Morphometric method
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We test the hypothesis that living on larger fish may impose constraints, i.e. the need to develop large attachment organs, related to the necessity to remain attached on large gills. For this, we compiled data on body size and morphometric measurements of attachment organs of 44 Dactylogyrus species (ectoparasites with direct life-cycle) from 19 cyprinid species. Nineteen dactylogyrid species were considered as specialists (infecting only 1 host species) and 25 as generalists (infecting more than 1 species). The lack of phylogenetic information lead us to perform comparative analyses using raw values and independent contrasts obtained by random phylogenies. Our results show that rich parasite communities are formed by specialists and generalists whereas poor communities are composed mainly of generalist parasites. Moreover, specialists are found on larger hosts, which may reflect a specialization on a predictable resource, as larger fish live longer and offer large gills for parasite colonization. Parasite specialization is shown to be linked with adaptation of attachment organs to their fish hosts. Two morphometric variables of the attachment organ, the total length of anchor and length of base of anchor, were positively correlated with host length for specialists.
- MeSH
- druhová specificita MeSH
- fylogeneze MeSH
- infekce červy třídy Trematoda parazitologie veterinární MeSH
- infestace ektoparazity parazitologie veterinární MeSH
- interakce hostitele a parazita fyziologie MeSH
- máloostní parazitologie MeSH
- nemoci ryb parazitologie MeSH
- Trematoda anatomie a histologie parazitologie MeSH
- žábry parazitologie MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Česká republika MeSH
- Slovenská republika MeSH
Four new species of Ceratomyxa Thélohan, 1892 are described from the gall bladders of fishes collected off Lizard Island, Australia. These species are characterised using a combination of morphometric and molecular data. Ceratomyxa bartholomewae sp. n. is described from Hyporhamphus dussumieri (Valenciennes) (family Hemirhamphidae); C. koieae sp. n. is described from Sphyraena forsteri Cuvier (family Sphyraenidae); C. pantherini sp. n. is described from Bothus pantherinus (Rüppell) (family Bothidae) and C. reidi sp. n. is described from Chaetodon vagabundus Linnaeus (family Chaetodontidae). A fifth species from Zebrasoma veliferum (Bloch) (family Acanthuridae) is also reported but due to limited material is not formally described here.
- MeSH
- druhová specificita MeSH
- financování organizované MeSH
- fylogeneze MeSH
- Myxozoa cytologie genetika klasifikace MeSH
- nemoci ryb epidemiologie parazitologie MeSH
- parazitární nemoci u zvířat epidemiologie parazitologie MeSH
- ryby MeSH
- žlučník parazitologie MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Geografické názvy
- Austrálie MeSH
- Tichý oceán MeSH
Background: This study clarified some of anatomical relationships between the anterior clinoid process (ACP) and its surrounding structures, and identified a few major variations, important for clinical practice, especially for neurosurgeons in some skull base approaches to the cavernous sinus and paraclinoidal region lesions. Objective: The purpose of this paper is to show and prove morphometric variations of structures of sphenoid bone, the presence of caroticoclinoid foramen and types of ocular fissures and their practical significance primarily in neurosurgery in pituitary access and aneurysm surgery as well as comparison with other populations to prove the existence of difference between populations. Methods: By using classic anatomic methods-measurements 100 macerated and degenerated skulls were analyzed. With manual caliper, basal width, length and depth of anterior clinoid processes were measured. Furthermore, presence of different types of caroticoclinoid foramens, their diameters and presence of bone out-coming structures at the edges of superior orbital fissure (SOF) were analyzed. Results: We have found that optic strut (OS) was mainly adjusted in the first two fifths of the ACP (right side 42%, left 47.8%). We also noted that the basal width, length and depth of anterior clinoid process at the right side were 8.45±1.56 mm, 11.54 ±1.45 mm, 4.03±0.82 mm, and at the left side were 8.53±1.64 mm, 11.38±1.43 mm and 4.02±0.76 mm respectively. The greatest difference, due to sexes and side of skull, was presented with the incomplete type of caroticoclinoid foramen (CCF), which is much more frequent in males, placed to the right (39%) and to the left (31%). Same appearance at females is presented at the right side with 14% and at the left side with 9%. The average value of transversal foramen’s diameter was 3.55±2.55 mm. Conclusion: Incidence of appearance of interclinoid bone bridges in our study, on the sample of 100 skulls (200 sides) was 33% with significant difference between sexes. We used this sample to analyze the percent of different types of SOF in terms of analyzing the difference between sexes.
BACKGROUND AND PURPOSE: The primary objective was to compare diffusion tensor imaging (DTI) scalar parameters of peripheral nerves between subjects with type 2 diabetes mellitus (T2DM) and those without diabetes. Secondarily, we aimed to correlate DTI scalar parameters with nerve morphometric properties. METHODS: Median, tibial, and sural nerves were harvested from 34 male cadavers (17 T2DM, 17 nondiabetic). Each nerve was divided into three segments. The initial segment was scanned using 9.4 Tesla MRI system (three-dimensional pulsed-gradient spin-echo sequence). DTI scalars were calculated from region-average diffusion-weighted signals. Second segment was optically cleared, acquired with optical projection tomography (OPT), and analyzed for morphometrical properties. Toluidine-stained sections were prepared from last segment, and axon- and myelin-related properties were evaluated. RESULTS: DTI scalar parameters of median and tibial nerves were comparable between the groups, while sural nerves of T2DM exhibited on average 41% higher mean diffusivity (MD) (p = 0.03), 38% higher radial diffusivity (RD) (p = 0.03), and 27% lower fractional anisotropy (FA) (p = 0.005). Significant differences in toluidine-evaluated parameters of sural nerves were observed between the groups, with a positive correlation between FA with fiber density (p = 0.0001) and with myelin proportion (p < 0.0001) and an inverse correlation between RD and myelin proportion (p = 0.003). OPT-measured morphometric properties did not correlate with DTI scalar parameters. CONCLUSIONS: High-field DTI shows promise as an imaging technique for detecting axonal and myelin-related changes in small sural nerves ex vivo. The reduced fiber density and decreased myelin content, which can be observed in T2DM, likely contribute to observed FA reduction and increased MD/RD.
- MeSH
- diabetes mellitus 2. typu * diagnostické zobrazování patologie MeSH
- diabetické neuropatie diagnostické zobrazování patologie MeSH
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mrtvola * MeSH
- nervus medianus diagnostické zobrazování patologie MeSH
- nervus suralis * diagnostické zobrazování patologie MeSH
- nervus tibialis diagnostické zobrazování patologie MeSH
- reprodukovatelnost výsledků MeSH
- senioři MeSH
- senzitivita a specificita MeSH
- zobrazování difuzních tenzorů * metody MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři MeSH
- Publikační typ
- časopisecké články MeSH
Dimensions of periodontal tissues are thought to predispose to the development of periodontal disease in man and dogs. Several studies have suggested that thin gingiva correlates with an increased incidence of periodontal disease. In this study, we hypothesized that the dimensions of periodontal tissues will vary in different breeds of dogs and could possibly correlate with the incidence of periodontal disease. Forty-two jaws of dogs aged up to 5-years were examined post-mortem and gingival and alveolar bone thickness were measured using methods of transgingival probing and digital calipers, respectively. Dogs were divided into three groups based on their body weight. Group I (< 5.0 kg; n=21), group II (5 to 10 kg; n=11), and group III (10 to 15 kg; n=10). Thickness of gingiva ranged from 0.30-mm to 3.2-mm and was relatively thinner in group I than in group II and III based on the means of ratios comparison. Alveolar bone thickness ranged from 0.27-mm to 4.1-mm and was relatively thinner in group I compared with groups II and III. Our study showed significantly thinner gingiva and alveolar bone in toy breed dogs compared with small and medium-sized breed dogs. Both gingival and alveolar bone dimensions may be predictors for severity of periodontal disease and influence clinical outcome in certain periodontal surgical procedures.
- MeSH
- gingiva patologie MeSH
- kefalometrie přístrojové vybavení metody MeSH
- mandibula patologie MeSH
- maxila patologie MeSH
- mrtvola MeSH
- nemoci parodontu patologie veterinární MeSH
- nemoci psů patologie MeSH
- parodont patologie MeSH
- parodontologie přístrojové vybavení MeSH
- předpověď MeSH
- processus alveolaris patologie MeSH
- psi klasifikace MeSH
- tělesná hmotnost MeSH
- zubní oblouk patologie MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- psi klasifikace MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- srovnávací studie MeSH
Morphometric data from spores of ten myxosporean species were statistically analysed to explore myxosporean intraspecific variation in measurements when obtained from a sample from: (1) the same plasmodium, (2) different plasmodia from the same host and (3) different host individuals and localities. In some cases, significant differences in spore dimensions were found between samples from the same plasmodium, highlighting the difficulty of obtaining representative measurements of myxosporean spore. In addition, significant differences in spore dimensions were found when plasmodia from the same site of infection were compared, suggesting that measurements of spores should come from several different plasmodia of the sampling to increase the reliability of the morphology data. Moreover, significant differences in spore dimensions were observed for most spore dimensions when data were compared between localities. In all cases, there was clear overlap in ranges of dimensions even when means differed significantly. The present statistical analysis shows that intraspecific morphometric variation of myxosporean species commonly occurs, highlighting the importance of reporting ranges of measurements for a species, not just the mean dimensions, and taking into account all evidence when assigning or describing myxosporean species.
- MeSH
- druhová specificita MeSH
- fylogeneze MeSH
- Myxozoa klasifikace cytologie MeSH
- reprodukovatelnost výsledků MeSH
- spory cytologie MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
PURPOSE: To compare bony nasolacrimal duct anatomy between ethnic groups. METHODS: A retrospective observational study of patients of four ethnic groups who had high-resolution CTs between 2004 and 2019 covering the full length of their nasolacrimal ducts in two hospitals in Essex, England. Only normal ducts were included; patients with tearing or radiological abnormalities were excluded. Measurements were taken of the nasolacrimal duct and surrounding anatomy based on measurements found in the existing literature. RESULTS: More females (n = 114) than males (n = 40) were included. South Asian (Indian subcontinent), Afro-Caribbean and European groups were equivocal demographically (n = 25-29, mean age 40-45); however, the Oriental group was fewer in number (n = 13) and slightly older (mean age 51). South Asian and European ducts had no significant differences. Afro-Caribbean ducts were wider and shorter than European. Afro-Caribbean faces are wider and their noses flatter and wider than European. Oriental ducts were wider and longer than European, but Europeans have taller noses. CONCLUSION: The results from our Oriental group fits with the published data in Orientals. The bony nasolacrimal duct is greater in calibre (inner diameter) if the patient is of Afro-Caribbean or Oriental origin compared to European or South Asian. Acquired nasolacrimal duct obstruction in Afro-Caribbean or Oriental patients may be more likely due to secondary causes.
- MeSH
- Asijci MeSH
- dospělí MeSH
- ductus nasolacrimalis anatomie a histologie diagnostické zobrazování MeSH
- lidé středního věku MeSH
- lidé MeSH
- maxila anatomie a histologie diagnostické zobrazování MeSH
- mladiství MeSH
- mladý dospělý MeSH
- nosní skořepy anatomie a histologie diagnostické zobrazování MeSH
- obstrukce slzovodu etiologie MeSH
- počítačová rentgenová tomografie MeSH
- rasové skupiny MeSH
- retrospektivní studie MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladiství MeSH
- mladý dospělý MeSH
- mužské pohlaví MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- multicentrická studie MeSH
- pozorovací studie MeSH
- srovnávací studie MeSH
