Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 1.416
Filtrar
1.
BMC Vet Res ; 20(1): 299, 2024 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-38971722

RESUMEN

BACKGROUND: Research on the effects of physical exercise on canine body composition is limited. The aim of this study was to investigate the effects of a physical exercise programme on bodyweight, body condition score (BCS) and chest, abdominal and thigh circumferences in dogs. Twenty-one healthy dogs of different breeds exercised together with their owners during an eight-week programme consisting of jogging and strength exercises. Standardised measurements were performed in triplicates with a measuring tape on standing dogs. Chest circumference was measured at three anatomical locations, abdomen at two and thigh at one. Data on bodyweight, BCS (9-point scale) and circumferences were analysed with mixed model repeated measures analyses to evaluate changes after the programme and effects of target distance. RESULTS: Seven dog owners choose a target distance of 2 km and 14 owners choose 5-10 km. Mean BCS decreased (P = 0.007) after the programme (5.1 ± 0.9 vs. 4.7 ± 0.6) but there was no effect of target distance. Almost all chest and abdominal circumference measurements decreased (P ≤ 0.007) with the 2 km group driving the reduction in chest circumference and the 5-10 km group driving the reduction in abdominal circumference. In contrast, thigh circumference (28.8 ± 0.4 vs. 30.2 ± 0.4) increased (P = 0.007) while bodyweight was maintained. There were positive correlations between BCS and abdominal/chest ratios before and after the programme (Pearson correlation; R square ≤ 0.43, P ≤ 0.0012) but the mean ratio remained constant. CONCLUSIONS: Results indicated a redistribution between total body fat and muscle mass in body composition of normal weight to slightly overweight dogs after the physical exercise programme. The use of bodyweight alone was not a reliable evaluation method to complement the BCS assessment. However, repeated measurements of chest, abdominal and thigh circumference might aid in the assessment of body composition in dogs performing physical exercise. Further research should include a control group and objective evaluations of total body fat and lean mass, in order to investigate the effectiveness of physical exercise as a freestanding method for decreasing BCS and increasing muscle mass in overweight dogs.


Asunto(s)
Composición Corporal , Peso Corporal , Condicionamiento Físico Animal , Tórax , Animales , Perros/fisiología , Masculino , Femenino , Tórax/anatomía & histología , Abdomen/anatomía & histología , Muslo/anatomía & histología
2.
Comput Biol Med ; 177: 108659, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38823366

RESUMEN

Automatic abdominal organ segmentation is an essential prerequisite for accurate volumetric analysis, disease diagnosis, and tracking by medical practitioners. However, the deformable shapes, variable locations, overlapping with nearby organs, and similar contrast make the segmentation challenging. Moreover, the requirement of a large manually labeled dataset makes it harder. Hence, a semi-supervised contrastive learning approach is utilized to perform the automatic abdominal organ segmentation. Existing 3D deep learning models based on contrastive learning are not able to capture the 3D context of medical volumetric data along three planes/views: axial, sagittal, and coronal views. In this work, a semi-supervised view-adaptive unified model (VAU-model) is proposed to make the 3D deep learning model as view-adaptive to learn 3D context along each view in a unified manner. This method utilizes the novel optimization function that assists the 3D model to learn the 3D context of volumetric medical data along each view in a single model. The effectiveness of the proposed approach is validated on the three types of datasets: BTCV, NIH, and MSD quantitatively and qualitatively. The results demonstrate that the VAU model achieves an average Dice score of 81.61% which is a 3.89% improvement compared to the previous best results for pancreas segmentation in multi-organ dataset BTCV. It also achieves an average Dice score of 77.76% and 76.76% for the pancreas under the single organ non-pathological NIH dataset, and pathological MSD dataset.


Asunto(s)
Imagenología Tridimensional , Humanos , Imagenología Tridimensional/métodos , Aprendizaje Profundo , Abdomen/diagnóstico por imagen , Abdomen/anatomía & histología , Tomografía Computarizada por Rayos X/métodos , Páncreas/diagnóstico por imagen , Páncreas/anatomía & histología , Bases de Datos Factuales
3.
Appl Ergon ; 119: 104311, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38763088

RESUMEN

To optimise soldier protection within body armour systems, knowledge of the boundaries of essential thoraco-abdominal organs is necessary to inform coverage requirements. However, existing methods of organ boundary identification are costly and time consuming, limiting widespread adoption for use on soldier populations. The aim of this study was to evaluate a novel method of using 3D organ models to identify essential organ boundaries from low dose planar X-rays and 3D external surface scans of the human torso. The results revealed that, while possible to reconstruct 3D organs using template 3D organ models placed over X-ray images, the boundary data (relating to the size and position of each organ) obtained from the reconstructed organs differed significantly from MRI organ data. The magnitude of difference varied between organs. The most accurate anatomical boundaries were the left, right, and inferior boundaries of the heart, and lateral boundaries for the liver and spleen. Visual inspection of the data demonstrated that 11 of 18 organ models were successfully integrated within the 3D space of the participant's surface scan. These results suggest that, if this method is further refined and evaluated, it has potential to be used as a tool for estimating body armour coverage requirements.


Asunto(s)
Abdomen , Antropometría , Imagenología Tridimensional , Hígado , Imagen por Resonancia Magnética , Humanos , Antropometría/métodos , Masculino , Hígado/diagnóstico por imagen , Hígado/anatomía & histología , Adulto , Abdomen/diagnóstico por imagen , Abdomen/anatomía & histología , Tórax/diagnóstico por imagen , Tórax/anatomía & histología , Bazo/diagnóstico por imagen , Bazo/anatomía & histología , Ropa de Protección , Torso/diagnóstico por imagen , Personal Militar , Corazón/diagnóstico por imagen , Corazón/anatomía & histología , Adulto Joven , Femenino
4.
J Imaging Inform Med ; 37(4): 1273-1281, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38383807

RESUMEN

Atlases of normal genomics, transcriptomics, proteomics, and metabolomics have been published in an attempt to understand the biological phenotype in health and disease and to set the basis of comprehensive comparative omics studies. No such atlas exists for radiomics data. The purpose of this study was to systematically create a radiomics dataset of normal abdominal and pelvic radiomics that can be used for model development and validation. Young adults without any previously known disease, aged > 17 and ≤ 36 years old, were retrospectively included. All patients had undergone CT scanning for emergency indications. In case abnormal findings were identified, the relevant anatomical structures were excluded. Deep learning was used to automatically segment the majority of visible anatomical structures with the TotalSegmentator model as applied in 3DSlicer. Radiomics features including first order, texture, wavelet, and Laplacian of Gaussian transformed features were extracted with PyRadiomics. A Github repository was created to host the resulting dataset. Radiomics data were extracted from a total of 531 patients with a mean age of 26.8 ± 5.19 years, including 250 female and 281 male patients. A maximum of 53 anatomical structures were segmented and used for subsequent radiomics data extraction. Radiomics features were derived from a total of 526 non-contrast and 400 contrast-enhanced (portal venous) series. The dataset is publicly available for model development and validation purposes.


Asunto(s)
Pelvis , Tomografía Computarizada por Rayos X , Humanos , Masculino , Femenino , Adulto , Tomografía Computarizada por Rayos X/métodos , Pelvis/diagnóstico por imagen , Pelvis/anatomía & histología , Estudios Retrospectivos , Adulto Joven , Abdomen/diagnóstico por imagen , Abdomen/anatomía & histología , Aprendizaje Profundo , Adolescente , Radiografía Abdominal , Atlas como Asunto , Radiómica
5.
J Imaging Inform Med ; 37(3): 1-16, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38347391

RESUMEN

Convolutional Neural Networks have been widely applied in medical image segmentation. However, the existence of local inductive bias in convolutional operations restricts the modeling of long-term dependencies. The introduction of Transformer enables the modeling of long-term dependencies and partially eliminates the local inductive bias in convolutional operations, thereby improving the accuracy of tasks such as segmentation and classification. Researchers have proposed various hybrid structures combining Transformer and Convolutional Neural Networks. One strategy is to stack Transformer blocks and convolutional blocks to concentrate on eliminating the accumulated local bias of convolutional operations. Another strategy is to nest convolutional blocks and Transformer blocks to eliminate bias within each nested block. However, due to the granularity of bias elimination operations, these two strategies cannot fully exploit the potential of Transformer. In this paper, a parallel hybrid model is proposed for segmentation, which includes a Transformer branch and a Convolutional Neural Network branch in encoder. After parallel feature extraction, inter-layer information fusion and exchange of complementary information are performed between the two branches, simultaneously extracting local and global features while eliminating the local bias generated by convolutional operations within the current layer. A pure convolutional operation is used in decoder to obtain final segmentation results. To validate the impact of the granularity of bias elimination operations on the effectiveness of local bias elimination, the experiments in this paper were conducted on Flare21 dataset and Amos22 dataset. The average Dice coefficient reached 92.65% on Flare21 dataset, and 91.61% on Amos22 dataset, surpassing comparative methods. The experimental results demonstrate that smaller granularity of bias elimination operations leads to better performance.


Asunto(s)
Redes Neurales de la Computación , Humanos , Abdomen/diagnóstico por imagen , Abdomen/anatomía & histología , Procesamiento de Imagen Asistido por Computador/métodos , Algoritmos , Tomografía Computarizada por Rayos X , Bases de Datos Factuales
6.
J Anat ; 245(1): 84-96, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38419134

RESUMEN

The vertebral column, a defining trait of all vertebrates, is organized as a concatenated chain of vertebrae, and therefore its support to the body depends on individual vertebral morphology. Consequently, studying the morphology of the vertebral centrum is of anatomical and clinical importance. Grass carp (GC) is a member of the infraclass Teleostei (teleost fish), which accounts for the majority of all vertebrate species; thus, its vertebral anatomical structure can help us understand vertebrate development and vertebral morphology. In this study, we have investigated the morphology and symmetry of the grass carp vertebral centrum using high-resolution micro-CT scans. To this end, three abdominal vertebrae (V9, V10, & V11) from eight grass carp were micro-CT scanned and then segmented using Dragonfly (ORS Inc.). Grass carp vertebral centrum conformed to the basic teleost pattern and demonstrated an amphicoelous shape (biconcave hourglass). The centrum's cranial endplate was smaller, less circular, and shallower compared to the caudal endplate. While the vertebral centrum demonstrated bilateral symmetry along the sagittal plane (left/right), the centrum focus was shifted dorsally and cranially, breaking dorsoventral and craniocaudal symmetry. The sum of these findings implies that the caudal aspect of grass carp vertebral centrum is bigger and more robust. Currently, we have no information whether this is due to nature, for example, differences in gene expression, or nurture, for example, environmental effect. As the vertebral parapophyses and spinous processes are slanted caudally, the direction of muscle action during swimming may create a gradient of stresses from cranial to caudal, resulting in a more robust caudal aspect of the vertebral centrum. Expanding our study to include additional quadrupedal and bipedal (i.e., human) vertebrae, as well as testing if these morphological aspects of the vertebrae are indeed plastic and can be affected by environmental factors (i.e., temperature or other stressors) may help answer this question.


Asunto(s)
Carpas , Microtomografía por Rayos X , Animales , Carpas/anatomía & histología , Microtomografía por Rayos X/métodos , Cuerpo Vertebral/diagnóstico por imagen , Cuerpo Vertebral/anatomía & histología , Abdomen/anatomía & histología , Abdomen/diagnóstico por imagen
7.
Vet Rec ; 194(2): e3668, 2024 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-38012021

RESUMEN

BACKGROUND: This study aimed to determine the ultrasonographic features and reference values of the abdominal anatomy in guinea pigs. METHODS: A complete abdominal ultrasonographic examination was performed in 20 adults and 20 young guinea pigs. The thickness of the wall of the gallbladder, stomach, duodenum, caecum, colon and urinary bladder (UB) was measured. Also, the adrenal glands (AGs) (width of the cranial and caudal poles, length), kidneys (length, width, height), ovaries (length, width), testes (length, width), uterus (width) and seminal glands (width) and the thickness of the spleen and pancreas were measured. All the measurements were compared between age groups and sexes. RESULTS: The liver, gallbladder, gastrointestinal tract, pancreas, spleen, kidneys, UB, AGs and great vessels were clearly visualised in all the guinea pigs. No significant statistical differences were found between the sexes, but there were statistically significant differences in the size of the kidneys, AGs, pancreas, spleen and reproductive organs between age groups. No significant differences in the wall thickness of the digestive system, gallbladder and UB were observed between groups. LIMITATIONS: The main limitation of this study is the lack of gross anatomical or histological correlation. CONCLUSIONS: The results of this study support the use of ultrasonography as a diagnostic tool in guinea pigs and provide reference values for the abdominal organs of this species.


Asunto(s)
Abdomen , Bazo , Femenino , Animales , Cobayas , Valores de Referencia , Abdomen/anatomía & histología , Abdomen/diagnóstico por imagen , Ultrasonografía/veterinaria , Bazo/diagnóstico por imagen , Bazo/anatomía & histología , Hígado
8.
Sci Data ; 10(1): 3, 2023 01 12.
Artículo en Inglés | MEDLINE | ID: mdl-36635312

RESUMEN

Laparoscopy is an imaging technique that enables minimally-invasive procedures in various medical disciplines including abdominal surgery, gynaecology and urology. To date, publicly available laparoscopic image datasets are mostly limited to general classifications of data, semantic segmentations of surgical instruments and low-volume weak annotations of specific abdominal organs. The Dresden Surgical Anatomy Dataset provides semantic segmentations of eight abdominal organs (colon, liver, pancreas, small intestine, spleen, stomach, ureter, vesicular glands), the abdominal wall and two vessel structures (inferior mesenteric artery, intestinal veins) in laparoscopic view. In total, this dataset comprises 13195 laparoscopic images. For each anatomical structure, we provide over a thousand images with pixel-wise segmentations. Annotations comprise semantic segmentations of single organs and one multi-organ-segmentation dataset including segments for all eleven anatomical structures. Moreover, we provide weak annotations of organ presence for every single image. This dataset markedly expands the horizon for surgical data science applications of computer vision in laparoscopic surgery and could thereby contribute to a reduction of risks and faster translation of Artificial Intelligence into surgical practice.


Asunto(s)
Abdomen , Inteligencia Artificial , Abdomen/anatomía & histología , Abdomen/cirugía , Algoritmos , Ciencia de los Datos , Tomografía Computarizada por Rayos X/métodos , Alemania
9.
J Morphol ; 283(6): 693-770, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35373404

RESUMEN

Recent studies of insect anatomy evince a trend towards a comprehensive and integrative investigation of individual traits and their evolutionary relationships. The abdomen of ants, however, remains critically understudied. To address this shortcoming, we describe the abdominal anatomy of Amblyopone australis Erichson, using a multimodal approach combining manual dissection, histology, and microcomputed tomography. We focus on skeletomusculature, but additionally describe the metapleural and metasomal exocrine glands, and the morphology of the circulatory, digestive, reproductive, and nervous systems. We describe the muscles of the dorsal vessel and the ducts of the venom and Dufour's gland, and characterize the visceral anal musculature. Through comparison with other major ant lineages, apoid wasps, and other hymenopteran outgroups, we provide a first approximation of the complete abdominal skeletomuscular groundplan in Formicidae, with a nomenclatural schema generally applicable to the hexapod abdomen. All skeletal muscles were identifiable with their homologs, while we observe potential apomorphies in the pregenital skeleton and the sting musculature. Specifically, we propose the eighth coxocoxal muscle as an ant synapomorphy; we consider possible transformation series contributing to the distribution of states of the sternal apodemes in ants, Hymenoptera, and Hexapoda; and we address the possibly synapomorphic loss of the seventh sternal-eighth gonapophyseal muscles in the vespiform Aculeata. We homologize the ovipositor muscles across Hymenoptera, and summarize demonstrated and hypothetical muscle functions across the abdomen. We also give a new interpretation of the proximal processes of gonapophyses VIII and the ventromedial processes of gonocoxites IX, and make nomenclatural suggestions in the context of evolutionary anatomy and ontology. Finally, we discuss the utility of techniques applied and emphasize the value of primary anatomical research.


Asunto(s)
Hormigas , Abdomen/anatomía & histología , Abdomen/diagnóstico por imagen , Animales , Hormigas/anatomía & histología , Evolución Biológica , Glándulas Exocrinas/anatomía & histología , Glándulas Exocrinas/diagnóstico por imagen , Músculos/anatomía & histología , Músculos/diagnóstico por imagen , Microtomografía por Rayos X
10.
PLoS Negl Trop Dis ; 15(12): e0009733, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34932549

RESUMEN

The males of many species of New World Phlebotomines produce volatile terpenoid chemicals, shown in Lutzomyia longipalpis s.l. to be sex/aggregation pheromones. Pheromone is produced by secretory cells which surround a cuticular reservoir which collects the pheromone and passes it through a cuticular duct to the surface of the insect. The pheromone then passes through specialised cuticular structures on the abdominal surface prior to evaporation. The shape and distribution of the specialised structures are highly diverse and differ according to species. In this study we used SEM to examine the interior cuticular pheromone collection and transport structures of 3 members of the Lu. longipalpis s.l. species complex and Migonemyia migonei. We found a new structure which we have called the manifold which appears to be a substantial extension of the interior tergal cuticle connected in-line with the cuticular duct and reservoir. The manifold of the Campo Grande member of the complex is longer and wider than the Jacobina member whereas the manifold of the Sobral member was shorter than both other members of the complex. Overall, the secretory apparatus of the Sobral member was smaller than the other two. The manifold of M. migonei was very different to those found in Lu. longipalpis s.l. and was positioned in a pit-like structure within the tergal cuticle. The secretory reservoir was connected by a short duct to the manifold. Differences in the size and shape of the manifold may be related to the chemical structure of the pheromone and may have taxonomic value. Examination of the interior cuticle by SEM may help to locate the secretory apparatus of vector species where pheromonal activity has been inferred from behavioural studies but the external secretory structures or pheromones have not yet been found.


Asunto(s)
Psychodidae/anatomía & histología , Psychodidae/metabolismo , Atractivos Sexuales/metabolismo , Abdomen/anatomía & histología , Animales , Femenino , Masculino
11.
PLoS One ; 16(12): e0261171, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34905569

RESUMEN

The use of "belly scoring" can offer a novel, non-invasive objective management tool to gauge food intake between individuals, groups, and populations, and thus, population fitness. As food availability is increasingly affected by predation, ecological competition, climate change, habitat modification, and other human activities, an accurate belly scoring tool can facilitate comparisons among wildlife populations, serving as an early warning indicator of threats to wildlife population health and potential population collapse. In social species, belly scores can also be a tool to understand social behavior and ranking. We developed and applied the first rigorous quantitative photogrammetric methodology to measure belly scores of wild painted dogs (Lycaon pictus). Our methodology involves: (1) Rigorous selection of photographs of the dorso/lateral profile of individuals at a right angle to the camera, (2) photogrammetrically measuring belly chord length and "belly drop" in pixels, (3) adjusting belly chord length as a departure from a standardized leg angle, and (4) converting pixel measurements to ratios to eliminate the need to introduce distance from the camera. To highlight a practical application, this belly score method was applied to 631 suitable photographs of 15 painted dog packs that included 186 individuals, all collected between 2004-2015 from allopatric painted dog populations in and around Hwange (n = 462) and Mana Pools National Parks (n = 169) in Zimbabwe. Variation in mean belly scores exhibited a cyclical pattern throughout the year, corresponding to biologically significant patterns to include denning demand and prey availability. Our results show significant differences between belly scores of the two different populations we assessed, thus highlighting food stress in the Hwange population. In the face of growing direct and indirect anthropogenic disturbances, this standardised methodology can provide a rapid, species-specific non-invasive management tool that can be applied across studies to rapidly detect emergent threats.


Asunto(s)
Abdomen/anatomía & histología , Procesamiento de Imagen Asistido por Computador/métodos , Fotogrametría/métodos , Abdomen/diagnóstico por imagen , Animales , Animales Salvajes , Perros , Femenino , Masculino
12.
Cladistics ; 37(6): 677-716, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34841585

RESUMEN

The systematics of Megalopodidae is not adequately known, in spite of it being a relatively small group of phytophagous beetles. The first phylogenetic analysis of Megalopodidae with a comprehensive generic representation (25 genera of 30 described, 10 subgenera and 77 species) is undertaken. A parsimony analysis under equal and implied weights was carried out based on 147 adult and larval morphological characters. Subfamilies Palophaginae and Zeugophorinae were recovered as monophyletic, by contrast with Megalopodinae, which proved to be paraphyletic. Atelederinae are proposed as a new subfamily. Also, three tribes and three subtribes within Megalopodinae are proposed: Leucasteini trib.n., Sphondyliini trib.n. and Megalopodini, the latter including Macrolophina subtrib.n., Temnaspidina subtrib.n. and Megalopodina. The genera Macrolopha, Kuilua, Poecilomorpha, Temnaspis, Antonaria, Agathomerus, Megalopus and Bothromegalopus were recovered as non-monophyletic. New delimitations of the polyphyletic genera Poecilomorpha and Macrolopha are proposed, Clythraxeloma is resurrected, and the subgenera of Agathomerus are suppressed. The following new combinations are proposed: Kuilua apicata (Fairmaire), K. nyassae (Jacoby), Poecilomorpha cribricollis (Pic), P. minuta (Pic), Clythraxeloma assamensis (Jacoby), C. bipartita (Lacordaeri), C. discolineata (Pic), C. downesii (Baly), C. gerstaeckeri (Westwood), C. laosensis (Pic), C. maculata (Pic), C. mouhoti (Baly), C. nigrocyanea (Motschulsky), C. pretiosa (Reineck), Temnaspis tricoloripes (Pic) and Barticaria faciatus (Dalman). Clythraxeloma cyanipennis Kraatz is a restored combination. Distribution patterns of Megalopodidae largely conform to the breakup of Gondwanaland, with its main clades having particular distributions: Andean-Australian (Palophaginae), Ethiopian (Leucasteini, Sphondyliini, and Macrolophina), Neotropical (Ateledrinae and Megalopodina) and Ethiopian-Oriental-Palaearctic (Temnaspidina the result of a secondary expansion. Zeugophorinae present a worldwide distribution, except for the Neotropical and Andean regions, which may be the result of geodispersal. The findings of the present study also shed light on groups with taxonomic issues, where phylogenetic analyses are strongly needed.


Asunto(s)
Escarabajos , Abdomen/anatomía & histología , Animales , Escarabajos/anatomía & histología , Escarabajos/clasificación , Escarabajos/genética , Femenino , Genitales Femeninos/anatomía & histología , Genitales Masculinos/anatomía & histología , Cabeza/anatomía & histología , Masculino , Filogenia , Tórax/anatomía & histología , Alas de Animales/anatomía & histología
14.
J Comput Assist Tomogr ; 45(3): 458-462, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34297515

RESUMEN

OBJECTIVE: This study aimed to assess the effects of abdominal fat content and anatomical changes on the measurement of bone mineral density using dual-energy X-ray absorptiometry (DXA). MATERIALS AND METHODS: The bone mineral density measurements were performed with quantitative computed tomography for patients who underwent DXA and abdominal CT on the same day. The effects of abdominal fat content and anatomic changes on the results of DXA were assessed. RESULTS: Of the 43 patients, 88.3% were women, 11.7% were men, and the mean age was 55.6 years (range, 32-72). There was a significant relationship between the error in the measurement of T-scores with DXA and osteophytic new bone formation (P = 0.011). There were significant relationships between the error in detecting osteoporosis with DXA and osteophytic new bone formation, facet joint degeneration, and aortic calcification (P < 0.05). CONCLUSIONS: Abdominal fat content does not significantly affect T-scores. However, DXA can give false-negative results in detecting osteoporosis, especially in patients with osteophyte new bone formation, facet joint degeneration, and aortic calcifications, all conditions primarily in elderly patients. In these cases, it is more appropriate to use quantitative computed tomography instead of DXA.


Asunto(s)
Abdomen/diagnóstico por imagen , Grasa Abdominal/diagnóstico por imagen , Absorciometría de Fotón/métodos , Osteoporosis/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Abdomen/anatomía & histología , Grasa Abdominal/anatomía & histología , Adulto , Anciano , Densidad Ósea , Femenino , Humanos , Masculino , Persona de Mediana Edad , Osteoporosis/patología , Sensibilidad y Especificidad
15.
ACS Appl Mater Interfaces ; 13(21): 24524-24531, 2021 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-34009931

RESUMEN

Abdominal sections of honeybees undergo numerous reciprocating motions during their lifetime. However, the overlapped contact areas adjacent to the abdominal sections have a shallow wear extent, a physical mechanism that remains obscure to date. Therefore, this study explored a biofrictional reduction model based on a solid surface texture and the hairy surface of the honeybee abdomen. We collected honeybee samples and observed their abdomens using a camera (Zeiss Stemi 508). Subsequently, we sliced these samples using a microtome and detected their microscopic friction. The exterior surface of the honeybee abdomen was not smooth but was distributed with a dense microvilli structure, which played a vital role in adjusting the friction reduction characteristics between the abdominal sections. When the adjacent abdominal sections moved relatively to each other, their upper and lower surfaces were not in direct rigid contact. Briefly, this study shows that the microscale hair arrays on the surface of the posterior abdominal segment can significantly reduce real contact area and friction, which considerably decreases wear or abrasion. The friction reduction mechanism alleviates the abrasion during the relative bending movement and saves a large amount of energy, which is essential for the honeybees' daily activities. This microtexture compliance friction reduction characteristic could be used to fabricate hierarchical surfaces for long-lasting friction reduction mechanisms, which increase the life of soft devices, including soft actuators and hinges.


Asunto(s)
Abdomen/fisiología , Abejas/fisiología , Abdomen/anatomía & histología , Animales , Abejas/anatomía & histología , Fricción
16.
Rev. bras. ciênc. vet ; 28(2): 86-91, abr./jun. 2021. il.
Artículo en Portugués | LILACS, VETINDEX | ID: biblio-1367378

RESUMEN

O conhecimento da localização dos órgãos nas diferentes regiões do corpo do animal é essencial para a prática clínica, cirúrgica e para o diagnóstico por imagem. O objetivo do estudo foi descrever a anatomia topográfica abdominal do Didelphisalbiventris. Foram utilizados quatro cadáveres (animais jovens), dois destes destinados para o estudo macroscópico em peças a fresco e os outros fixados em solução aquosa de formaldeído a 10%. Os cadáveres foram dissecados e as estruturas anatômicas identificadas, analisadas e fotografadas. A maioria dos órgãos localizados na região abdominal dos cadáveres da espécie D. albiventris apresentou posição similar aos dos caninos, porém, alguns órgãos e a localização de determinadas estruturas apresentaram particularidades importantes, como a presença dos ossos epipúbicos, a ausência do lobo hepático quadrado, a presença de um ceco desenvolvido e o cólon dividido em três segmentos.


The knowledge about localization of organs in different regions of the animal's body is essential for clinical, surgical and diagnostic imaging practice. The purpose of this study was to describe the abdominal topographic anatomy of Didelphis albiventris. Was used four dead bodys (young animals), two of these was intended for the macroscopic study of fresh pieces and the others fixed in 10% aqueous formaldehyde solution. The corpses was dissected and the anatomic structures was identified, analyzed and photographed. Most of the organs located in the abdominal region of cadavers from species D. albiventris presented structure and position similar to canines, however some of these organs and localization of structures presented important particularities, like the presence of epipubic bones, absence of square hepatic lobe, presence of an developed cecum and colon divided into three segments.


Asunto(s)
Animales , Zarigüeyas/anatomía & histología , Anatomía Veterinaria , Músculos Abdominales/anatomía & histología , Abdomen/anatomía & histología
17.
J Anat ; 238(6): 1472-1491, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33417250

RESUMEN

The meaning of the term 'abdomen' has become increasingly ambiguous, as it has to satisfy the contemporary requirements of natural language discourse, literature, gross and radiological anatomy and its role in ontologies supporting electronic records and data modelling. It is critical that there is an agreed understanding of the semantics of the abdominopelvic cavity, its component volumes including the abdomen proper, true and false pelvic cavities, and its boundaries and regional contents. The expression of part-whole (meronymic) relationships is essential for inferences to be drawn by computer algorithms, but unless these are rigorously reviewed and tested incorrect assumptions are drawn. The SNOMED CT terminology descriptions and hierarchy of anatomical concepts relating to the trunk were scrutinised for ambiguity and sub-optimal relationships using a panel of reference sources. Any identified errors were corrected and the impact of any changes reviewed iteratively by evaluating their effect on dependant hierarchies (modelled with the associated anatomical concepts). Anatomical concepts are generally structured according to a traditional gross standpoint, but in clinical practice covert complex regional notions are frequently used and during the evaluation process a new viewpoint relating to projectional (transmissive) or emissive radiological perspective was identified. The subtle but important differences in the boundaries, volumes and contents of these distinctive perspectives of the 'abdomen' are presented. Three significant complex variants have been identified which relate to the most common uses of the word 'abdomen'. The merits and disadvantages of using 'abdomen' as common synonym to more than one concept (polysemy) are briefly discussed and the solution adopted by SNOMED International described. The review of existing ontologies and academic literature confirmed the frequent varied use of the word 'abdomen', which raises concerns when derived data are increasingly being used remotely from the point of clinical contact, potentially leading to incorrect inferences. The documented regional truncal volumes from an anatomical regional, segmental and cross-sectional perspective have been integrated into a logical and comprehensive model suitable for computer processing. The robust modelling of meronymic hierarchies has to be rigorous to avoid systematic errors and it is thus timely that a proposed standard description of these subtly related volumes and structures is made available for discussion and comment.


Asunto(s)
Abdomen/anatomía & histología , Algoritmos , Estudios Transversales , Humanos , Systematized Nomenclature of Medicine
18.
Insect Sci ; 28(4): 965-975, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32452090

RESUMEN

The ladybird Harmonia axyridis is an insect that exhibits pupal attachment to plants, which facilitates development and environmental adaptation. The cremaster is highly specialized for this behavior. However, the underlying molecular regulation of the cremaster remains unclear; therefore, we performed experiments to investigate the transcriptional regulation of cremaster development. First, we examined the morphological structure of the cremaster to reveal its function in pupal attachment of H. axyridis. Next, we analyzed the Hox gene Ha-Abd-B using RNA interference (RNAi) to determine its function in regulating cremaster formation; Ha-Abd-B up-regulation promoted effective pupal attachment, whereas successful RNAi caused severe down-regulation of this gene, and pupae were unable to attach. Furthermore, successful RNAi and subsequent Ha-Abd-B down-regulation caused phenotypic changes in cremaster structure, including its complete disappearance from some individuals. Finally, we observed unique development of the cremaster and dynamic expression of Ha-Abd-B during pre-pupal development; consequently, we hypothesized that there was specific pre-pupal development of the cremaster. Overall, based on these results, the specialized cremasteric structure located on the posterior side of H. axyridis was determined to be a key organ for pupal attachment. Cremaster identification in H. axyridis is regulated by Ha-Abd-B and exhibits preferential development. Pupal attachment of H. axyridis reveals an environmental adaptation of this species; thus, this study and future molecular studies will help determine the role of Hox genes in regulation of insect attachment and further our understanding of the multiple functions of Hox genes.


Asunto(s)
Escarabajos , Proteínas de Homeodominio/genética , Abdomen/anatomía & histología , Animales , Escarabajos/anatomía & histología , Escarabajos/embriología , Escarabajos/genética , Escarabajos/fisiología , Regulación de la Expresión Génica , Larva/anatomía & histología , Larva/fisiología , Pupa/anatomía & histología , Pupa/fisiología , Interferencia de ARN
20.
Radiat Res ; 194(5): 544-556, 2020 11 10.
Artículo en Inglés | MEDLINE | ID: mdl-33045066

RESUMEN

Animal models of total-body irradiation (TBI) are used to elucidate normal tissue damage and evaluate the efficacy of medical countermeasures (MCM). The accuracy of these TBI models depends on the reproducibility of the radiation dose-response relationship for lethality, which in turn is highly dependent on robust radiation physics and dosimetry. However, the precise levels of radiation each organ absorbs can change dramatically when different photon beam qualities are used, due to the interplay between their penetration and the natural variation of animal sizes and geometries. In this study, we evaluate the effect of varying the radiation energy, namely cobalt-60 (Co-60); of similar penetration to a 4-MV polyenergetic beam), 6 MV and 15 MV, in the absorbed dose delivered by TBI to individual organs of eight Göttingen minipigs of varying weights (10.3-24.1 kg) and dimensions (17.5-25 cm width). The main organs, i.e. heart, lungs, esophagus, stomach, bowels, liver, kidneys and bladder, were contoured by an experienced radiation oncologist, and the volumetric radiation dose distribution was calculated using a commercial treatment planning system commissioned and validated for Co-60, 6-MV and 15-MV teletherapy units. The dose is normalized to the intended prescription at midline in the abdomen. For each animal and each energy, the body and organ dose volume histograms (DVHs) were computed. The results show that more penetrating photon energies produce dose distributions that are systematically and consistently more homogeneous and more uniform, both within individual organs and between different organs, across all animals. Thoracic organs (lungs, heart) received higher dose than prescribed while pelvic organs (bowel, bladder) received less dose than prescribed, due to smaller and wider separations, respectively. While these trends were slightly more pronounced in the smallest animals (10.3 kg, 19 cm abdominal width) and largest animals (>20 kg, ∼25 cm abdominal width), they were observed in all animals, including those in the 9-15 kg range typically used in MCM models. Some organs received an average absorbed dose representing <80% of prescribed dose when Co-60 was used, whereas all organs received average doses of >87% and >93% when 6 and 15 MV were used, respectively. Similarly, average dose to the thoracic organs reached as high as 125% of the intended dose with Co-60, compared to 115% for 15 MV. These results indicate that Co-60 consistently produces less uniform dose distributions in the Göttingen minipig compared to 6 and 15 MV. Moreover, heterogeneity of dose distributions for Co-60 is accentuated by anatomical and geometrical variations across various animals, leading to different absorbed dose delivered to organs for different animals. This difference in absorbed radiation organ doses, likely caused by the lower penetration of Co-60 and 6 MV compared to 15 MV, could potentially lead to different biological outcomes. While the link between the dose distribution and variation of biological outcome in the Göttingen minipig has never been explicitly studied, more pronounced dose heterogeneity within and between organs treated with Co-60 teletherapy units represents an additional confounding factor which can be easily mitigated by using a more penetrating energy.


Asunto(s)
Relación Dosis-Respuesta en la Radiación , Porcinos Enanos , Irradiación Corporal Total , Abdomen/anatomía & histología , Abdomen/efectos de la radiación , Absorción de Radiación , Animales , Tamaño Corporal , Peso Corporal , Radioisótopos de Cobalto , Rayos gamma , Masculino , Modelos Animales , Especificidad de Órganos , Aceleradores de Partículas , Pelvis/anatomía & histología , Pelvis/efectos de la radiación , Fotones , Posición Prona , Dosis de Radiación , Tolerancia a Radiación , Teleterapia por Radioisótopo/instrumentación , Planificación de la Radioterapia Asistida por Computador , Radioterapia de Alta Energía/instrumentación , Hombro/anatomía & histología , Hombro/efectos de la radiación , Porcinos , Porcinos Enanos/anatomía & histología , Tomografía Computarizada por Rayos X
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...