scholarly journals Odontoameloblastoma with extensive chondroid matrix deposition in a guinea pig

2018 ◽  
Vol 30 (5) ◽  
pp. 793-797 ◽  
Author(s):  
Hannah E. Wong ◽  
Joanna Hedley ◽  
Nadene Stapleton ◽  
Brian Murphy ◽  
Simon L. Priestnall

Odontoameloblastomas (previously incorporated within ameloblastic odontomas) are matrix-producing odontogenic mixed tumors and are closely related in histologic appearance to the 2 other types of matrix-producing odontogenic mixed tumors: odontomas and ameloblastic fibro-odontomas. The presence or absence of intralesional, induced non-neoplastic tissue must be accounted for in the diagnosis. Herein we describe a naturally occurring odontoameloblastoma with extensive chondroid cementum deposition in a guinea pig ( Cavia porcellus). Microscopically, the mass featured palisading neoplastic odontogenic epithelium closely apposed to ribbons and rings of a pink dental matrix (dentinoid), alongside extensive sheets and aggregates of chondroid cementum. The final diagnosis was an odontoameloblastoma given the abundance of odontogenic epithelium in association with dentinoid but a paucity of pulp ectomesenchyme. Chondroid cementum is an expected anatomical feature of cavies, and its presence within the odontoameloblastoma was interpreted as a response of the ectomesenchyme of the dental follicle to the described neoplasm. Our case illustrates the inductive capabilities of odontoameloblastomas while highlighting species-specific anatomy that has resulted in a histologic appearance unique to cavies and provides imaging and histologic data to aid diagnosis of these challenging lesions.

2006 ◽  
Vol 19 (4) ◽  
pp. 728-762 ◽  
Author(s):  
Sue VandeWoude ◽  
Cristian Apetrei

SUMMARY Over 40 nonhuman primate (NHP) species harbor species-specific simian immunodeficiency viruses (SIVs). Similarly, more than 20 species of nondomestic felids and African hyenids demonstrate seroreactivity against feline immunodeficiency virus (FIV) antigens. While it has been challenging to study the biological implications of nonfatal infections in natural populations, epidemiologic and clinical studies performed thus far have only rarely detected increased morbidity or impaired fecundity/survival of naturally infected SIV- or FIV-seropositive versus -seronegative animals. Cross-species transmissions of these agents are rare in nature but have been used to develop experimental systems to evaluate mechanisms of pathogenicity and to develop animal models of HIV/AIDS. Given that felids and primates are substantially evolutionarily removed yet demonstrate the same pattern of apparently nonpathogenic lentiviral infections, comparison of the biological behaviors of these viruses can yield important implications for host-lentiviral adaptation which are relevant to human HIV/AIDS infection. This review therefore evaluates similarities in epidemiology, lentiviral genotyping, pathogenicity, host immune responses, and cross-species transmission of FIVs and factors associated with the establishment of lentiviral infections in new species. This comparison of consistent patterns in lentivirus biology will expose new directions for scientific inquiry for understanding the basis for virulence versus avirulence.


2006 ◽  
Vol 291 (2) ◽  
pp. H496-H506 ◽  
Author(s):  
Martina Krüger ◽  
Thomas Kohl ◽  
Wolfgang A. Linke

The giant protein titin, a major contributor to myocardial mechanics, is expressed in two main cardiac isoforms: stiff N2B (3.0 MDa) and more compliant N2BA (>3.2 MDa). Fetal hearts of mice, rats, and pigs express a unique N2BA isoform (∼3.7 MDa) but no N2B. Around birth the fetal N2BA titin is replaced by smaller-size N2BA isoforms and N2B, which predominates in adult hearts, stiffening their sarcomeres. Here we show that perinatal titin-isoform switching and corresponding passive stiffness (STp) changes do not occur in the hearts of guinea pig and sheep. In these species the shift toward “adult” proportions of N2B isoform is almost completed by midgestation. The relative contributions of titin and collagen to STp were estimated in force measurements on skinned cardiac muscle strips by selective titin proteolysis, leaving the collagen matrix unaffected. Titin-based STp contributed between 42% and 58% to total STp in late-fetal and adult sheep/guinea pigs and adult rats. However, only ∼20% of total STp was titin based in late-fetal rat. Titin-borne passive tension and the proportion of titin-based STp generally scaled with the N2B isoform percentage. The titin isoform transitions were correlated to a switch in troponin-I (TnI) isoform expression. In rats, fetal slow skeletal TnI (ssTnI) was replaced by adult carciac TnI (cTnI) shortly after birth, thereby reducing the Ca2+ sensitivity of force development. In contrast, guinea pig and sheep coexpressed ssTnI and cTnI in fetal hearts, and skinned fibers from guinea pig showed almost no perinatal shift in Ca2+ sensitivity. We conclude that TnI-isoform and titin-isoform switching and corresponding functional changes during heart development are not initiated by birth but are genetically programmed, species-specific regulated events.


2017 ◽  
Vol 65 (1) ◽  
pp. 89-95
Author(s):  
Gustavo A. Ramírez ◽  
Lorenzo Ressel ◽  
Jaume Altimira ◽  
Miquel Vilafranca

A 13-year-old male cat presented with an ill-defined mass in the rostral mandible causing destruction and loss of alveolar bone. Microscopically, the mass consisted of cords or islands of benign odontogenic epithelium and a malignant, pleomorphic spindle-shaped cell component with dysplastic dentine formation. Immunohistochemically, neoplastic mesenchymal cells proved to be strongly positive for vimentin and negative for cytokeratins, desmin, actin and S100 protein; the Ki67 proliferation index was high. Morphological and immunohistochemical features largely overlap those reported for ameloblastic fibrodentinosarcoma, an uncommon histologic subtype of odontogenic sarcoma recognised in humans but no reported previously in animals. Ki-67 expression assessment may help to discriminate between malignant and benign forms of odontogenic tumours but the final diagnosis is mainly morphological.


2015 ◽  
Vol 27 (3) ◽  
Author(s):  
Aris Munandar ◽  
Endang Syamsudin ◽  
Melita Sylvyana ◽  
Kiki Akhmad Rizki

Background. Adenomatoid Odontogenic Tumor (AOT) is a rare tumor of epithelial origin. AOT appears in three clinico-topographic variants: follicular, extrafollicular and peripheral. The AOT was predominantly found in the upper jaw, and rarely found in mandible, especially at anterior mandible. AOT is a tumor of odontogenic epithelium having duct like structures, which may be partly cystic, and in some cases the solid lesion may be present only as masses in the wall of a large cyst. The surgical management of this lesion would be enucleation along with removal of associated impacted tooth. The prognosis for both of them is good and recurrences are very rare after complete removal of the lesion. Purpose. It is important to define final diagnose for AOT due to mimicking with DC in clinically and radiographically finding. Biopsy is still obviously necessary to the final diagnosis. Case. 15-year-old female patients reported with chief complain of swelling in anterior mandible. The swelling beginning 4 years ago, gradually progressed, with no history pain, discharge and patient is complaint about loss of sensation around anterior mandible. Aspiration revealed straw colored fluid thinking in the way of DC. The provisional diagnosis of DC was given due to clinical presentation and radiographic imaging. But the biopsy examination showed AOT due to duct-like epithelial cells was being found. Discussion. The case report illustrates characteristic clinical and radiographic features of follicular variant of AOT mimicking a DC at unusual site that is anterior mandible. AOT is thought to arise from odontogenic epithelium and associated with the impacted tooth. Rightfully AOT is a perfect imitator of DC radiographically as well as histopathologically. It usually clinically misdiagnosed as DC as both have a unilocular, well-defined radiolucency surrounding the crown of an impacted tooth. The mass was enucleated, involved teeth were extracted, and titanium plates are used to avoid pathologist fracture. The patient had uneventful postoperative recovery. Follow up of a year has not shown any evidence of recurrence. Conclusion. Follicular type of OAT could confuse us with DC if the support examination just only clinicaly finding and radiographic examination. This case could not be definitively diagnosed on clinical and radiographic features alone. Biopsy was obviously necessary to the final diagnosis.


1930 ◽  
Vol 13 (3) ◽  
pp. 307-316 ◽  
Author(s):  
Alden Kinney Boor

1. Photomicrographs of crystals of pure carbonmonoxide hemoglobin of the following species are presented; ox, sheep, hog, dog, turkey, rat, horse, chicken and guinea pig. Photomicrographs of the oxyhemoglobin crystals of the following species are also shown: ox, sheep, hog, dog, rat, horse and guinea pig. The crystals were formed from the pure protein by adding a suitable amount of ethyl alcohol and maintaining a temperature of 0°C., or lower. 2. In some species a sufficient difference is shown between the carbonmonoxide hemoglobin and oxyhemoglobin crystals to distinguish these compounds, but the photographs of crystals of carbonmonoxide hemoglobin and oxyhemoglobin of some species, such as guinea pig, show no appreciable difference. 3. Differences between the carbonmonoxide hemoglobins, as well as between the oxyhemoglobins, of the different species studied are indicated. 4. The carbonmonoxide hemoglobin crystals from the bloods studied are species specific in their nature, and, in many cases, can be distinguished from the analogous oxyhemoglobin by crystallographic study.


1986 ◽  
Vol 237 (2) ◽  
pp. 469-476 ◽  
Author(s):  
K L LaMarco ◽  
R H Glew

We have isolated from guinea-pig liver a broad-specificity beta-glucosidase of unknown function that utilizes as its substrate non-physiological aryl glycosides (e.g. 4-methylumbelliferyl beta-D-glucopyranoside, p-nitrophenyl beta-D-glucopyranoside). The present paper documents that this enzyme can be inhibited by various naturally occurring glycosides, including L-picein, dhurrin and glucocheirolin. In addition, L-picein, which acts as a competitive inhibitor of the broad-specificity beta-glucosidase (Ki 0.65 mM), is also a substrate for this enzyme (Km 0.63 mM; Vmax. 277,000 units/mg). Heat-denaturation, kinetic competition studies, chromatographic properties and pH optima all argue strongly that the broad-specificity beta-glucosidase is responsible for the hydrolysis of both the non-physiological aryl glycosides and L-picein. This paper demonstrates that beta-glucosidase can catalyse the hydrolysis of a natural glycoside, and may provide a key to understanding the function of this enigmatic enzyme. A possible role in the metabolism of xenobiotic compounds is discussed.


Forests ◽  
2020 ◽  
Vol 11 (8) ◽  
pp. 844 ◽  
Author(s):  
Ai-Ying Wang ◽  
Guang-You Hao ◽  
Jing-Jing Guo ◽  
Zhi-Hui Liu ◽  
Jiao-Lin Zhang ◽  
...  

Adaptation and acclimation of tree seedlings to different combinations of light and water conditions can determine the species-specific patterns of distribution along environmental gradients and the underlying physiological mechanisms are fundamental to the understanding of such patterns. Seedlings of two Cyclobalanopsis species naturally occurring in southwest China, with distinct distribution and regeneration characteristics, were grown under 100%, 50% and 4% sunlight conditions and traits related to shade and drought tolerance were studied. Particularly, we investigated whether leaf hydraulics, photosynthetic traits and their functional coordination play an important role in determining seedling environmental adaptation and acclimation of the two species. Seedlings of C. helferiana showed characteristics adapted to high irradiance while C. rex had traits adapted to partially shaded environments. Cyclobalanopsis helferiana had significantly higher maximum net photosynthetic rate (Amax), light compensation point and light saturation point than C. rex and the contrasts were particularly large when they were grown under full sunlight. Cyclobalanopsis helferiana showed the highest Amax when grown under 100% sunlight, while C. rex exhibited the highest Amax at 50% sunlight. Similarly, under full sunlight conditions C. helferiana showed significantly higher leaf hydraulic conductance (Kleaf) than C. rex, i.e., 13.37 vs. 7.09 mmol m−2 s−1 MPa−1 (p < 0.01). The correlation between Kleaf and Amax followed a unified positive correlation across different light treatments of both species. Moreover, leaves of C. helferiana showed greater resistance to drought-induced hydraulic dysfunction and to desiccation than C. rex. The contrasts in functional traits between the two Cyclobalanopsis species are consistent with the hypothesis that there is a trade-off between shade tolerance and drought tolerance. Findings of the present study contribute to a deeper understanding of mechanisms of divergence between closely related (congeneric) species with respect to key ecophysiology associated with natural regeneration.


2017 ◽  
Vol 91 (19) ◽  
Author(s):  
Kayla M. Peck ◽  
Trevor Scobey ◽  
Jesica Swanstrom ◽  
Kara L. Jensen ◽  
Christina L. Burch ◽  
...  

ABSTRACT Middle East respiratory syndrome coronavirus (MERS-CoV) utilizes dipeptidyl peptidase 4 (DPP4) as an entry receptor. While bat, camel, and human DPP4 support MERS-CoV infection, several DPP4 orthologs, including mouse, ferret, hamster, and guinea pig DPP4, do not. Previous work revealed that glycosylation of mouse DPP4 plays a role in blocking MERS-CoV infection. Here, we tested whether glycosylation also acts as a determinant of permissivity for ferret, hamster, and guinea pig DPP4. We found that, while glycosylation plays an important role in these orthologs, additional sequence and structural determinants impact their ability to act as functional receptors for MERS-CoV. These results provide insight into DPP4 species-specific differences impacting MERS-CoV host range and better inform our understanding of virus-receptor interactions associated with disease emergence and host susceptibility. IMPORTANCE MERS-CoV is a recently emerged zoonotic virus that is still circulating in the human population with an ∼35% mortality rate. With no available vaccines or therapeutics, the study of MERS-CoV pathogenesis is crucial for its control and prevention. However, in vivo studies are limited because MERS-CoV cannot infect wild-type mice due to incompatibilities between the virus spike and the mouse host cell receptor, mouse DPP4 (mDPP4). Specifically, mDPP4 has a nonconserved glycosylation site that acts as a barrier to MERS-CoV infection. Thus, one mouse model strategy has been to modify the mouse genome to remove this glycosylation site. Here, we investigated whether glycosylation acts as a barrier to infection for other nonpermissive small-animal species, namely, ferret, guinea pig, and hamster. Understanding the virus-receptor interactions for these DPP4 orthologs will help in the development of additional animal models while also revealing species-specific differences impacting MERS-CoV host range.


Antibodies from immune serum ingested by suckling mice and rats may enter into their circulations. The normal sera of certain species, when mixed with the immune serum administered, reduce the entry of antibodies. This effect was called interference. Interference with the uptake of guinea-pig agglutinins in mice due to rabbit serum and γ-globulin and to fragments I, II and III of rabbit γ-globulin, fractionated by the digestion method of Porter, is investigated. The effect of rabbit serum is due mostly, if not wholly, to its γ-globulin. Interference due to fragments I and II is negligible, whereas interference due to fragment III is at least 3.5 times greater than that due to the whole γ-globulin molecule. It is concluded that most of the configurations of the whole rabbit γ-globulin molecule which are recognized by mouse cells as heterologous are carried on fragment III. A hypothesis, which postulates a specific receptor within absorptive cells concerned with the transmission of antibodies across the gut of some young rodents, is discussed in the light of these results, when it is suggested that the receptor may be better adapted to receive the species-specific parts of antibody molecules rather than the residual or antibody reactive parts.


Sign in / Sign up

Export Citation Format

Share Document