfatórios/metabolismo , Animais , Ritmo Circadiano , Fucose/metabolismo , Fucosiltransferases/genética , Fucosiltransferases/metabolismo , Expressão Gênica , Regulação da Expressão Gênica , Glicosilação , Masculino , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos ICR , Camundongos Transgênicos , Nervo Olfatório/citologia , Processamento de Proteína Pós-Traducional , Galactosídeo 2-alfa-L-Fucosiltransferase
20.
Infect Immun ; 83(1): 8-16, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25312951

RESUMO

In the present study, we examined the contributions of macrophages to the outcome of infection with Babesia microti, the etiological agent of human and rodent babesiosis, in BALB/c mice. Mice were treated with clodronate liposome at different times during the course of B. microti infection in order to deplete the macrophages. Notably, a depletion of host macrophages at the early and acute phases of infection caused a significant elevation of parasitemia associated with remarkable mortality in the mice. The depletion of macrophages at the resolving and latent phases of infection resulted in an immediate and temporal exacerbation of parasitemia coupled with mortality in mice. Reconstituting clodronate liposome-treated mice at the acute phase of infection with macrophages from naive mice resulted in a slight reduction in parasitemia with improved survival compared to that of mice that received the drug alone. These results indicate that macrophages play a crucial role in the control of and resistance to B. microti infection in mice. Moreover, analyses of host immune responses revealed that macrophage-depleted mice diminished their production of Th1 cell cytokines, including gamma interferon (IFN-γ) and tumor necrosis factor alpha (TNF-α). Furthermore, depletion of macrophages at different times exaggerated the pathogenesis of the infection in deficient IFN-γ(-/-) and severe combined immunodeficiency (SCID) mice. Collectively, our data provide important clues about the role of macrophages in the resistance and control of B. microti and imply that the severity of the infection in immunocompromised patients might be due to impairment of macrophage function.


Assuntos
Babesia microti/imunologia , Babesiose/imunologia , Macrófagos/imunologia , Animais , Antiprotozoários/uso terapêutico , Babesiose/tratamento farmacológico , Ácido Clodrônico/uso terapêutico , Citocinas/metabolismo , Feminino , Interferon gama/metabolismo , Camundongos Endogâmicos BALB C , Análise de Sobrevida , Células Th1/imunologia , Resultado do Tratamento
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