Schwannoma, a rare tumor of the seminal vesicle

We present a rare case of a schwannoma of the seminal vesicle that occurred in a 43-year-old male with symptoms of the lower urinary tract. Ultrasonography and magnetic resonance imaging documented a solid mass in the patient's left seminal vesicle. A transvesical approach with a transtrigonal midline incision was successfully performed. The microscopic aspect was compatible with schwannoma

Adenoid cystic carcinoma of the palpebral lobe of the lacrimal gland – case report and literature review

Epithelial tumors of the lacrimal gland are rare and usually develop in the orbital lobe. We report the exceedingly rare occurrence of a primary adenoid cystic carcinoma in the palpebral lobe of the lacrimal gland. A 26-year-old female was referred for evaluation of a gradually enlarging mass in the lateral upper eyelid, previously diagnosed as a chalazion. Computed tomography revealed a heterogeneous round lesion anterior to the orbital rim. Excisional biopsy was compatible with an adenoid cystic carcinoma. After excluding distant metastasis, and as the patient refused adjuvant radiotherapy, a second surgical procedure, with wide local excision, was indicated. Follow-up showed no recurrence. This case highlights the importance of performing a thorough clinical examination when diagnosing any lateral upper eyelid mass. A high index of suspicion for malignant tumors of the lacrimal gland should always be maintained, and a complete excision with histological analysis should be preferred whenever possible.info:eu-repo/semantics/publishedVersio

A new viscoelastic benchmark flow: Stationary bifurcation in a cross-slot

AbstractIn this work we propose the cross-slot geometry as a candidate for a numerical benchmark flow problem for viscoelastic fluids. Extensive data of quantified accuracy is provided, obtained via Richardson extrapolation to the limit of infinite refinement using results for three different mesh resolutions, for the upper-convected Maxwell, Oldroyd-B and the linear form of the simplified Phan-Thien–Tanner constitutive models. Furthermore, we consider two types of flow geometry having either sharp or rounded corners, the latter with a radius of curvature equal to 5% of the channel’s width. We show that for all models the inertialess steady symmetric flow may undergo a bifurcation to a steady asymmetric configuration, followed by a second transition to time-dependent flow, which is in qualitative agreement with previous experimental observations for low Reynolds number flows. The critical Deborah number for both transitions is quantified and a set of standard parameters is proposed for benchmarking purposes

Influence of channel aspect ratio on the onset of purely-elastic flow instabilities in three-dimensional planar cross-slots

In this work, we perform creeping-flow simulations of upper-convected Maxwell and simplified Phan-Thien-Tanner fluids to study the purely-elastic steady bifurcation and transition to time-dependent flow in three-dimensional planar cross-slots. By analysing the flow in geometries with aspect ratios ranging from the near Hele-Shaw flow like limit, up to the very deep, two-dimensional limit, we are able to characterize the mechanism of the cross-slot bifurcation with significant detail. We conclude that the bifurcation mechanism is similar to a buckling instability, by which fluid is redirected via paths of least resistance, resulting in the emergence of peripheral stagnation points, above and below the central stagnation point. The intake of matter at the centre via the inlet axis is thus reduced, being compensated by fluid flowing through low resistance corridors along the central vertical axis, above and below the central point. Furthermore, we propose and locally compute a modified Pakdel-McKinley criterion, thereby producing a scalar stability field and suggesting emergent peripheral stagnation points also indirectly contribute to the onset of time-dependent flow. (c) 2015 The Authors. Published by Elsevier B.V

An anaphase surveillance mechanism prevents micronuclei formation from frequent chromosome segregation errors

Micronuclei are a hallmark of cancer and several other human disorders. Recently, micronuclei were implicated in chromothripsis, a series of massive genomic rearrangements that may drive tumor evolution and progression. Here, we show that Aurora B kinase mediates a surveillance mechanism that integrates error correction during anaphase with spatial control of nuclear envelope reassembly to prevent micronuclei formation. Using high-resolution live-cell imaging of human cancer and non-cancer cells, we uncover that anaphase lagging chromosomes are more frequent than previously anticipated, yet they rarely form micronuclei. Micronuclei formation from anaphase lagging chromosomes is prevented by a midzone-based Aurora B phosphorylation gradient that stabilizes kinetochore-microtubule attachments and assists spindle forces required for anaphase error correction while delaying nuclear envelope reassembly on lagging chromosomes, independently of microtubule density. We propose that a midzone-based Aurora B phosphorylation gradient actively monitors and corrects frequent chromosome segregation errors to prevent micronuclei formation during human cell division.We thank António Pereira and Ana Almeida for assistance with CH-STED, Ariana Jacome for the generation of lentiviral vectors, Cristina Ferrás and Marco Novais-Cruz for drawing attention to the effects of nocodazole treatment and washout on the Aurora B phosphorylation gradient, current and former lab members for suggestions, and Jonathan Higgins and Andrew McAinsh for discussing results prior to publication. This work was funded by the European Research Council (ERC) consolidator grant CODECHECK , under the European Union’s Horizon 2020 research and innovation programme (grant agreement 681443 ), and Fundação para a Ciência e a Tecnologia of Portugal ( PTDC/MED-ONC/3479/2020 )

Functionalized Cyclopentenones with Low Electrophilic Character as Anticancer Agents

In this study were synthesized non-Michael acceptor cyclopentenones (CP) from biomass derivative furfural as anticancer agents. Cyclic enones, both from natural sources and synthetic analogues, have been described as cytotoxic agents. Most of these agents were unsuccessful in becoming valuable therapeutic agents due to toxicity problems derived from unselective critical biomacromolecule alkylation. This may be caused by Michael addition to the enone system. Ab initio studies revealed that 2,4-substituted CPs are less prone to Michael additions, and as such were tested three families of those derivatives. We prepare the new CPs from furfural through a tandem furan ring opening/nazarov electrocyclization and further functionalization. Experimentally the 2,4-substituted CPs exhibited no reactivity towards sulphur nucleophiles, while maintaining cytotoxicity against HT-29, MCF-7, NCI-H460, HCT-116 and MDA-MB 231 cells lines. Moreover, the selected CP are non-toxic against healthy HEK 293T cell lines and present proper calculated drug-like properties

Electroosmosis modulated peristaltic biorheological flow through an asymmetric microchannel : mathematical model

A theoretical study is presented of peristaltic hydrodynamics of an aqueous electrolytic nonNewtonian Jeffrey bio-rheological fluid through an asymmetric microchannel under an applied axial electric field. An analytical approach is adopted to obtain the closed form solution for velocity, volumetric flow, pressure difference and stream function. The analysis is also restricted under the low Reynolds number assumption and lubrication theory approximations. Debye-Hückel linearization (i.e. wall zeta potential ≤ 25mV) is also considered. Streamline plots are also presented for the different electro-osmotic parameter, varying magnitudes of the electric field (both aiding and opposing cases) and for different values of the ratio of relaxation to retardation time parameter. Comparisons are also included between the Newtonian and general non-Newtonian Jeffrey fluid cases. The results presented here may be of fundamental interest towards designing lab-on-a-chip devices for flow mixing, cell manipulation, micro-scale pumps etc. Trapping is shown to be more sensitive to an electric field (aiding, opposing and neutral) rather than the electro-osmotic parameter and viscoelastic relaxation to retardation ratio parameter. The results may also help towards the design of organ-on-a-chip like devices for better drug design

Toxoplasma seroprevalence in a rural population in France: detection of a household effect

<p>Abstract</p> <p>Background</p> <p><it>Toxoplasma gondii</it>, the agent of toxoplasmosis, has a complex life cycle. In humans, the parasite may be acquired either through ingestion of contaminated meat or through oocysts present in the environment. The importance of each source of contamination varies locally according to the environment characteristics and to differences concerning human eating habits and the presence of cats; thus, the risk factors may be determined through fine-scale studies. Here, we searched for factors associated with seropositivity in the population of two adjacent villages in Lorraine region, France.</p> <p>Methods</p> <p>All voluntary inhabitants filled out a questionnaire and gave a blood sample. The seroprevalence was estimated globally and according to the inhabitants' ages using a cubic spline regression. A mixed logistic regression model was used to quantify the effect of individual and household factors on the probability of seropositivity.</p> <p>Results</p> <p>Based on serological results from 273 persons, we estimated seroprevalence to be 47% (95% confidence interval: 41 to 53%). That seroprevalence increased with age: the slope was the steepest up to the age of 40 years (OR = 2.48 per 10-year increment, 95% credibility interval: [1.29 to 5.09]), but that increase was not significant afterwards. The probability of seropositivity tended to be higher in men than in women (OR = 2.01, 95% credibility interval: [0.92 to 4.72]) and in subjects eating raw vegetables at least once a week than in the others (OR = 8.4, 95% credibility interval: [0.93 to 72.1]). These effects were close to statistical significance. The multivariable analysis highlighted a significant seroprevalence heterogeneity among households. That seroprevalence varied between 6 and 91% (5^thand 95^thpercentile of the household seropositivity distribution).</p> <p>Conclusion</p> <p>The major finding is the household effect, with a strong heterogeneity of seroprevalence among households. This effect may be explained by common exposures of household members to local risk factors. Future work will quantify the link between the presence of oocysts in the soil and the seroprevalence of exposed households using a spatial analysis.</p