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1.
J Helminthol ; 98: e35, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38651383

RESUMO

As part of a parasitological survey, several specimens of two new monopisthocotylean species, Neotetraonchus celsomanueli sp. nov. and N.peruvianus sp. nov. (Dactylogyridea, Dactylogyridae), were collected from the gill filaments of the Peruvian sea catfish Galeichthys peruvianus (Siluriformes, Ariidae) off Puerto Pizarro, Tumbes region, Peru. Neotetraonchus celsomanueli sp. nov. is characterised by an MCO with a T-shaped distal end and an accessory piece that is ribbed and expanded proximally with a worm-shaped termination. Neotetraonchus peruvianus sp. nov. is typified by its MCO, which has a sledgehammer-shaped distal end and an accessory piece with a claw-shaped distal end. Additionally, N.peruvianus sp. nov. is characterised by its jellyfish-shaped onchium. A partial 28S rDNA sequence was obtained from N.celsomanueli sp. nov., and a phylogenetic analysis was conducted. This analysis revealed the phylogenetic position of Neotetraonchus celsomanueli sp. nov. within a clade comprising monopisthocotylean parasites of diadromous and marine ariid catfishes, including Hamatopeduncularia spp., Chauhanellus spp., Thysanotohaptor Kritsky, Shameem, Kumari & Krishnaveni, , and Neocalceostomoides spinivaginalis Lim, 1995. This finding brings the number of known Neotetraonchus species to seven and represents the first described Neotetraonchus species infecting marine catfishes from Peru.


Assuntos
Peixes-Gato , Doenças dos Peixes , Brânquias , Filogenia , Animais , Peixes-Gato/parasitologia , Peru , Doenças dos Peixes/parasitologia , Brânquias/parasitologia , Infecções por Trematódeos/veterinária , Infecções por Trematódeos/parasitologia , DNA Ribossômico/genética , Trematódeos/classificação , Trematódeos/genética , Trematódeos/anatomia & histologia , Trematódeos/isolamento & purificação , DNA de Helmintos/genética , RNA Ribossômico 28S/genética , Platelmintos/classificação , Platelmintos/genética , Platelmintos/anatomia & histologia , Platelmintos/isolamento & purificação , Análise de Sequência de DNA
2.
Acta Parasitol ; 69(1): 898-909, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38472688

RESUMO

OBJECTIVES: The present work aims to expand the knowledge of the digenean species Prosogonotrema bilabiatum (Sclerodistomidae), a parasite of Chaetodipterus faber (Acanthuriformes) from Brazil, with an integrative taxonomic approach, using light microscopy, scanning electron microscopy, histology, and molecular biology. METHODS: Forty-one digenean specimens were stained with hydrochloric carmine for morphological studies. Eleven parasites were dehydrated through a graded ethanol series, critical point dried with carbon dioxide, and coated with gold for scanning electron microscopy analysis. Four specimens were processed following histological routine and stained with hematoxylin and eosin and Gomori trichrome. DNA extracted was amplified using 28S partial primer D1-D3. Maximum likelihood and Bayesian inference were performed for phylogenetic analysis. RESULTS: Morphometric and morphological data of the specimens studied ranged in accordance as observed in previous descriptions of the species. Observations from scanning electron microscopy and histology corroborated with those observed in stained whole mounts. Molecular analysis showed that specimens of P. bilabiatum from Brazil clustered with another two sequences of this species from different hosts and localities, with a high node support value. CONCLUSIONS: The integrative taxonomic approach allowed to record and describe new characteristics of P. bilabiatum related to the tegument, the structure and the arrangement of its tissues. The use of molecular markers confirmed that specimens identified as P. bilabiatum from different hosts and localities are all conspecific. Further studies, mainly molecular with less conserved genetic markers, should be carried out to better understand the phylogenetic relationships of Prosogonotrema with Hemiuroidea.


Assuntos
Doenças dos Peixes , Microscopia Eletrônica de Varredura , Filogenia , Trematódeos , Infecções por Trematódeos , Animais , Brasil/epidemiologia , Doenças dos Peixes/parasitologia , Trematódeos/classificação , Trematódeos/genética , Trematódeos/ultraestrutura , Trematódeos/anatomia & histologia , Trematódeos/isolamento & purificação , Microscopia Eletrônica de Varredura/veterinária , Infecções por Trematódeos/parasitologia , Infecções por Trematódeos/veterinária , Infecções por Trematódeos/epidemiologia , Peixes/parasitologia , DNA de Helmintos/genética , RNA Ribossômico 28S/genética
3.
Clin Oncol (R Coll Radiol) ; 36(1): 3-5, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38135360
4.
Clin Oncol (R Coll Radiol) ; 35(12): 761-763, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37977692
5.
Clin Oncol (R Coll Radiol) ; 35(10): 627-629, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37679018
6.
Clin Oncol (R Coll Radiol) ; 35(8): 556-558, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37394266
7.
Zygote ; 31(5): 507-516, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37492001

RESUMO

Wagyu bulls are known to have a highly exacerbated libido, as shown by the intense sexual interest of young calves. Therefore we believe that Wagyu male animals have specialized Sertoli and Leydig cells that are directly involved with the sexual precocity in this breed as mature bulls have a small scrotal circumference. This study aimed to evaluate whether there were differences in the hormone and sperm characteristics of Wagyu bulls compared with the same characteristics of subspecies Bos indicus and Bos taurus sires. Frozen-thawed semen from Wagyu, Nellore, and Angus sires were analyzed for sperm kinetics (computer-assisted sperm analysis), plasma membrane integrity, chromatin integrity, acrosome status, mitochondrial activity, lipid peroxidation and hormone [luteinizing hormone (LH) and testosterone] serum concentration. The results showed that Wagyu had lower total motility and an increased number of sperm with no motility when compared with Nellore and Angus bulls. Wagyu breed did not differ from those breeds when considering plasma and acrosome membranes integrity, mitochondrial potential, chromatin resistance, sperm lipid peroxidation or hormone (LH and testosterone) concentrations. We concluded that Wagyu sires had lower total motility when compared with Nellore and Angus bulls. Wagyu breed did not differ from these breeds when considering plasma and acrosome membranes integrity, mitochondrial potential, chromatin resistance, sperm lipid peroxidation, or hormone (LH and testosterone) concentrations.


Assuntos
Sêmen , Motilidade dos Espermatozoides , Masculino , Bovinos , Animais , Contagem de Espermatozoides/veterinária , Espermatozoides , Testosterona , Cromatina
8.
Clin Oncol (R Coll Radiol) ; 35(6): 351-353, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37150545
9.
Clin Oncol (R Coll Radiol) ; 35(4): 216-218, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36894204
10.
J Mol Graph Model ; 121: 108443, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36870228

RESUMO

The main protease of SARS-CoV-2 (called Mpro or 3CLpro) is essential for processing polyproteins encoded by viral RNA. Several Mpro mutations were found in SARS-CoV-2 variants, which are related to higher transmissibility, pathogenicity, and resistance to neutralization antibodies. Macromolecules adopt several favored conformations in solution depending on their structure and shape, determining their dynamics and function. In this study, we used a hybrid simulation method to generate intermediate structures along the six lowest frequency normal modes and sample the conformational space and characterize the structural dynamics and global motions of WT SARS-CoV-2 Mpro and 48 mutations, including mutations found in P.1, B.1.1.7, B.1.351, B.1.525 and B.1.429+B.1.427 variants. We tried to contribute to the elucidation of the effects of mutation in the structural dynamics of SARS-CoV-2 Mpro. A machine learning analysis was performed following the investigation regarding the influence of the K90R, P99L, P108S, and N151D mutations on the dimeric interface assembling of the SARS-CoV-2 Mpro. The parameters allowed the selection of potential structurally stable dimers, which demonstrated that some single surface aa substitutions not located at the dimeric interface (K90R, P99L, P108S, and N151D) are able to induce significant quaternary changes. Furthermore, our results demonstrated, by a Quantum Mechanics method, the influence of SARS-CoV-2 Mpro mutations on the catalytic mechanism, confirming that only one of the chains of the WT and mutant SARS-CoV-2 Mpros are prone to cleave substrates. Finally, it was also possible to identify the aa residue F140 as an important factor related to the increasing enzymatic reactivity of a significant number of SARS-CoV-2 Mpro conformations generated by the normal modes-based simulations.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , COVID-19/genética , Mutação , Peptídeo Hidrolases , Inibidores de Proteases/química , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Antivirais/química
11.
12.
13.
Clin Oncol (R Coll Radiol) ; 34(10): 617-619, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36115684
14.
J Helminthol ; 96: e34, 2022 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-35548870

RESUMO

The present paper describes a new species of Dermadena (Digenea) parasitizing Pseudobalistes naufragium in Puerto Pizarro, northern Peru, using light and scanning electronic microscopy (SEM). Additionally, molecular analysis was also performed to determine the phylogenetic affinities of Dermadena within the Lepocreadiidae. The new species is differentiated from Dermadena spatiosa, Dermadena stirlingi and Dermadena lactophrysi by presenting a curved and well-developed external seminal vesicle. Also, SEM revealed numerous dome-shaped tegument protuberances forming glandular papillae with transversal wrinkles arranged roughly in concentric rows around the acetabular region, varying in size from large at the middle of the body to small at the margin. In the molecular phylogeny, the new species formed a well-supported clade with sequences of species from the Lepocreadiidae, confirming that it belongs to this family.


Assuntos
Tetraodontiformes , Trematódeos , Infecções por Trematódeos , Animais , Oceano Pacífico , Filogenia , América do Sul , Trematódeos/genética , Infecções por Trematódeos/veterinária
15.
Clin Oncol (R Coll Radiol) ; 34(6): 351-352, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35512928
16.
Climacteric ; 25(5): 427-433, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35438053

RESUMO

Systemic lupus erythematosus (SLE) primarily affects women, who may need hormone therapy (HT) in menopause. There is, however, some concern as to its efficacy and safety. This systematic review aimed to determine the effect of HT on the activity of SLE and its safety. The study was a qualitative systematic review. Research was conducted with data retrieved from Embase, MEDLINE and Cochrane databases using MESH terms up to April 2021, with no bar on date or language. Sixteen studies were selected for analysis. Most of them showed HT to be effective in the treatment of menopausal symptoms with no impact in SLE activity, but one randomized clinical trial showed an increase in the number of thrombotic events. The present systematic review demonstrated the efficacy of HT for treating the menopausal symptoms of SLE patients. The risk of flare and thrombosis seems to be very low.


Assuntos
Lúpus Eritematoso Sistêmico , Menopausa , Terapia de Reposição de Estrogênios/efeitos adversos , Feminino , Hormônios/uso terapêutico , Humanos , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Ensaios Clínicos Controlados Aleatórios como Assunto
19.
Oper Dent ; 46(4): 428-437, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34624105

RESUMO

Little is known about the impact of bleaching on the optical properties of computer-aided design and computer-aided manufactured (CAD-CAM) monolithic materials. The aim of the present study was to evaluate the effect of one session of in-office bleaching on stain removal, staining susceptibility, translucency, and whiteness variations of CAD-CAM monolithic materials. Disks were fabricated from Lava Ultimate (LU), Vita Enamic (VE), Vita Suprinity (VS), and IPS e.max CAD (IPS). A spectrophotometer was used to register Commission Internationale de l'Eclairage L*a*b* coordinates. For stain removal, 80 specimens from each material were assessed at baseline (R0) and after immersion in deionized water or coffee for 36.5 days followed or not by bleaching with 40% hydrogen peroxide (R1). For staining susceptibility, 80 specimens from each material were analyzed at baseline (R0'), and after having been bleached or not and immersed in deionized water or coffee (R1'). Both analyses were calculated as the color difference (ΔE00) between R1-R0 and R1'-R0', respectively. Differences in translucency (ΔTP00) and whiteness (ΔWID) between R1-R0 and R1'-R0' were also calculated. Data were analyzed by three-way ANOVA and the Games-Howell post hoc test (α=0.05). Clinical significance was based on 50%:50% perceptibility and acceptability thresholds for ΔE00, ΔTP00 and ΔWID, respectively. Surfaces were analyzed by scanning electron microscopy. Coffee increased ΔE00 in LU, VE, and VS, and decreased their translucency and whiteness, whereas the IPS had only its whiteness affected. Bleaching after immersion in coffee decreased ΔE00 in LU and VE, and increased translucency and whiteness of LU, VE, and VS. No effect was observed on IPS. Bleaching before immersion in coffee decreased translucency of LU, but within the acceptable interval, while VE exhibited lower ΔE00, and became more translucent and less dark. Both VS and IPS were not affected. One session of in-office bleaching benefited optical properties of the previously stained LU, VE, and VS, without increasing their susceptibility to staining or adversely providing clinically unacceptable variations in their translucency and whiteness. All variations exhibited by the IPS were below the perceptible threshold.


Assuntos
Cerâmica , Resinas Compostas , Cor , Desenho Assistido por Computador , Porcelana Dentária , Teste de Materiais , Propriedades de Superfície
20.
Phys Imaging Radiat Oncol ; 19: 85-89, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34355071

RESUMO

BACKGROUND AND PURPOSE: Magnetic resonance (MR) guided radiotherapy utilizes MR images for (online) plan adaptation and image guidance. The aim of this study was to investigate the impact of variation in MR acquisition time and scan resolution on image quality, interobserver variation in contouring and interobserver variation in registration. MATERIALS AND METHODS: Nine patients with prostate cancer were included. Four T2-weighted 3D turbo spin echo (T2w 3D TSE) sequences were acquired with different acquisition times and resolutions. Two radiologists assessed image quality, conspicuity of the capsule, peripheral zone and central gland architecture and motion artefacts on a 5 point scale. Images were delineated by two radiation oncologists and interobserver variation was assessed by the 95% Hausdorff distance. Seven observers registered the MR images on the planning CT. Registrations were compared on systematic offset and interobserver variation. RESULTS: Acquisition times ranged between 1.3 and 6.3 min. Overall image quality and capsule definition were significantly worse for the MR sequence with an acquisition time of 1.3 min compared to the other sequences. Median 95% Hausdorff distance showed no significant differences in interobserver variation of contouring. Systematic offset and interobserver variation in registration were small (<1 mm) and of no clinical significance. CONCLUSIONS: Our results can be used to effectively shorten overall fraction time for online adaptive MR guided radiotherapy by optimising the imaging sequence used for registration. From the sequences studied, a sequence of 3.1 min with anisotropic voxels of 1.2 × 1.2 × 2.4 mm3 provided the shortest acquisition time without compromising image quality.

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