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1.
J Anat ; 245(2): 303-323, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38581181

RESUMO

This study investigated the pancreas differentiation of two species of gekkotan families-the mourning gecko Lepidodactylus lugubris (Gekkonidae) and the leopard gecko Eublepharis macularius (Eublepharidae)-based on two-dimensional (2D) histological samples and three-dimensional (3D) reconstructions of the position of the pancreatic buds and the surrounding organs. The results showed that at the moment of egg laying, the pancreas of L. lugubris is composed of three distinct primordia: one dorsal and two ventral. The dorsal primordium differentiates earlier than either ventral primordium. The right ventral primordium is more prominent and distinctive, starting to form earlier than the left one. Moreover, at this time, the pancreas of the leopard gecko is composed of the dorsal and right ventral primordium and the duct of the left ventral primordium. It means that the leopard gecko's left primordium is a transitional structure. These results indicate that the early development of the gekkotan pancreas is species specific. The pancreatic buds of the leopard and mourning gecko initially enter the duodenum by separate outlets, similar to the pancreas of other vertebrates. The pancreatic buds (3 of the mourning gecko and 2 of the leopard gecko) fuse quickly and form an embryonic pancreas. After that, the structure of this organ changes. After fusion, the pancreas of both gekkotans comprises four parts: the head of the pancreas (central region) and three lobes: upper, splenic, and lower. This organ develops gradually and is very well distinguished at hatching time. In both gekkotan species, cystic, hepatic, and pancreatic ducts enter the duodenum within the papilla. During gekkotan pancreas differentiation, the connection between the common bile duct and the dorsal pancreatic duct is associated with intestinal rotation, similar to other vertebrates.


Assuntos
Lagartos , Pâncreas , Animais , Lagartos/embriologia , Lagartos/anatomia & histologia , Pâncreas/embriologia , Pâncreas/anatomia & histologia , Imageamento Tridimensional
2.
J Anat ; 243(4): 618-629, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37013262

RESUMO

Gekkotans are one of the major clades of squamate reptiles. As one of the earliest-diverging lineages, they are crucial in studying deep-level squamate phylogeny and evolution. Developmental studies can shed light on the origin of many important morphological characters, yet our knowledge of cranial development in gekkotans is very incomplete. Here, we describe the embryonic development of the skull in a parthenogenetic gekkonid, the mourning gecko (Lepidodactylus lugubris), studied using non-acidic double staining and histological sectioning. Our analysis indicates that the pterygoid is the first ossifying bone in the skull, as in almost all other studied squamates, followed closely by the surangular and prearticular. The next to appear are the dentary, frontal, parietal and squamosal. The tooth-bearing upper jaw bones, the premaxilla and maxilla, develop relatively late. In contrast to previous reports, the premaxilla starts ossifying from two distinct centres, reminiscent of the condition observed in diplodactylids and eublepharids. Only a single ossification centre of the postorbitofrontal is observed. Some of the endochondral bones of the braincase (prootic, opisthotic, supraoccipital) and the dermal parasphenoid are the last bones to appear. The skull roof is relatively poorly ossified near the time of hatching, with a large frontoparietal fontanelle still present. Many bones begin ossifying relatively later in L. lugubris than in the phyllodactylid Tarentola annularis, which suggests that its ossification sequence is heterochronic with respect to T. annularis.


Assuntos
Lagartos , Animais , Lagartos/anatomia & histologia , Crânio/anatomia & histologia , Cabeça , Desenvolvimento Embrionário , Pesar
3.
Sensors (Basel) ; 22(23)2022 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-36501987

RESUMO

The article presents an innovative vision monitoring method of overhead contact line (OCL) displacement, which utilizes a set of LED light points installed along it. A light point is an, LED fed from a battery. Displacements of the LED points, recorded by a camera, are interpreted as a change of OCL shape in time and space. The vision system comprises a camera, properly situated with respect to the OCL, which is capable of capturing a dozen light points in its field of view. The monitoring system can be scaled by increasing the number of LED points and video cameras; thus, this method can be used for monitoring the motion of other large-size objects (e.g., several hundred meters). The applied method has made it possible to obtain the following novel results: vibration damping in a contact wire is nonlinear by nature and its intensity depends on the wire vibration amplitude; the natural frequency of contact wire vibration varies, and it is a function of vibration amplitude; the natural frequency of contact wire vibration also depends on the wire temperature. The proposed method can be used to monitor the uplift of contact and messenger wires in laboratory conditions, or for experimental OCL testing, as well as for verifying simulation models of OCL.

4.
J Anat ; 238(2): 249-287, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33169847

RESUMO

The vomeronasal organ (VNO), nasal cavity, lacrimal duct, choanal groove, and associated parts of the superficial (soft tissue) palate are called the naso-palatal complex. Despite the morphological diversity of the squamate noses, little is known about the embryological basis of this variation. Moreover, developmental data might be especially interesting in light of the morpho-molecular discordance of squamate phylogeny, since a 'molecular scenario' implies an occurrence of unexpected scale of homoplasy also in olfactory systems. In this study, we used X-ray microtomography and light microscopy to describe morphogenesis of the naso-palatal complex in two gekkotans: Lepidodactylus lugubris (Gekkonidae) and Eublepharis macularius (Eublepharidae). Our embryological data confirmed recent findings about the nature of some developmental processes in squamates, for example, involvement of the lateral nasal prominence in the formation of the choanal groove. Moreover, our study revealed previously unknown differences between the studied gekkotans and allows us to propose redefinition of the anterior concha of Sphenodon. Interpretation of some described conditions might be problematic in the phylogenetic context, since they represent unknown: squamate, nonophidian squamate, or gekkotan features.


Assuntos
Lagartos/embriologia , Osso Nasal/embriologia , Palato/embriologia , Animais , Osso Nasal/diagnóstico por imagem , Palato/diagnóstico por imagem , Microtomografia por Raio-X
5.
Front Zool ; 17: 28, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32983242

RESUMO

BACKGROUND: Despite the diverse morphology of the adult squamate naso-palatal complex - consisting of the nasal cavity, vomeronasal organ (VNO), choanal groove, lacrimal duct and superficial palate - little is known about the embryology of these structures. Moreover, there are no comprehensive studies concerning development of the nasal cavity and VNO in relation to the superficial palate. In this investigation, we used X-ray microtomography and histological sections to describe embryonic development of the naso-palatal complex of iguanian lizard, the brown anole (Anolis sagrei). The purpose of the study was to describe the mechanism of formation of adult morphology in this species, which combines the peculiar anole features with typical iguanian conditions. Considering the uncertain phylogenetic position of the Iguania within Squamata, embryological data and future comparative studies may shed new light on the evolution of this large squamate clade. RESULTS: Development of the naso-palatal complex was divided into three phases: early, middle and late. In the early developmental phase, the vomeronasal pit originates from medial outpocketing of the nasal pit, when the facial prominences are weakly developed. In the middle developmental phase, the following events can be noted: the formation of the frontonasal mass, separation of the vestibulum, appearance of the lacrimal duct, and formation of the choanal groove, which leads to separation of the VNO from the nasal cavity. In late development, the nasal cavity and the VNO attain their adult morphology. The lacrimal duct establishes an extensive connection with the choanal groove, which eventually becomes largely separated from the oral cavity. CONCLUSIONS: Unlike in other tetrapods, the primordium of the lacrimal duct in the brown anole develops largely beyond the nasolacrimal groove. In contrast to previous studies on squamates, the maxillary prominence is found to participate in the initial fusion with the frontonasal mass. Moreover, formation of the choanal groove occurs due to the fusion of the vomerine cushion to the subconchal fold, rather than to the choanal fold. The loss or significant reduction of the lateral nasal concha is secondary. Some features of anole adult morphology, such as the closure of the choanal groove, may constitute adaptations to vomeronasal chemoreception.

6.
Front Zool ; 14: 1, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28101121

RESUMO

BACKGROUND: Snakes are considered to be vomerolfaction specialists. They are members of one of the most diverse groups of vertebrates, Squamata. The vomeronasal organ and the associated structures (such as the lacrimal duct, choanal groove, lamina transversalis anterior and cupola Jacobsoni) of adult lizards and snakes have received much anatomical, histological, physiological and behavioural attention. However, only limited embryological investigation into these structures, constrained to some anatomical or cellular studies and brief surveys, has been carried out thus far. The purpose of this study was, first, to examine the embryonic development of the vomeronasal organ and the associated structures in the grass snake (Natrix natrix), using three-dimensional reconstructions based on histological studies, and, second, to compare the obtained results with those presented in known publications on other snakes and lizards. RESULTS: Five major developmental processes were taken into consideration in this study: separation of the vomeronasal organ from the nasal cavity and its specialization, development of the mushroom body, formation of the lacrimal duct, development of the cupola Jacobsoni and its relation to the vomeronasal nerve, and specialization of the sensory epithelium. Our visualizations showed the VNO in relation to the nasal cavity, choanal groove, lacrimal duct and cupola Jacobsoni at different embryonic stages. We confirmed that the choanal groove disappears gradually, which indicates that this structure is absent in adult grass snakes. On our histological sections, we observed a gradual growth in the height of the columns of the vomeronasal sensory epithelium and widening of the spaces between them. CONCLUSIONS: The main ophidian taxa (Scolecophidia, Henophidia and Caenophidia), just like other squamate clades, seem to be evolutionarily conservative at some levels with respect to the VNO and associated structures morphology. Thus, it was possible to homologize certain embryonic levels of the anatomical and histological complexity, observed in the grass snake, with adult conditions of certain groups of Squamata. This may reflect evolutionary shift in Squamata from visually oriented predators to vomerolfaction specialists. Our descriptions offer material useful for future comparative studies of Squamata, both at their anatomical and histological levels.

7.
Opt Lett ; 41(11): 2592-5, 2016 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-27244422

RESUMO

In this Letter, we demonstrate a graphene mode-locked, all-fiber Ho-doped fiber laser generating 1.3 nJ energy pulses directly from the oscillator. The graphene used as a saturable absorber was obtained via chemical vapor deposition on copper substrate and immersed in a poly(methyl methacrylate) support. The laser generated ultrashort soliton pulses at 2080 nm with bandwidth up to 6.1 nm. The influence of the output coupling ratio and the SA modulation depth on the mode-locking performance was also investigated.

8.
Dermatol Online J ; 19(2): 3, 2013 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-23473273

RESUMO

Primary cutaneous plasmacytomas are rare and little is known about their treatment and progression. We describe for the first time the predilection of primary cutaneous plasmacytoma to occur in a scar or sites of trauma. We report an 89-year-old man who presented with a slowly expanding asymptomatic mass over his pacemaker implantation, 1 year after insertion. Further investigation ruled out multiple myeloma and histology confirmed it to be a cutaneous plasmacytoma. This was treated successfully by local radiotherapy after extraction of the pacemaker and implantation of a new pacemaker on the opposite side. The patient subsequently developed an additional cutaneous plasmacytoma over the new pacemaker site, followed by the development of progressive multiple myeloma. Primary cutaneous plasmacytoma can show predilection for sites of trauma or surgery. Surgical excision of the plasmocytoma and local radiotherapy may be a reasonable strategy in the first initially after pacemaker removal.


Assuntos
Cicatriz/complicações , Mieloma Múltiplo/etiologia , Marca-Passo Artificial/efeitos adversos , Plasmocitoma/etiologia , Neoplasias Cutâneas/etiologia , Idoso de 80 Anos ou mais , Progressão da Doença , Evolução Fatal , Humanos , Masculino , Mieloma Múltiplo/patologia , Plasmocitoma/patologia , Recidiva , Neoplasias Cutâneas/patologia
9.
Opt Express ; 19(20): 19104-13, 2011 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-21996851

RESUMO

In this paper we present our experimental studies on controlling the amplified spontaneous emission (ASE) from Yb(3+) ions in Er/Yb co-doped fiber amplifiers. We propose a new method of controlling the Yb-ASE by stimulating a laser emission at 1064 nm in the amplifier, by providing a positive 1 µm signal feedback loop. The results are discussed and compared to a conventional amplifier setup without 1 µm ASE control and to an amplifier with auxiliary 1064 nm seeding. We have shown, that applying a 1064 nm signal loop in an Er/Yb amplifier can increase the output power at 1550 nm and provide stable operation without parasitic lasing at 1 µm.


Assuntos
Amplificadores Eletrônicos , Tecnologia de Fibra Óptica/instrumentação , Lasers de Estado Sólido , Luz , Espalhamento de Radiação , Telecomunicações , Desenho Assistido por Computador , Desenho de Equipamento , Reprodutibilidade dos Testes
10.
J Morphol ; 282(3): 378-407, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33340145

RESUMO

The sensory olfactory epithelium and the vomeronasal sensory epithelium (VSE) are characterized by continuous turnover of the receptor cells during postnatal life and are capable of regeneration after injury. The VSE, like the entire vomeronasal organ, is generally well developed in squamates and is crucial for detection of pheromones and prey odors. Despite the numerous studies on embryonic development of the VSE in squamates, especially in snakes, an ultrastructural analysis, as far as we know, has never been performed. Therefore, we investigated the embryology of the VSE of the grass snake (Natrix natrix) using electron microscopy (SEM and TEM) and light microscopy. As was shown for adult snakes, the hypertrophied ophidian VSE may provide great resolution of changes in neuron morphology located at various epithelial levels. The results of this study suggest that different populations of stem/progenitor cells occur at the base of the ophidian VSE during embryonic development. One of them may be radial glia-like cells, described previously in mouse. The various structure and ultrastructure of neurons located at different parts of the VSE provide evidence for neuronal maturation and aging. Based on these results, a few nonmutually exclusive hypotheses explaining the formation of the peculiar columnar organization of the VSE in snakes were proposed.


Assuntos
Colubridae/anatomia & histologia , Epitélio/ultraestrutura , Órgão Vomeronasal/ultraestrutura , Animais , Diferenciação Celular , Colubridae/embriologia , Embrião não Mamífero/anatomia & histologia , Embrião não Mamífero/ultraestrutura
11.
Radiol Imaging Cancer ; 3(5): e210048, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34559006

RESUMO

Purpose To compare disease detection of myeloma using contemporary whole-body (WB) MRI and fluorine 18 (18F) fluorodeoxyglucose (FDG) PET/CT protocols and to correlate imaging with laboratory estimates of disease burden, including molecular characteristics. Materials and Methods In this observational, prospective study, participants were recruited from November 2015 to March 2018 who had a diagnosis of myeloma, who were planned to undergo chemotherapy and autologous stem cell transplantation, and who underwent baseline WB-MRI and FDG PET/CT (ClinicalTrials.gov identifier NCT02403102). Baseline clinical data, including genetics, were collected. Paired methods were used to compare burden and patterns of disease. Results Sixty participants (mean age, 60 years ± 9 [standard deviation]; 35 men) underwent baseline WB-MRI and FDG PET/CT. WB-MRI showed significantly higher detection for focal lesions at all anatomic sites (except ribs, scapulae, and clavicles) and for diffuse disease at all sites. Two participants presented with two or more focal lesions smaller than 5 mm only at WB-MRI but not FDG PET/CT. Participants with diffuse disease at MRI had higher plasma cell infiltration (percentage of nucleated cells: median, 60% [interquartile range {IQR}, 50%-61%] vs 15% [IQR, 4%-50%]; P = .03) and paraprotein levels (median, 32.0 g/L [IQR, 24.0-48.0 g/L] vs 20.0 g/L [IQR, 12.0-22.6 g/L]; P = .02) compared with those without diffuse disease. All genetically high-risk tumors showed diffuse infiltration at WB-MRI. Conclusion WB-MRI helped detect a higher number of myeloma lesions than FDG PET/CT, and diffuse disease detected at WB-MRI correlated with laboratory measures of disease burden and molecular markers of risk. Keywords: MR-Imaging, Skeletal-Appendicular, Skeletal-Axial, Bone Marrow, Hematologic Diseases, Oncology Clinical trial registration no. NCT02403102. Supplemental material is available for this article. © RSNA, 2021.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Mieloma Múltiplo , Fluordesoxiglucose F18 , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/diagnóstico por imagem , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Estudos Prospectivos , Transplante Autólogo
12.
Hematol J ; 5(1): 47-54, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-14745430

RESUMO

Abnormalities of TP53 in chronic lymphocytic leukaemia (CLL) correlate with aggressive disease and transformation. We studied 115 patients with CLL including 90 untreated, 25 with heavily pretreated/refractory CLL using fluorescent in situ hybridisation (FISH) to detect allelic loss at chromosome 17p and flow cytometry (FC) to test p53 protein overexpression. A total of 17 cases were identified with TP53 deletion and/or protein expression. Both tests correlated in 10 of 17 patients; in six, one or the other abnormality was detected and in one case, with a deletion, flow cytometry failed. Material for direct DNA sequencing was available in 14 of 17 cases. Mutations were found in seven cases. Five of 14 patients with allelic loss and seven of 13 expressing p53 protein had a mutation. These were single-base substitutions and were located in exons 5, 7 or 8. Mutations were not found in 13 of 14 other cases without deletions by FISH or protein expression. The incidence of p53 abnormalities in this series was 15%, with a significant difference between untreated patients (7%) and the pretreated/refractory group (50%; P<0.01). Abnormal p53 was predicted for shorter survival, regardless of the method used. We confirm that p53 abnormalities are more common in refractory CLL and that mutations occur at the known hot spots. Testing for TP53 deletions by FISH and protein expression by FC is an effective and simple way of screening patients who are likely to have aggressive disease. DNA sequencing adds little to these methods in identifying the population at risk.


Assuntos
Leucemia Linfocítica Crônica de Células B/diagnóstico , Leucemia Linfocítica Crônica de Células B/genética , Mutação , Proteína Supressora de Tumor p53/genética , Análise Mutacional de DNA/normas , Resistência a Medicamentos/genética , Humanos , Hibridização in Situ Fluorescente , Leucemia Linfocítica Crônica de Células B/patologia , Prognóstico , Modelos de Riscos Proporcionais , Análise de Sequência de DNA , Análise de Sobrevida , Proteína Supressora de Tumor p53/análise
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