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1.
J Invertebr Pathol ; 203: 108043, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38104963

RESUMO

Three new aurantiactinomyxon types are described from the oligochaete Ilyodrilus templetoni (Southern, 1909) (Naididae) collected from a northern Portuguese estuary, based on light microscopy and sequencing of the 18S rDNA. The addition of I. templetoni to the group of freshwater annelids known to be permissive for aurantiactinomyxon development reinforces the crucial role of naidids in the evolution and settlement of myxozoans in estuarine environments. Maximum likelihood and Bayesian inference analyses of a comprehensive 18S rDNA dataset placed the novel types within the Paramyxidium clade. This positioning suggests them as probable life cycle counterparts to Paramyxidium spp. that most likely infect the European eel Anguilla anguilla, as the sole representative of Elopomorpha in Portuguese rivers. Although distance estimation revealed a genetic difference of only 0.4 % between Aurantiactinomyxon types 1 and 3, this value was determined to be representative of interspecific variability based on the consistent matching of both genotypes with distinct actinospore morphologies, and potential richness of closely related species of Paramyxidium infecting the European eel in Portuguese waters. The clustering of aurantiactinomyxon types within distinct myxosporean lineages, representative of the suborders Variisporina and Platysporina, demonstrates that the aurantiactinomyxon morphotype is highly functional in promoting myxozoan infections in estuarine environments.


Assuntos
Cnidários , Doenças do Cão , Doenças dos Peixes , Myxozoa , Oligoquetos , Cães , Animais , Myxozoa/genética , Cnidários/genética , Filogenia , Teorema de Bayes , DNA Ribossômico/genética , Oligoquetos/genética
2.
Zygote ; 31(3): 253-265, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36938666

RESUMO

Here we report a quantitative analysis of human metaphase II (MII) oocytes from a 22-year-old oocyte donor, retrieved after ovarian-controlled hyperstimulation. Five surplus donor oocytes were processed for transmission electron microscopy (TEM), and a stereological analysis was used to quantify the distribution of organelles, using the point-counting technique with an adequate stereological grid. Comparisons between means of the relative volumes (Vv) occupied by organelles in the three oocyte regions, cortex (C), subcortex (SC) and inner cytoplasm (IC), followed the Kruskal-Wallis test and Mann-Whitney U-test with Bonferroni correction. Life cell imaging and TEM analysis confirmed donor oocyte nuclear maturity. Results showed that the most abundant organelles were smooth endoplasmic reticulum (SER) elements (26.8%) and mitochondria (5.49%). Significant differences between oocyte regions were found for lysosomes (P = 0.003), cortical vesicles (P = 0.002) and large SER vesicles (P = 0.009). These results were quantitatively compared with previous results using prophase I (GV) and metaphase I (MI) immature oocytes. In donor MII oocytes there was a normal presence of cortical vesicles, SER tubules, SER small, medium and large vesicles, lysosomes and mitochondria. However, donor MII oocytes displayed signs of cytoplasmic immaturity, namely the presence of dictyosomes, present in GV oocytes and rare in MI oocytes, of SER very large vesicles, characteristic of GV oocytes, and the rarity of SER tubular aggregates. Results therefore indicate that the criterion of nuclear maturity used for donor oocyte selection does not always correspond to cytoplasmic maturity, which can partially explain implantation failures with the use of donor oocytes.


Assuntos
Mitocôndrias , Oócitos , Humanos , Adulto Jovem , Adulto , Oócitos/metabolismo , Citoplasma , Oogênese , Núcleo Celular
3.
Food Control ; 137: 108959, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35783559

RESUMO

Epidemiological studies show that improper food handling practices at home account for a significant portion of foodborne illness cases. Mishandling of raw meat during meal preparation is one of the most frequent hazardous behaviours reported in observational research studies that potentially contributes to illness occurrence, particularly through the transfer of microbial pathogens from the raw meat to ready-to-eat (RTE) foods. This study evaluated the transfer of two major foodborne pathogens, Salmonella enterica and Listeria monocytogenes, from artificially contaminated chicken meat to lettuce via cooking salt (used for seasoning) during simulated domestic handling practices. Pieces of chicken breast fillets were spiked with five different loads (from ca. 1 to 5 Log CFU/g) of a multi-strain cocktail of either S. enterica or L. monocytogenes. Hands of volunteers (gloved) contaminated by handling the chicken, stirred the cooking salt that was further used to season lettuce leaves. A total of 15 events of cross-contamination (three volunteers and five bacterial loads) were tested for each pathogen. Immediately after the events, S. enterica was isolated from all the cooking salt samples (n = 15) and from 12 samples of seasoned lettuce; whereas L. monocytogenes was isolated from 13 salt samples and from all the seasoned lettuce samples (n = 15). In addition, S. enterica and L. monocytogenes were able to survive in artificially contaminated salt (with a water activity of 0.49) for, at least, 146 days and 126 days, respectively. The ability of these foodborne pathogens to survive for a long time in cooking salt, make it a good vehicle for transmission and cross-contamination if consumers do not adopt good hygiene practices when preparing meals.

4.
Food Microbiol ; 87: 103351, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31948609

RESUMO

The objective of this work was to investigate the effect of stress conditions frequently encountered in food-associated environments on virulence-associated characteristics of eight strains of Listeria monocytogenes. Strains were grown at low (11 °C, cold stress) and optimal (37 °C) temperatures and in high NaCl concentrations (6% NaCl, 11 °C; cold-osmotic stress) and tested for their ability to invade the human intestinal epithelial Caco-2 cells. Results demonstrate that the correlation between exposure to cold stress and increased invasion phenotype is strain-dependent as strains investigated exhibited different behaviours, i.e. exposure to cold stress conditions resulted in a significant increase of invasion levels in five out of the eight strains tested, when compared to growth under optimal conditions. On the other hand, when these cold-adapted cells were subsequently submitted to high salt concentrations and low temperature, their enhanced ability to invade Caco-2 was lost. Surprisingly, saturated fatty acids (SFA) and branched chain fatty acids (BCFA) decreased when L. monocytogenes were exposed to stress conditions as opposed to what has been observed in other studies, therefore highlighting that further studies will need to deepen in the understanding of the lipid metabolism of these strains. The effect of stress conditions on the survival of three selected L. monocytogenes strains through an in vitro gastrointestinal (GI) tract digestion model was further investigated. The exposure to cold-osmotic stress increased the survival of one strain through the GI tract.


Assuntos
Listeria monocytogenes/fisiologia , Listeriose/microbiologia , Adaptação Fisiológica , Células CACO-2 , Temperatura Baixa , Contagem de Colônia Microbiana , Humanos , Listeria monocytogenes/química , Listeria monocytogenes/crescimento & desenvolvimento , Listeria monocytogenes/patogenicidade , Pressão Osmótica , Cloreto de Sódio/metabolismo , Estresse Fisiológico , Virulência
5.
Zygote ; 28(4): 308-317, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32285762

RESUMO

We have previously presented a stereological analysis of organelle distribution in human prophase I oocytes. In the present study, using a similar stereological approach, we quantified the distribution of organelles in human metaphase I (MI) oocytes also retrieved after ovarian stimulation. Five MI oocytes were processed for transmission electron microscopy and a classical manual stereological technique based on point-counting with an adequate stereological grid was used. Kruskal-Wallis and Mann-Whitney U-tests with Bonferroni correction were used to compare the means of relative volumes (Vv) occupied by organelles. In all oocyte regions, the most abundant organelles were mitochondria and smooth endoplasmic reticulum (SER) elements. No significant differences were observed in Vv of mitochondria, dictyosomes, lysosomes, or SER small and medium vesicles, tubular aggregates and tubules. Significant differences were observed in other organelle distributions: cortical vesicles presented a higher Vv (P = 0.004) in the cortex than in the subcortex (0.96% vs 0.1%) or inner cytoplasm (0.96% vs 0.1%), vesicles with dense granular contents had a higher Vv (P = 0.005) in the cortex than in the subcortex (0.1% vs 0%), and SER large vesicles exhibited a higher Vv (P = 0.011) in the inner cytoplasm than in the subcortex (0.2% vs 0%). Future stereological analysis of metaphase II oocytes and a combined quantitative data of mature and immature oocytes, will enable a better understanding of oocyte organelle distribution during in vivo maturation. Combined with molecular approaches, this may help improve stimulation protocols and in vitro maturation methods.


Assuntos
Técnicas Citológicas/métodos , Metáfase , Oócitos/citologia , Retículo Endoplasmático Liso , Feminino , Humanos , Microscopia Eletrônica de Transmissão , Mitocôndrias , Oócitos/ultraestrutura , Organelas , Indução da Ovulação , Fotografação
6.
Rev Port Cir Cardiotorac Vasc ; 27(2): 97-103, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32707616

RESUMO

Patients undergoing angioplasty and stent insertion require double prophylactic anti-aggregation or monotherapy. This is a challenging procedure with a high risk of morbidity and coronary mortality. The aim of this protocol is to provide guidelines for a presurgical approach to patients with a coronary stent who will be undergoing non-coronary surgery. This protocol highlights potential complications that may occur, namely those related with the cardiac stent and the evaluation of cardiac risk, and notes the thrombotic and hemorrhagic risks associated with the surgical procedure and the decision algorithms for both elective surgery and urgent surgery involving the suspension and re-introduction of antiplatelet therapy. Our main goal is to outline an optimized approach to these cases in order to improve cardiac outcomes and to minimize the risk of complications.


Assuntos
Oclusão Coronária , Stents , Oclusão Coronária/cirurgia , Procedimentos Cirúrgicos Eletivos , Humanos , Inibidores da Agregação Plaquetária , Fatores de Risco
7.
Dis Aquat Organ ; 135(3): 175-191, 2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31486410

RESUMO

We describe, morphologically and molecularly, a new actinosporean from the intestinal epithelium of the freshwater oligochaete Ilyodrilus templetoni in the upper estuary of the River Minho, Northern Portugal. Mature actinospores resembled both echinactinomyxon and raabeia types, emphasizing the previously known lack of a clear boundary between these 2 collective groups. Historically, raabeia and echinactinomyxon types have been differentiated solely based on the shape of the valvular processes being curved or straight, respectively. Our observations, however, show that this morphological character is too variable for distinguishing between these 2 collective groups, since the actinospores of the raabeia described here displayed valvular processes that could either be straight, downward or upward curved. Several similar cases can be found in the available literature. Considering this overlap in actinospore morphology, we propose that echinactinomyxon be deemed invalid and its types be included in raabeia, as the latter constitutes the older of the 2 groups. Known echinactinomyxon types, however, should not be renamed as raabeia, as this would create unnecessary confusion. Accordingly, a more comprehensive definition of the raabeia collective group is provided. Phylogenetic analyses revealed polyphyletic clustering of raabeia/echinactinomyxon types among members of the myxosporean suborders Variisporina and Platysporina, reiterating the lack of agreement between actinosporean morphotypes and myxosporean genera. The new type described here specifically clusters within the Paramyxidium clade, alongside other SSU rDNA sequences of raabeia, echinactinomyxon, aurantiactinomyxon and synactinomyxon. Considering that most Paramyxidium spp. parasitize Anguilla anguilla (Linnaeus, 1758), future myxozoan surveys in the River Minho should include this species.


Assuntos
Cnidários , Myxozoa , Oligoquetos , Animais , Água Doce , Filogenia
8.
Parasitol Res ; 118(12): 3279-3305, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31673834

RESUMO

Mullets are ecologic and commercially important fish species. Their ubiquitous nature allows them to play critical roles in freshwater and marine ecosystems but makes them more vulnerable to diseases and parasitic infection. In this study, a myxozoan survey was performed on three species of mullet captured from a northern Portuguese river. The results disclose a high biodiversity, specifically due to the hyperdiversification of Myxobolus. Thirteen new species of this genus are described based on microscopic and molecular procedures: 7 from the thinlip grey mullet Chelon ramada, 2 from the thicklip grey mullet Chelon labrosus, and 4 from the flathead grey mullet Mugil cephalus. Myxobolus exiguus and Ellipsomyxa mugilis are further registered from their type host C. ramada, as well as six more myxospore morphotypes that possibly represent distinct Myxobolus species. Overall, the results obtained clearly show that the number of host-, site- and tissue-specific Myxobolus spp. is much higher than what would be expected in accordance to available literature. This higher biodiversity is therefore discussed as either being the result of the usage of poor discriminative criteria in previous studies, or as being a direct consequence of the biological and ecological traits of the parasite and of its vertebrate and invertebrate host communities. Bayesian inference, maximum likelihood and maximum parsimony analyses position the new species within a clade comprising all other Myxobolus spp. that infect mugiliform hosts, thus suggesting that this parasitic group has a monophyletic origin. Clustering of species in relation to the host genus is also revealed and strengthens the contention that the evolutionary history of mugiliform-infecting Myxobolus reflects that of its vertebrate hosts. In this view, the hyperdiversification of Myxobolus in mullet hosts is hypothesized to correlate with the processes of speciation that led to the ecological plasticity of mullets.


Assuntos
Biodiversidade , Myxozoa/classificação , Smegmamorpha/parasitologia , Animais , Evolução Biológica , Especificidade de Hospedeiro , Myxobolus/classificação , Myxobolus/genética , Myxozoa/genética , Filogenia , Portugal , Rios/parasitologia , Smegmamorpha/classificação
10.
Syst Parasitol ; 94(1): 123-131, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-28062990

RESUMO

A new myxosporean parasite, Auerbachia maamouni n. sp., infecting the gallbladder of the golden trevally Gnathanodon speciosus Forsskål, is described, based on morphology, ultrastructure, and small subunit (SSU) rRNA gene sequencing. Of 50 fish collected from the Red Sea in Jeddah, Saudi Arabia, five were found heavily infected with mature myxospores floating free in the bile. Mature spores are pyriform to club-shaped with smooth valves, and contain a single polar capsule with an S-shaped polar filament, arranged in 13-16 polar filament coils, oriented longitudinally, with an irregular distribution on the polar capsule matrix. Spores measure 15.8 (14-17) µm in total length in lateral view, 7.9 (6-9) µm in width in apical view, with spore body length of 6.2 ± 0.4 (5-7) µm. The ellipsoidal polar capsule has two adjusted lateral folds 7.6 (6-8) µm long and 2 (2-3) µm wide. The new species is distinguished from other species of the genus based on spore morphometry and molecular data. The phylogenetic tree constructed using Maximum Likelihood and Bayesian Inference analysis of SSU rDNA sequence data supported the phylogenetic position of A. maamouni n. sp. among the species of Auerbachia Meglitsch, 1968 sequenced to date. Analysis of the SSU rDNA sequence data also supported the assumption that Auerbachia is closely related to members of the genera Coccomyxa Léger & Hesse, 1907, Zschokkella Auerbach, 1910 and Myxidium Bütschli, 1882, whose members inhabit the gallbladder of marine teleost fishes.


Assuntos
Vesícula Biliar/parasitologia , Myxozoa/classificação , Myxozoa/ultraestrutura , Filogenia , Animais , Oceano Índico , Myxozoa/genética , Perciformes/parasitologia , Especificidade da Espécie
11.
Zygote ; 23(6): 900-7, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25601002

RESUMO

Asthenozoospermia has been related to structural defects of the sperm flagellum. However, few reports have studied in detail the ultrastructure of sperm with total immotility. We present an ultrastructural study of sperm from five patients with total sperm immotility, four due to dysplasia of the fibrous sheath (DFS) and one with situs-inversus. Of the four patients with DFS, three cases presented a hypertrophic and hyperplastic fibrous sheath that invaded the midpiece space, absence of the annulus, and a short midpiece containing a few disorganized and pale mitochondria. Of these cases, two presented absence of the central complex and radial spokes; another additionally presented absence of dynein arms and nexin bridges; and the other patient presented an intact annulus with a dysplastic fibrous sheath restricted to the principal piece with disorganized microtubule doublets. The patient with situs-inversus presented severe respiratory symptoms, with absence of dynein arms and nexin bridges. In conclusion, we present three cases with DFS associated with total sperm immotility, abnormal mitochondria, and absence of the annulus, central pair complex and radial spokes, of which one had in addition absence of dynein arms and nexin bridges. We also describe a patient, with total sperm immotility and a different presentation of DFS, as the annulus was present and the dysplastic fibrous sheath was restricted to the principal piece. These findings thus confirm the heterogeneity of the DFS condition. The changes observed in the patient with situs-inversus also further support previous observations.


Assuntos
Infertilidade Masculina/patologia , Motilidade dos Espermatozoides , Espermatozoides/patologia , Espermatozoides/ultraestrutura , Adulto , Feminino , Humanos , Infertilidade Masculina/etiologia , Infertilidade Masculina/terapia , Masculino , Pessoa de Meia-Idade , Gravidez , Injeções de Esperma Intracitoplásmicas
12.
J Eukaryot Microbiol ; 61(6): 586-93, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25039988

RESUMO

Thelohanellus marginatus n. sp., a new myxosporean parasite infecting the primary gill filaments of the teleost fish Hypophthalmus marginatus (Pimelodidae) in the Amazon River, is described on the basis of microscopic and molecular procedures. The parasite forms whitish and ellipsoidal cysts up to 250 µm in diam. Myxospores ellipsoidal with a slightly more pointed anterior end, measuring 17.1 ± 0.6 µm in length, 6.9 ± 0.4 µm in width, and 5.1 ± 0.5 µm in thickness. A single pyriform polar capsule, 9.0 ± 0.3 µm long and 6.1 ± 0.4 µm wide, positioned slightly right to the medial plane in valvular view, contains a polar filament arranged in 4-5 coils. Molecular analysis of the SSU rRNA gene by Maximum Parsimony, Neighbor-Joining, and Maximum Likelihood revealed the parasite clustering among other myxobolids, namely Henneguya and Myxobolus. Host affinity is supported as an important evolutionary signal for the phylogeny of myxobolids. The parasite here described represents the first record of the genus Thelohanellus Kudo, 1933 from the South American fauna.


Assuntos
Doenças dos Peixes/parasitologia , Brânquias/parasitologia , Myxozoa/classificação , Myxozoa/citologia , Doenças Parasitárias em Animais/parasitologia , Animais , Especificidade de Hospedeiro , Microscopia Eletrônica de Transmissão , Myxozoa/genética , Myxozoa/ultraestrutura , Filogenia , Rios
13.
J Assist Reprod Genet ; 30(4): 487-95, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23359247

RESUMO

PURPOSE: Little is known about the apoptotic mechanisms involved in abnormal spermatogenesis. In order to describe the significance of apoptosis in azoospermia, testicular tissue from abnormal spermatogenesis was analysed. METHODS: Testicular treatment biopsies were obtained from 27 men. Five presented oligozoospermia, 9 obstructive azoospermia (4 congenital bilateral absence of the vas deferens; 5 secondary azoospermia) and 13 non-obstructive azoospermia (5 hypospermatogenis; 3 maturation arrest; 5 Sertoli-cell-only syndrome). Immunohistochemical staining was performed for active caspases-3, -8 and -9. The presence of active caspases in Sertoli cells and germ cells was analyzed using stereological tools. RESULTS: Increased active caspase-3 was found in Sertoli-cell-only syndrome. No significant differences were found in maturation arrest. In hypospermatogenesis, primary spermatocytes were the germ cells with higher active caspases. Oligozoospermia and secondary obstruction showed significant differences among germ cells for the presence of all active caspases. In oligozoospermia, spermatogonia presented significant increased active caspase-9 in relation to active caspase-8. In primary obstruction and hypospermatogenesis, germ cells presented significant increased active caspases-3 and -9. CONCLUSIONS: Results suggest that increased active caspase-3 might be involved in Sertoli-cell-only syndrome etiology. In cases of hypospermatogenesis, intrinsic lesions at the meiotic stage seem to be related to the pathology. In secondary obstruction apoptosis is suggested to be initiated due to extrinsic and intrinsic lesions, whereas in primary obstruction only the intrinsic apoptotic pathway seems to be present. Finally, in oligozoospermic patients spermatogonia death by mitochondrial damage additionally to meiosis malfunctioning, might be on the origin of the decreased sperm output.


Assuntos
Caspases/metabolismo , Transdução de Sinais , Espermatogênese/fisiologia , Espermatozoides/enzimologia , Azoospermia/enzimologia , Azoospermia/patologia , Caspase 3/metabolismo , Caspase 8/metabolismo , Caspase 9/metabolismo , Humanos , Masculino , Oligospermia/enzimologia , Síndrome de Células de Sertoli/enzimologia , Células de Sertoli/enzimologia , Espermatogônias/enzimologia , Espermatogônias/metabolismo , Espermatogônias/patologia
14.
J Morphol ; 284(3): e21562, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36719273

RESUMO

The gill of Aplysia depilans consists of several wedge-shaped pinnules with a highly folded structure, differing from the typical ctenidial gills of mollusks. Light microscopy and transmission electron microscopy were used to investigate this organ in juveniles and adults. In this species, the gill epithelium comprised ciliated, unciliated, and secretory cells. The ultrastructural analysis suggests other functions for the gill besides respiration. The deep cell membrane invaginations associated with mitochondria in the basal region of epithelium point to a role in ion regulation. Endocytosis and intracellular digestion were other activities detected in epithelial cells. In juveniles, an intranuclear crystalline structure was seen in some ciliated cells. The presence of an intranuclear crystalline structure was frequently associated with chromatin decondensation, swelling of the nuclear envelope and endoplasmic reticulum cisternae, and abundance of Golgi stacks. As these intranuclear inclusions were not found in the gill of the adult specimens, their occurrence in the two juveniles seems likely to be an anomalous condition whose cause cannot be established at the moment. Mucous cells were the most abundant secretory cells in the epithelium, but a few epithelial serous cells were also found. In addition, large protein-secreting subepithelial cells had the main cell body inserted in the connective tissue and a long thin neck crossing the epithelium. Mucous cells can be considered responsible for the production of the mucus layer that protects the epithelium, but the specific functions of the epithelial and subepithelial protein-secreting cells remain elusive. Below the epithelium, a layer of connective tissue with muscle cells lined the narrow hemolymph space. The connective tissue included cells with a large amount of rough endoplasmic reticulum cisternae. Bacteria were found on the surface of the gill, and the most abundant had a thin stalk for attachment to the epithelial cells.


Assuntos
Aplysia , Gastrópodes , Animais , Aplysia/ultraestrutura , Brânquias/ultraestrutura , Microscopia Eletrônica , Moluscos , Epitélio/ultraestrutura
15.
Parasite ; 30: 26, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37401858

RESUMO

A myxozoan survey was performed on specimens of thicklip grey mullet Chelon labrosus (Risso) captured from the Douro River estuary, northern Portugal. Eleven new species, all belonging to the genus Myxobolus Bütschli, 1882 (M. abdominalis n. sp., M. aestuarium n. sp., M. caudalis n. sp., M. chelonari n. sp., M. cucurbitiformis n. sp., M. douroensis n. sp., M. intestinicola n. sp., M. invictus n. sp., M. labicola n. sp., M. peritonaei n. sp., and M. pinnula n. sp.) are described based on microscopic and molecular data, confirming the known high radiation of these myxozoans in mullets. Additionally, Myxobolus pupkoi Gupta et al., 2022 is reported for the first time from C. labrosus, bringing forth a novel case of morphological plasticity between geographic isolates. We consider that molecular-based comparisons are imperative for the description of mugiliform-infecting Myxobolus, with distance estimation further matching two of the novel Myxobolus spp. with sphaeractinomyxon types previously reported from another Portuguese estuary. This finding supports sphaeractinomyxon as specific life cycle counterparts of Myxobolus that infect mullets. Phylogenetic analyses of 18S rDNA retrieved a monophyletic clade of mugiliform-infecting myxobolids comprising well-supported lineages of species parasitizing mullets from the genera Chelon, Mugil, Crenimugil, and Planiliza. The existence of more than one Chelon- and Planiliza-infecting lineage reveals that myxobolids parasitized members of these genera multiple times during their evolution. Lastly, the elevated number of unmatched sphaeractinomyxon sequences included in the Chelon-infecting lineages clearly shows that Myxobolus diversity hosted by this genus remains underrated.


Title: Un inventaire des myxozoaires du mulet lippu Chelon labrosus confirme le rayonnement réussi de Myxobolus chez les hôtes mugiliformes. Abstract: Un inventaire des myxozoaires a été réalisé sur des spécimens de mulets lippus Chelon labrosus (Risso) capturés dans l'estuaire du fleuve Douro, au nord du Portugal. Onze nouvelles espèces, toutes appartenant au genre Myxobolus Bütschli, 1882 (M. abdominalis n. sp., M. aestuarium n. sp., M. caudalis n. sp., M. chelonari n. sp., M. cucurbitiformis n. sp., M. douroensis n. sp., M. intestinicola n. sp., M. invictus n. sp., M. labicola n. sp., M. peritonaei n. sp. et M. pinnula n. sp.) sont décrites sur la base de données microscopiques et moléculaires, confirmant le rayonnement connu de ces myxozoaires chez les mulets. De plus, Myxobolus pupkoi Gupta et al., 2022 est signalé pour la première fois chez C. labrosus, démontrant un nouveau cas de plasticité morphologique entre des isolats géographiques. Nous considérons que les comparaisons moléculaires sont impératives pour la description des Myxobolus infectant les mugiliformes, l'estimation de la distance correspondant en outre à deux des nouveaux Myxobolus spp. avec des types de sphaeractinomyxons précédemment signalés dans un autre estuaire portugais. Cette découverte soutient les sphaeractinomyxons en tant que contreparties spécifiques du cycle de vie de Myxobolus qui infectent les mulets. Les analyses phylogénétiques de l'ADNr 18S ont montré un clade monophylétique de Myxobolidae infectant les mugiliformes, comprenant des lignées robustes d'espèces parasitant les mulets des genres Chelon, Mugil, Crenimugil et Planiliza. L'existence de plusieurs lignées infectant Chelon et Planiliza révèle que les Myxobolidae ont parasité des membres de ces genres plusieurs fois au cours de leur évolution. Enfin, le nombre élevé de séquences de sphaeractinomyxons non appariées incluses dans les lignées infectant Chelon montre clairement que la diversité de Myxobolus hébergée par ce genre reste sous-estimée.


Assuntos
Doenças dos Peixes , Myxobolus , Myxozoa , Doenças Parasitárias em Animais , Smegmamorpha , Animais , Myxobolus/genética , Filogenia , Rios , Brânquias
16.
J Histochem Cytochem ; 71(4): 169-197, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37026452

RESUMO

Coronavirus disease (COVID-19) is caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). SARS-CoV-2 RNA has been found in the human testis on occasion, but subgenomic SARS-CoV-2 and infectious SARS-CoV-2 virions have not been found. There is no direct evidence of SARS-CoV-2 infection of testicular cells. To better understand this, it is necessary to determine whether SARS-CoV-2 receptors and proteases are present in testicular cells. To overcome this limitation, we focused on elucidating with immunohistochemistry the spatial distribution of the SARS-CoV-2 receptors angiotensin-converting enzyme 2 (ACE2) and cluster of differentiation 147 (CD147), as well as their viral spike protein priming proteases, transmembrane protease serine 2 (TMPRSS2) and cathepsin L (CTSL), required for viral fusion with host cells. At the protein level, human testicular tissue expressed both receptors and proteases studied. Both ACE2 and TMPRSS2 were found in interstitial cells (endothelium, Leydig, and myoid peritubular cells) and in the seminiferous epithelium (Sertoli cells, spermatogonia, spermatocytes, and spermatids). The presence of CD147 was observed in all cell types except endothelium and peritubular cells, while CTSL was exclusively observed in Leydig, peritubular, and Sertoli cells. These findings show that the ACE2 receptor and its protease TMPRSS2 are coexpressed in all testicular cells, as well as the CD147 receptor and its protease CTSL in Leydig and Sertoli cells, indicating that testicular SARS-CoV-2 infection cannot be ruled out without further investigation.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Masculino , SARS-CoV-2/genética , SARS-CoV-2/metabolismo , COVID-19/metabolismo , Enzima de Conversão de Angiotensina 2/metabolismo , Peptídeo Hidrolases/metabolismo , Testículo , RNA Viral , Peptidil Dipeptidase A/genética , Peptidil Dipeptidase A/metabolismo
17.
Int J Pharm ; 631: 122497, 2023 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-36529360

RESUMO

The extract obtained from Mikania glomerata leaves rich in ent-kaurenoic acid (ERKA) shows cytotoxic activity in vitro, but its hydrophobic nature and thermosensitivity are issues to be solved prior to in vivo antitumor studies. The purpose of this study was to investigate the antitumor activity of inclusion complexes formed between ERKA and ß-cyclodextrin (ERKA:ß-CD) in rodents. ERKA:ß-CD complexes obtained by malaxation (MX) and co-evaporation (CE) methods were firstly characterized regarding their physical properties, encapsulation efficiency, and cytotoxicity againts L929 cells. The antitumor activity study was then performed in mice with sarcoma 180 treated with saline, 5-fluouracil (5FU) and ERKA:ß-CD at 30, 100 and 300 µg/kg. The weight, volume, percentage of inhibition growth, gross and pathological features and positivity for TUNEL, ki67, NFκB and NRF2 in the tumors were assessed. Serum lactate-dehydrogenase activity (LDH), white blood cells count (WBC) and both gross and pathological features of the liver, kidneys and spleen were also evaluated. The formation of the inclusion complexes was confirmed by thermal analysis and FTIR, and they were non-toxic for L929 cells. The MX provided a better complexation efficiency. ERKA:ß-CD300 promoted significant tumor growth inhibition, and attenuated the tumor mitotic activity and necrosis content, comparable to 5-fluorouracil. ERKA:ß-CD300 also increased TUNEL-detected cell death, reduced Ki67 and NF-kB immunoexpression, and partially inhibited the serum LDH activity. No side effect was observed in ERKA:ß-CD300-treated animals. The ERKA:ß-CD inclusion complexes at 300 µg/kg displays antitumour activity in mice with low systemic toxicity, likely due to inhibition on the NF-kB signaling pathway and LDH activity.


Assuntos
Mikania , Neoplasias , Sarcoma 180 , beta-Ciclodextrinas , Camundongos , Animais , Mikania/química , Sarcoma 180/tratamento farmacológico , NF-kappa B , Antígeno Ki-67 , beta-Ciclodextrinas/química , Desenvolvimento de Medicamentos
18.
Dig Dis Sci ; 57(12): 3106-15, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22878915

RESUMO

BACKGROUND: In diabetes mellitus (DM), hyperglycemia promotes changes in biochemical mechanisms that induce oxidative stress. Oxidative stress has been closely linked to adverse consequences that affect the function of the gastrointestinal tract caused by injuries to the enteric nervous system (ENS) that in turn cause neurodegeneration and enteric glial loss. Therapeutic approaches have shown that diet supplementation with antioxidants, such as quercetin, reduce oxidative stress. AIMS: This work sought to evaluate neurons and enteric glial cells in the myenteric and submucosal plexuses of the duodenum in diabetic rats supplemented with quercetin. METHODS: The duodenum of 24 rats, including a control group (C), control quercetin supplementation group (CQ), diabetic group (D), and diabetic quercetin supplementation group (DQ), were used to investigate whole mounts of muscular and submucosal layers subjected to immunohistochemistry to detect vasoactive intestinal peptide in the myenteric layer and double-staining for HuC-D/neuronal nitric oxide synthase (nNOS) and HuC-D/S100. RESULTS: A reduction of the general neuronal population (HuC/D) was found in the myenteric and submucosal plexuses (p < 0.001) in the D and DQ groups. The nitrergic subpopulation (nNOS) decreased only in the myenteric plexus (p < 0.001), and glial cells decreased in both plexuses (p < 0.001) in the D and DQ groups. In diabetic rats, quercetin supplementation reduced neuronal and glial loss. Diabetes promoted an increase in the cell body area of both the general and nitrergic populations. Quercetin supplementation only prevented neuronal hypertrophy in the general population. CONCLUSION: Supplementation with quercetin eased the damage caused by diabetes, promoting a neuroprotective effect and reducing enteric glial loss in the duodenum.


Assuntos
Diabetes Mellitus Experimental/complicações , Duodeno/inervação , Sistema Nervoso Entérico/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Quercetina/farmacologia , Animais , Feminino , Masculino , Plexo Mientérico/citologia , Plexo Mientérico/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Neurônios/fisiologia , Ratos , Ratos Wistar , Estreptozocina , Plexo Submucoso/citologia , Plexo Submucoso/efeitos dos fármacos
19.
Nutr Neurosci ; 15(6): 283-8, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22889609

RESUMO

The present work studied the effects of ascorbic acid supplementation (1 mg/ml in water daily) on submucosal vasoactive intestinal polypeptide-immunoreactive (VIP-IR) neurons in the jejunum of aging rats. Twenty-five male rats were divided into the following groups: Y90 (young, 90-day-old rats), A345 (aged, 345-day-old rats), A428 (aged, 428-day-old rats), AA345 (ascorbic acid-supplemented rats, 90-345-day old), and AA428 (ascorbic acid-supplemented rats, 90-428-day old). Whole mounts of the submucosal layer were subjected to immunohistochemistry for determination of VIP-IR. Morphometric analyses were carried out in 100 submucosal VIP-IR neuron cell bodies from each group. At 345 days, neurons from supplemented animals were larger than those of non-supplemented animals of the same age. These results indicate that ascorbic acid neutralized free radicals and played a neuroprotective role. At 428 days, no significant differences between cell body areas were seen with or without ascorbic acid supplementation, indicating that, from a certain age onward, the role of ascorbic acid as a VIP-IR antioxidant was reduced. This supposition is supported by the fact that both supplemented and non-supplemented animals had higher blood concentrations of ascorbic acid on Day 428 compared with Day 345. The possible neuroprotective and neurodegenerative effects of ascorbic acid appear to depend on the age of the animals, dose, and its interaction with other antioxidants.


Assuntos
Envelhecimento/efeitos dos fármacos , Ácido Ascórbico/farmacologia , Jejuno/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Peptídeo Intestinal Vasoativo/metabolismo , Animais , Antioxidantes/farmacologia , Ácido Ascórbico/sangue , Suplementos Nutricionais , Relação Dose-Resposta a Droga , Jejuno/citologia , Masculino , Neurônios/patologia , Neuroproteção , Ratos , Ratos Wistar
20.
Syst Parasitol ; 82(3): 241-7, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22711511

RESUMO

Myxobolus myleus n. sp. is described from the gall-bladder of the freshwater fish Myleus rubripinnis collected near the city of Oriximiná in the Amazon System, Brazil. The spores obtained from the bile contained two equal symmetrical and smooth valves, each forming the spore wall. The spores were large, with a cone-like form, a semi spherical basal contour and measured (in µm) 19.3 ± 0.5 (n = 25) × 8.3 ± 0.5 (n = 25) × 4.0 ± 0.3 (n = 15). The apical end of the spores contained two elongate, equal and pointed conical polar capsules measuring 13.2 ± 0.4 µm (n = 25) in length and 3.0 ± 0.3 µm (n = 15) in width, each having a slightly tapering polar filament with 19 to 21 turns. The polar capsules were extended below at about 4/5 of the total length of the spores. The sporoplasm was binucleate and contained some sporoplasmosomes. All infected fish presented hypertrophy of the gall-bladder due to presence of the brownish parasite floating in the bile. In this paper we describe this new species of myxosporean based on light and ultrastructural observations, together with its associated pathology.


Assuntos
Bile/parasitologia , Characidae/parasitologia , Doenças dos Peixes/patologia , Myxobolus/anatomia & histologia , Myxobolus/isolamento & purificação , Doenças Parasitárias em Animais/patologia , Animais , Brasil , Doenças dos Peixes/parasitologia , Água Doce , Microscopia , Myxobolus/patogenicidade , Doenças Parasitárias em Animais/parasitologia
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