Palpitations Revealing a Primary Pulmonary Artery Sarcoma.

Primary pulmonary artery sarcoma is an exceedingly rare and aggressive malignancy that carries poor prognosis. Clinical manifestations are nonspecific and include chest pain, dyspnea, syncope, palpitations, and asthenia, among others. Delay to diagnosis is common and compromises the prognosis. Here, we report an interesting case of primary pulmonary artery sarcoma presenting with frequent monomorphic premature ventricular contractions arising from the right/left ventricle outflow tract. Cardiac imaging is key in the evaluation of patients with frequent premature ventricular contractions to rule out rare pathologies such as tumour compression.

Le sarcome primaire de l'artère pulmonaire est une tumeur maligne extrêmement rare et agressive de mauvais pronostic. Les manifestations cliniques sont non spécifiques et peuvent inclure de la douleur thoracique, de la dyspnée, des syncopes, des palpitations et de l'asthénie. Le retard diagnostic est fréquent et compromet le pronostic. Nous rapportons ici un cas intéressant de sarcome primaire de l'artère pulmonaire pour lequel le patient présentait des extrasystoles ventriculaires prématurées monomorphes qui provenaient des chambres de chasse des ventricules gauche et droit. L'imagerie est essentielle à l'évaluation des patients présentant de fréquentes extrasystoles ventriculaires afin d'écarter des pathologies rares comme la compression tumorale d'une chambre cardiaque.

Mesenchymal chondrosarcoma of the orbit masquerading as a hemophilic pseudotumor.

An 11-year-old boy presented with a lesion of the right orbit that was thought to be a hemophilic pseudotumor. Excisional biopsy revealed an unexpected diagnosis of mesenchymal chondrosarcoma. Both mesenchymal chondrosarcoma and hemophilic pseudotumor of the orbit are exceedingly rare. To the best of our knowledge, this is the first reported case of orbital mesenchymal chondrosarcoma masquerading as hemophilic pseudotumor.

Inflammation and Hypervascularization in a Large Animal Model of Knee Osteoarthritis: Imaging with Pathohistologic Correlation.

PURPOSE: To evaluate if synovial inflammation and hypervascularization are present in a dog model of knee osteoarthritis and can be detected on conventional magnetic resonance imaging (MRI), dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI), contrast-enhanced magnetic resonance imaging (CE-MRI), and quantitative digital subtraction angiography (Q-DSA) imaging. MATERIALS AND METHODS: Six dogs underwent MRI and angiography of both knees before and 12 weeks after right knee anterior cruciate ligament injury. Synovial vascularity was evaluated on CE-MRI, DCE-MRI, and Q-DSA by 2 independent observers. Synovial inflammation and vascularity were histologically scored independently. Cartilage lesions and osteophytes were analyzed macroscopically, and cartilage volumetry was analyzed by MRI. Vascularity and osteoarthritis markers on imaging were compared before and after osteoarthritis generation, and between the osteoarthritis model and the control knee, using linear mixed models accounting for within-dog correlation. RESULTS: In all knees, baseline imaging showed no abnormalities. Control knees did not develop significant osteoarthritis changes, synovial inflammation, or hypervascularization. In osteoarthritis knees, mean synovial enhancement score on CE-MR imaging increased by 13.1 ± 0.59 (P < .0001); mean synovial inflammation variable increased from 47.33 ± 18.61 to 407.97 ± 18.61 on DCE-MR imaging (P < .0001); and area under the curve on Q-DSA increased by 1058.58 ± 199.08 (P = .0043). Synovial inflammation, hypervascularization, and osteophyte formations were present in all osteoarthritis knees. Histology scores showed strong correlation with CE-MR imaging findings (Spearman correlation coefficient [SCC] = 0.742; P = .0002) and Q-DSA findings (SCC = 0.763; P < .0001) and weak correlation with DCE-MR imaging (SCC = -0.345; P = .329). Moderate correlation was found between CE-MR imaging and DSA findings (SCC = 0.536; P = .0004). CONCLUSIONS: In this early-stage knee osteoarthritis dog model, synovial inflammation and hypervascularization were found on imaging and confirmed by histology.

Neuroendocrine carcinoma arising in a tailgut cyst.

INTRODUCTION: A tailgut cyst, also called retrorectal cystic hamartoma, is a rare congenital lesion that forms most commonly in the retrorectal space. It is presumed to arise from remnants of early embryogenesis. PRESENTATION OF CASE: The following report describes a unique case of a retrorectal cystic hamartoma in a 53 year-old French Canadian man with a history of low back pain. The tumour underwent malignant transformation into a well-differentiated neuroendocrine carcinoma three years after the beginning of symptoms. DISCUSSION: This condition can be found at any age, but occurs especially among middle-aged women. Not only is it frequently misdiagnosed, but also several complications associated to the cyst have been reported such as infection and malignant transformation. This is why complete surgical excision of the tailgut cyst is currently recommended.

Uterine lipoleiomyosarcoma: Complete medullary compression as presentation of a solitary metastasis.

•A rare case of lipoleiomyosarcoma.•Patient presented at our center with paraplegia caused by a solitary vertebral metastasis of a uterine cancer.•Lobectomy performed for a solitary lung metastasis.

Cutaneous Apocrine Carcinoma With an In Situ Component and Histiocytoid and Signet-Ring Cells.

We present a case of cutaneous apocrine carcinoma arising in the axilla of a 71-year-old man. The tumor had a significant component of histiocytoid and signet-ring cells as well as in situ carcinoma within the apocrine glands. The cells expressed GATA3, gross cystic disease fluid protein 15, androgen receptor, and E-cadherin. Estrogen receptor, progesterone receptor, and human epidermal growth factor receptor 2 were negative. Clinical correlation was required to rule out a metastasis from the breast or the gastrointestinal tract. Although most cutaneous apocrine carcinomas do not behave aggressively, our patient developed bone metastases and eventually died of his disease. It is debated whether histiocytoid and signet-ring cell cutaneous carcinomas should be classified as apocrine neoplasm. The presence of in situ carcinoma associated with this kind of tumor has been reported only once in the literature. This characteristic and the immunohistochemical profile are in favor of apocrine differentiation.

Plasmodium infections and fluctuating asymmetry among children and teenagers from Senegal.

Although fluctuating asymmetry is a sensitive indicator of stress, its links with health remains controversial, especially in humans. Here, we explored for the first time the association between fluctuating asymmetry and malaria infections in humans, from 107 participants involved in a long term medical survey in Senegal. No clear relationship was detected. Depending on traits considered, associations were not significant, or (marginally) significant but not in the same directions. We discuss the possible reasons for the global weakness of the signals detected in this study.

Who is the puppet master? Replication of a parasitic wasp-associated virus correlates with host behaviour manipulation.

Many parasites modify their host behaviour to improve their own transmission and survival, but the proximate mechanisms remain poorly understood. An original model consists of the parasitoid Dinocampus coccinellae and its coccinellid host, Coleomegilla maculata; during the behaviour manipulation, the parasitoid is not in contact with its host anymore. We report herein the discovery and characterization of a new RNA virus of the parasitoid (D. coccinellae paralysis virus, DcPV). Using a combination of RT-qPCR and transmission electron microscopy, we demonstrate that DcPV is stored in the oviduct of parasitoid females, replicates in parasitoid larvae and is transmitted to the host during larval development. Next, DcPV replication in the host's nervous tissue induces a severe neuropathy and antiviral immune response that correlate with the paralytic symptoms characterizing the behaviour manipulation. Remarkably, virus clearance correlates with recovery of normal coccinellid behaviour. These results provide evidence that changes in ladybeetle behaviour most likely result from DcPV replication in the cerebral ganglia rather than by manipulation by the parasitoid. This offers stimulating prospects for research on parasitic manipulation by suggesting for the first time that behaviour manipulation could be symbiont-mediated.

Bodyguard manipulation in a multipredator context: different processes, same effect.

Parasites have evolved various strategies to exploit hosts to their own advantage. Bodyguard manipulations consist of usurping the behaviour of the host to confer some protection to the parasite and/or its offspring. Dinocampus coccinellae Schrank is a solitary endoparasitoid of the spotted lady beetle Coleomegilla maculata lengi Timberlake. The parasitoid larva grows inside the host until mature, then egresses and spins a cocoon between the ladybird's legs. Unlike most parasitoids, D. coccinellae does not kill its host during development, but keeps the coccinellid partially paralysed on top of the cocoon, where it acts as a bodyguard against natural enemies. As recently shown, the presence of a living ladybird on the parasitoid cocoon provides efficient protection against a predator, lacewing larvae. In the present study, we used predators with different foraging behaviours--jumping spiders and crickets--to explore the relevance of the bodyguard strategy for D. coccinellae in a multipredator context. Although the manner of the protection differs among the different tested predators, the presence of the ladybird always enhances parasitoid survival, even when it first increases detection of the cocoon-ladybird complex, as is the case with jumping spiders. Furthermore, although a dead bodyguard is sufficient to passively defend parasitoid cocoons against crickets, it provides only partial protection against jumping spiders. Altogether, these results support the bodyguard hypothesis in a multipredator context, since the presence of a living coccinellid significantly reduces cocoon predation by predators having different prey specificities, morphologies, and hunting behaviours.

A multi-approach study to delineate interactions between carabid beetles and soybean aphids.

In recent years, the soybean aphid, Aphis glycines Matsumura, has become the most important exotic pest of soybean, Glycine max (L.) Merrill, in North America. Given the significant yield losses that are reported, considerable effort has been expended to characterize the natural enemy community associated with this pest. Several indigenous and naturalized predators have been identified as potential biological control agents, and these include carabid beetles, an abundant and important family of aphid predators. The objectives of this study were to assess the incidence of field predation by Pterostichus melanarius (Illiger), the most common carabid species in Québec soybeans, using molecular gut-content analysis, and to quantify its impact on A. glycines populations through laboratory and field cage experiments. Throughout the growing season between 16.8% (during low aphid density) and 33.7% (at times of high aphid density) of P. melanarius tested positive for aphid DNA. Furthermore, although laboratory feeding trials confirmed that P. melanarius prey on A. glycines, short-term field cage experiments failed to demonstrate a significant reduction of A. glycines populations by carabid beetles. These results suggest a relatively weak interaction between P. melanarius and A. glycines when pest densities are high, but the high predation rate when aphid densities are particularly low suggests these natural enemies may function as important early-season predators.

Malignant perineurioma (malignant peripheral nerve sheath tumor with perineural differentiation).

The great majority of malignant peripheral nerve sheath tumors (MPNST) exhibit Schwannian differentiation. In recent years, a subset of perineurial MPNST (malignant perineurioma) has been identified based on their histologic, immunohistochemical and ultrastructural features. Immunopositivity for epithelial membrane antigen (EMA), glut-1 and claudin-1, is characteristic. Such tumors must be distinguished from benign perineurioma and a variety of atypical or malignant soft tissue tumors featuring EMA positivity. Herein, we report a perineurial MPNST involving the buttock of a 42-year-old woman. Nerve involvement was noted. The clinicopathologic features of reported examples are ummarized and key differential diagnoses are discussed.

The cost of a bodyguard.

Host manipulation by parasites not only captures the imagination but has important epidemiological implications. The conventional view is that parasites face a trade-off between the benefits of host manipulation and their costs to fitness-related traits, such as longevity and fecundity. However, this trade-off hypothesis remains to be tested. Dinocampus coccinellae is a common parasitic wasp of the spotted lady beetle Coleomegilla maculata. Females deposit a single egg in the haemocoel of the host, and during larval development the parasitoid feeds on host tissues. At the prepupal stage, the parasitoid egresses from its host by forcing its way through the coccinellid's abdominal segments and begins spinning a cocoon between the ladybird's legs. Remarkably, D. coccinellae does not kill its host during its development, an atypical feature for parasitoids. We first showed under laboratory conditions that parasitoid cocoons that were attended by a living and manipulated ladybird suffered less predation than did cocoons alone or cocoons under dead ladybirds. We then demonstrated that the length of the manipulation period is negatively correlated with parasitoid fecundity but not with longevity. In addition to documenting an original case of bodyguard manipulation, our study provides the first evidence of a cost required for manipulating host behaviour.

Endothelin-1 (ET-1) promotes MMP-2 and MMP-9 induction involving the transcription factor NF-kappaB in human osteosarcoma.

In the present study, we have investigated the effect of (i) ET-1 (endothelin-1) and its precursor, big ET-1, on MMP (matrix metalloproteinase)-2 and MMP-9 synthesis and activity in osteosarcoma tissue, and (ii) ET-1 receptor antagonists on cell invasion. Using Western blotting, zymography, RT-PCR (reverse transcription-PCR), immunohistochemistry, immunofluorescence and Northern blotting, we have shown that ET-1 and ET-1 receptors (ET(A) and ET(B)) were expressed in these cells. Additionally, we have demonstrated that ET-1 markedly induced the synthesis and activity of MMP-2, which was significantly increased when compared with MMP-9. Furthermore, inhibition of NF-kappaB (nuclear factor kappaB) activation blocked MMP-2 production and activity, indicating the involvement of NF-kappaB, a ubiquitous transcription factor playing a central role in the differentiation, proliferation and malignant transformation. Since ET-1 acts as an autocrine mediator through gelatinase induction and because inhibition of ET(A) receptor is beneficial for reducing both basal and ET-1-induced osteosarcoma cell invasion, targeting this receptor could be an attractive therapeutic alternative for the successful treatment of osteosarcoma.

The effect of development time on the fitness of female Trichogramma evanescens.

Trichogramma are facultative gregarious egg parasitoids that attack a wide range of lepidopterous eggs. Because hosts in which parasitoids develop vary in terms of available food, the progeny produced by parasitoid females vary in size and fitness. While one might expect that the developmental rate and emergence rhythm should be similar for all individuals reared under the same environmental conditions, variations in the duration of development of individuals reared under uniform conditions have been found in several insect species. In the Hymenopteran egg parasitoid Trichogramma evanescens Westwood (Hymenoptera: Trichogrammatidae) adults emerge at the beginning of the photoperiod on two consecutive days. Longer development may influence the fitness of adults and have an impact on mating opportunities. Size, longevity and daily and lifetime fecundity were measured for female T. evanescens that developed in nine and ten days. We observed a significant relationship between size and both longevity and lifetime fecundity. While early emerging females did not live longer and did not produce progeny with a different sex-ratio than females that emerged later, they were larger and produced more progeny than late females. We conclude that early emerging females have a higher fitness than late emerging females T. evanescens.