Sharp Teeth Research Articles

Traumatic ulcerative granuloma with stromal eosinophilia: a series of four cases with review of literature

Most of the oral ulcers are traumatic in origin due to sharp tooth and self bite. Traumatic ulcerative granuloma with stromal eosinophilia is a chronic benign lesion of the oral mucosa with uncertain histogenesis. Trauma was proposed to be an inciting factor.
 A series of four cases of Traumatic Ulcerative Granuloma with Stromal Eosinophilia in the lateral borders of the tongue were analyzed regarding oral hygiene, sharp tooth, clinical presentation, histology, and follow-up. The lesion manifests as a small solitary ulcer with induration in the oral mucosa mimicking malignancy. Histology revealed ulcers with exudate and granulation tissue with dense polymorphous infiltrate rich in eosinophils. Infiltrate extends down in between the skeletal muscle fibers and salivary gland lobules. A sharp tooth was found to be the inciting factor in a proportion of cases. Histopathological examination is mandatory to confirm the diagnosis and to exclude malignancy and other eosinophil rich disorders.

Cytogenetic analysis of genetic damage in young individuals exposed to chronic mechanical irritation in the lateral border of the tongue due to sharp teeth - a novel study.

BackgroundChronic inflammation is estimated to contribute to approximately 25% of human cancers. Inflammation can be induced by chronic mechanical irritation which can lead to oral pre-cancer and oral cancer. Though many studies have been conducted to identify the genetic damage in oral cancer or dysplastic stages, no study has been conducted so far on early detection of genetic damage in healthy individuals presenting with sharp teeth in contact with the lateral border of the tongue.ObjectiveThe study is aimed at analyzing the genetic damage (micronuclei) in healthy individuals with sharp teeth in contact with the lateral border of the tongue causing chronic mechanical irritation.MethodsThe study group included 75 clinically healthy individuals with sharp teeth in contact with the lateral border of the tongue and 25 clinically healthy individuals with normal teeth in contact with the lateral border of the tongue as a control group. Brush samples of epithelial cells were collected, then spread over clean glass slide and fixed in 100% alcohol, stained with rapid PAP and analyzed under the light microscope. The exfoliated cells were examined to detect micronuclei.ResultsMicronuclei frequency was found to be increased in the study group where sharp teeth were in contact with the lateral border of the tongue of healthy individuals without deleterious habits such as usage of tobacco in smoking/smokeless form, areca nut chewing or alcohol consumption.ConclusionsCytogenetic analysis is a simple and scantly invasive technique allowing clinicians the early detection of DNA damage in patients with sharp teeth and subsequently preventing carcinogenesis by proper treatment and follow-up.

Cadmium and lead levels in three freshwater fish species from the Zambezi region, Namibia

Muscle tissue from three-spotted tilapia (Oreochromis andersonii) (n = 11), sharp tooth catfish (Clarias gariepinus) (n = 14) and tigerfish (Hydrocynus vittatus) (n = 12) were sampled from a market in the Zambezi region, Namibia in June 2018 and analysed for cadmium and lead. Cadmium was not detected in the three fish species. Mean lead levels in all three fish species (0.09–0.19 mg kg−1) were below the recommended safe level of 0.3 mg kg−1. Catfish had the highest mean lead concentrations, followed by tigerfish and tilapia in descending order. However, the differences in mean lead concentrations between the three fish species were not statistically significant (ANOVA, p = 0.18). These results show that the fish tested were safe for human consumption with respect to the metals tested. It is recommended that more metals and other contaminants, such as pesticides, be monitored robustly in water, sediment and fish, using the recommended protocols, in order to generate data that can be reliably used for human health risk assessments in the future.

FUNCTIONING OF THE SPEECH CONSTITUENTS OF THE LEXICAL SEMANTIC FIELD “FACE” IN BRAM STOCKER’S NOVEL DRACULA

In this article we consider the way the speech variant of the lexical semantic field FACE functions in the novel by Br. Stocker “Dracula”, the precedent text in vampire literature. We focus on the depiction of the vampire characters to identify the set of typical traits as they are represented in the novel, special attention is paid to the traits attributed to Count Dracula. We adopt the definition of the portrait offered by Elena Kalinjuk, where portrait description is understood as a variation of the compositional speech forms “description” which studies a literary character, his/her appearance, clothes, manners, speech and psychoemotional behavior. In our article we have analysed physiognomy and countenance proceeding from the fact that the constituent elements of the lexical semantic field FACE denote face with its parts and facial expressions. The latter describe emotional experience and act as means of nonverbal communication. The detailed portrait description prevails in our selection of 102 portrait descriptions. All the constituent elements of the LSF FACE are classified according to the parts of the face they denote. As a result, we’ve obtained seven groups, the most frequently used constituent elements indicate the following parts of the face: “mouth”, “face proper” and “eyes”. Some of the specific traits are foregrounded through the distant repetition of the lexical units. These traits have become the descriptive details in the novel, they are “red lips”, “peculiarly sharp white teeth”, “burning eyes”, “sharp aquiline nose”, “the scar on the forehead”. All the constituent elements of the LSF FACE represent the conceptual opposition FRIEND-ENEMY.

A new genus and species of pilumnid crab (Decapoda: Brachyura: Pilumnidae) symbiotic with the spongeCallyspongiaDuchassaing & Michelotti, 1864 (Porifera: Demospongiae: Callyspongiidae) from Lombok, Indonesia; the identity ofPseudactumnus pestaeBalss, 1933; and a review of symbiosis in the Pilumnidae

AbstractA new genus and new species of pilumnid crab, Ericiolumnus symbioticus (Decapoda: Brachyura), is described from the sponge Callyspongia Duchassaing & Michelotti, 1864 (Porifera: Callyspongiidae) in reefs in Lombok, Indonesia. The new taxon is characterized, among several characters, by the unusual shape of the carapace, which possesses sharp anterolateral teeth armed with secondary spinules, and prominently spinulous ambulatory legs. Another pilumnid, Pseudactumnus pestaeBalss, 1933, is shown to be a junior synonym of Actumnus asper (Rüppell, 1830). The pilumnid genus PseudactumnusBalss, 1933 is additionally synonymised with ActumnusDana, 1851. A review of symbiosis in Pilumnidae is also presented.

Stiffness distribution in natural insect cuticle reveals an impact resistance strategy

In nature, many insects have evolved hard cuticles to shelter their soft body, which is thought to be the “body-armour” for insects to protect against predators' sharp teeth or dynamic load damage caused by harsh environments. In recent years, researchers have found that the “body-armour” is composed of multi-layer materials with different elastic modulus from inside to outside. The gradient change rule of the formed material modulus reflects the evolutionary history of insect cuticle's adaptation to external changes. In this article, the mechanical properties of spatial hierarchical architecture of insect cuticle, especially for the shield-like beetle elytra under impact loading, was investigated to reveal the impact resistance strategy and in-depth mechanisms of crashworthy protection. The results show that both discontinuity at the cuticle layers interface and the distributions of stiffness gradients through layers’ thickness have a great influence on preventing stress wave propagation and improving impact-tolerance. Insect cuticle such as beetle elytra with discontinuous exponential stiffness gradient (DC-EXP) along the thickness has been identified to result in the minimum values of stress and interaction force under impact loading, which leads to the best impact resistance property and defensive effect. Furthermore, we compared and discussed the protective properties of insect elytra with different sclerotized endocuticle under quasi-static compression and impact loading, respectively. The knowledge gained from this work reveals the advantages of nature’s choice of the stiffness distribution and may serve to inspire further research of developing advanced multifunctional structures with improved impact resistance capability by programming reasonable stiffness distribution.

Tooth-shape adaptations in aglyphous colubrid snakes inferred from three-dimensional geometric morphometrics and finite element analysis

AbstractTo date there are few quantitative studies investigating the evolution of tooth shape and function in aglyphous snakes in relation to diet. A considerable evolutionary decrease in body size is observed in whip snakes of the genus Dolichophis and their sister-group Eirenis. This was coupled with a considerable shift in diet from a regime consisting mainly of prey with endoskeleton to prey bearing a hard exoskeleton. Three-dimensional (3D) geometric morphometrics revealed that the maxillary and palatine teeth of E. persicus are blunt and conical in shape, while the same teeth are sharp and elongated in E. punctatolineatus and D. schmidti. Blunt and conically shaped teeth, as observed in E. persicus, seem to be more adapted for biting hard-bodied, arthropod prey. In contrast, the sharp and elongated teeth in Dolichophis and E. punctatolineatus, are likely specialized for puncturing prey with an endoskeleton. The results of a finite element analysis confirms that during the biting of a hard-bodied prey, the generated stresses in E. persicus teeth are well below the von Mises yield criterion, while in D. schmidti the value is roughly two to three times higher, indicating that E. persicus teeth are better suited for biting hard-bodied prey such as arthropods.

A new stem-neopterygian fish from the Middle Triassic (Anisian) of Yunnan, China, with a reassessment of the relationships of early neopterygian clades

AbstractNeopterygii is a taxonomically diverse group of ray-finned fishes, including Teleostei, Holostei and their closely related fossil taxa. Here, a new small-sized stem-neopterygian with extraordinarily long teeth, Louwoichthys pusillus gen. et sp. nov., is described based on 14 well-preserved specimens from the Middle Triassic (Anisian) marine deposits of Yunnan, China. Louwoichthys is closely related to Luopingichthys from the same fossil beds and Ctenognathichthys from the Middle Triassic of the Monte San Giorgio area in Europe; the three genera are grouped into the family Louwoichthyidae fam. nov., which is recovered as sister to the ‘perleidiform’ Pseudobeaconiidae. Given that ‘Perleidiformes’ is notoriously paraphyletic, a new order, Louwoichthyiformes ord. nov., is introduced to group both families. The louwoichthyiform monophyly is strongly supported by a series of derived features, such as a relatively short maxilla, an anteriorly inclined preopercle, a subopercle with a prominent anteroventral extension, and two or three pairs of branchiostegal rays. Louwoichthys is one of the smallest louwoichthyiforms, having a largest standard length of 39 mm. It is deduced to be a scavenger that might use its long and sharp teeth to grasp and tear the prey from the substrate or to bite a piece from a larger prey item.

Adaptive neuro-fuzzy prediction of operation of the bucket wheel drive based on wear of cutting elements

The capacity of the rotor excavator depends largely on the operation of the subsystem for digging. There is a great contribution to the correct and sharp teeth when the capacity is the highest. In the function of time, the teeth become clogged due to abrasive wear, or changes in their geometric shape. To analyze the bucket wheel drive in depend on wear of the cutting elements in this study adaptive neuro fuzzy inference system (ANFIS) approach was implemented. ANFIS is a type of artificial neural network combined with fuzzy logic inference which is suitable for nonlinear data samples. The main goal of the study was to establish dependence on how the wear of cutting elements affects the operation of the bucket wheel drive. According to the results prediction of the horizontal frequency has the highest accuracy (R2= 0.7612, r = 0.8724, RMSE = 91.4881). Combining specific energy consumption and vibration on the input pair of the shaft would make a major step forward from existing scientific knowledge.

First Mexican species of Pseudachorudina (Collembola: Neanuridae: Pseudachorutinae) from Mapimí Desert, State of Durango

Pseudachorudina navarretei sp. nov. from Mapimi Desert, Durango, Mexico, is described. It is similar to the American species P. texensis and P. ignotus Christiansen and Bellinger, 1980, all of them with 1 dorsal strong capitated tenent hair on tibiotarsi. It differs in the shape of the maxillary lamellae, one with 4 sharp big teeth and one semispherical with 5 stocky teeth while P. texensis has both lamellae toothed and similar; P. ignotus has only 1 serrate lamella and the maxillary capitulum is elongated. The new species has 5 long dental setae; P. texensis has 4 short and P. ignotus has 6 of different sizes.

Species specificity and sexual dimorphism in tooth shape among the three sympatric haplochromine species in Lake Kivu cichlids.

Tooth shape is used to differentiate between morphologically similar species of vertebrates, including fish. This study aimed to quantify tooth shape of three sympatric species: Haplochromis kamiranzovu, H. insidiae, and H. astatodon endemic to Lake Kivu, whose existing identification criteria are currently only qualitative. A quantitative tooth shape analysis was performed based on digitized tooth outline data with a subsequent elliptic Fourier analysis to test for differences among the three species. We looked at crown shape and size differences within H. kamiranzovu and H. insidiae at geographical, habitat, and gender levels. No comparison at habitat level was done for H. astatodon because it is found only in littoral zone. The analysis revealed significant tooth shape differences among the three species. Haplochromis astatodon had a significantly longer major cusp height and a longer and larger minor cusp than that of H. insidiae. It had also a longer major cusp height and a longer and larger minor cusp than that of H. kamiranzovu. Tooth shape differences of H. kamiranzovu and H. insidiae species were not significantly different between littoral and pelagic fish (p > .05) while differences were significant between southern and northern Lake Kivu populations (p < .05). Tooth sizes in H. kamiranzovu and H. insidiae were significantly different, both in height and width as well as in their ratios, and this was true at sex and geographic levels (p < .05), but not at habitat level (p > .05). Tooth shape was also significantly different with sharp teeth for males compared with females of southern populations versus northern ones. These shape‐ and size‐related differences between sexes suggest differences in the foraging strategies toward available food resources in the lake habitat. Further research should explain the genetic basis of the observed pattern.

Multifunctional mandibles of ants: Variation in gripping behavior facilitated by specific microstructures and kinematics

The elongated mandibles of certain ant species are dexterous grippers that can output a wide range of forces as needed for various tasks. Our combined experimental and theoretical research reveals the multifunctionality of the mandibles of Harpegnathos venator that is facilitated by specific microstructures and characteristic kinematics. First, we found that H. venator can pull off a spider’s (Heteropoda venatoria) leg by closing its long mandibles. We observed that the ant usually clamps the spider’s leg using the distal or middle part of its mandibles. In contrast, the ant can grip its egg with the proximal parts of its mandibles without causing damage. Our results showed that the spider’s legs are always fractured at the coxa-trochanteral joint. Second, we found that the force required to fracture the spider’s leg can be up to 500 times the ant’s body weight. On the other hand, the maximum force can be controlled to less than 2×10- 6N while gripping an egg. By combining microstructure imaging, kinematic tracking and mathematical modeling, we uncovered that the sharp teeth and dense bristles on the internal side of the mandibles determine the high adhesion force, while the concave teeth and biaxial rotation of the mandibles facilitate gentle gripping. We validated our findings by constructing an artificial mandible pair. This work expands the knowledge of the physiological multifunctionality in ant mandibles, and provides novel ways to reveal the multifunctionality in insect appendages by applying the tools of mechanical analysis and related experimental devices.

Early evolution of Cupedidae revealed by a mid‐Cretaceous reticulated beetle from Myanmar (Coleoptera: Archostemata)

AbstractCupedidae, the most species‐rich family of the archaic suborder Archostemata, were abundant, diverse and widespread in the Mesozoic, yet little is known about the early evolution and biogeography. This stems, in part, from a lack of exceptionally preserved fossils from the Mesozoic and of formal phylogenetic study of both extant and extinct taxa. Here we describe and illustrate a new fossil from mid‐Cretaceous Burmese amber, and provide a phylogeny combining both fossils and all known extant genera of Archostemata. A dataset of 43 ingroup taxa and four outgroup taxa based on 110 morphological characters was analysed under parsimony. The results indicate that Priacma LeConte and Paracupes Kolbe, as well as the Cretaceous genera Barbaticupes Jarzembowski et al. and Mallecupes Jarzembowski et al., together form a sister clade to the rest of Cupedidae. Priacma megapuncta sp.n. is attributed to the relict North American Priacma by the presence of distinct subtruncate elytral apices, lateral elytral margins with two rows of sharp teeth, and peculiar fixing epipleural folds near the elytral apices. Our discovery of the first fossil species of Priacma in Burmese amber reveals the antiquity and wider distribution of the genus in the late Mesozoic.This published work has been registered in ZooBank, http://zoobank.org/urn:lsid:zoobank.org:pub:313565C2‐4F42‐48BD‐8720‐F379DE202868.

A new species of freshwater crab of the genus Mediapotamon Türkay & Dai, 1997 (Crustacea, Decapoda, Brachyura, Potamidae) from Guizhou, China.

A new species of Mediapotamon Türkay & Dai, 1997 from a karst system in southwest China is described. The new species can be separated from congeners by the combination of a sharp and distinct epibranchial tooth, the anterolateral region lined with few scattered granules, the terminal segment of the male first gonopod distinctly bent with a constant diameter, and the position of the female vulvae. Mitochondrial 16S rDNA genetic data was used to investigate the systematic position of the new species, which is supported as a new taxon.

Wouldn't it, too, be nice?

Wouldn't it, too, be nice?

Two new species of Lejeuneaceae tribe Lejeuneeae (Marchantiophyta) from Colombia

Abstract We describe the new liverwort species Lejeunea ryszardii from montane rainforest in the Central Cordillera of Colombia (Dept. Quindío) and Rectolejeunea halinae from submontane rainforest in the Western Cordillera (Dept. Risaralda). Both species stand out by copious vegetative reproduction via caducous leaves. Lejeunea ryszardii resembles the Caribbean L. paucidentata in the leaf lobes with toothed margins and a narrow base but strikingly differs from the latter species in: 1) leaf margins with mamillose cells, which are sometimes crowned by a small papilla, and with scattered rhizoids with or without a tooth-like base; 2) lobules with narrowly elongate, curved, sharp tooth; 3) stem epidermis brownish and somewhat thick-walled; 4) copious production of caducous leaf lobes. Moreover, L. ryszardii is dark green to brown in color and probably dioicous while L. paucidentata is light green and autoicous. Rectolejeunea halinae resembles the neotropical R. flagelliformis in having ciliate caducous leaves but clearly differs from the latter in the pointed leaf tips, the presence of ocelli in underleaves, and the flagelliform shoots with flat, entire-margined underleaves. The discovery of these new species adds two further endemic taxa to the rich bryophyte flora of the Colombian Andes.

People who saw dark, fat devils with sharp teeth and bulging eyes – Charles Bonnet syndrome: a case series

The Sri Lanka Journal of Psychiatry (SLJP) is a peer-reviewed, open access journal published bi annually by the Sri Lanka College of Psychiatrists.The Journal publishes original papers, brief reports including case reports and commentaries relevant to psychiatry and allied sciences. The Sri Lanka Journal of Psychiatry is committed to maintaining and conforming to the editorial and ethical standards recommended by the International Committee of Medical Journal Editors.Cover: Doorways: When one is ill, having somewhere to stay, where one is looked after, is usually a relief to the patient who is not well and his/her family. The picture shows the doorway to what remains of an ancient hospital in Mihintale, said to date back two millennia. Thilini Rajapakse, Department of Psychiatry, Faculty of Medicine, University of Peradeniya, Sri Lanka.

Antiquarianism as a Vital Historiography for the Twenty-First Century

Antiquarianism as a Vital Historiography for the Twenty-First Century

A Taphonomic Study of Crocodylus porosus (Crocodylidae) and Tomistoma schlegelii (Gavialidae) Remains from Western Sarawak, Malaysian Borneo: Applications for Public Education

This study documented details of the dentitions, skulls and other skeletal remains of Crocodylus porosus and Tomistoma schlegelii, from western part of Sarawak, Malaysian Borneo. The remains of both reptiles were exhumed, followed by standard cleaning procedures and then detail morphological assessments were carried out accordingly. Both species show similar structure of vertebral columns, but T. schlegelii has the following unique structures: a long and narrower snout, D-shaped eye sockets, long and sharp pointed protruding quadratojugal bones, straight maxillae and dentary, a smooth surfaced skull, elongated triangular suborbital fenestrae, round shaped internal nares and visible supraoccipital from a dorsal view. C. porosus has heterodont dentition with blunt-pointed and irregular size of teeth whereas T. schlegelii has almost homodont dentition with sharp and similar size teeth. This is the first collection of teeth, skulls and other skeletal remains of both species obtained from Sarawak, and the materials have been used regularly to educate the public through science exhibitions, hoping they will spark the interests of young budding scientists to be involved in wildlife taphonomic studies in the future.Keywords: Crocodylus porosus, dentition, reptile, skeletal remain, Tomistoma schlegelii

Larval development of Brycon amazonicus (Teleostei, Bryconidae) with a focus on locomotory, respiratory and feeding structures.

In the present work we describe the larval development of Brycon amazonicus, with emphasis on structures linked to swimming, respiration and feeding. We monitored from larval hatching (13 h post-fertilization) to juvenile stage. Formation of the oral cavity and differentiation of gill arches began within 4 h post-hatching (hph) and within 11 hph the primordium of the pectoral fin appeared. At 25 hph, the head was in a rectilinear position with a terminal mouth, when the onset of tooth formation appeared. At 35 hph, gill arches were covered by the operculum and branchiostegal membrane and cusps of teeth pierced the epithelium of the premaxilla and anterior dentary region. Sharp teeth were observed in the maxilla at 171 hph and the pelvic fin primordium appeared at 243 hph, with taste buds on the tongue and the roof of the buccopharyngeal cavity. At 579 hph, all structures related to swimming and food capture were formed. Exogenous feeding of the larvae started at 29 hph, before the endogenous reserves were used up and the development of efficient swimming ability, reflecting the species' need to increasingly specialize on prey capture.