•An original dissipative constitutive law of the finger soft tissues was proposed in the spectral domain.•The law parameters were identified on in vivo measurements of the static and dynamic ...stiffnesses.•A measurement campaign was conducted on a group of 20 subjects.•The model accuracy is 5% for the static case and 8% for the dynamic.•High dynamic pressure and dissipated power are localized near to the vibrating probe contact zone.
This study lays the groundwork for a multi-scale strategy that will lead to a better understanding and prediction of the effects of vibration on the digital arterial network. This is accomplished by modelling the mechanical and biological factors that could disturb the basal vasoconstriction balance in the fingertip. The first stage of this novel approach involved building and validating an original dissipative constitutive law for the fingertip soft tissue for the purpose of finite element modelling of the mechanical response of preloaded phalanges in vibration. This visco-hyperelastic constitutive law was established by means of a two-stage procedure for combining a classical pure static nonlinear law with an original dissipative model. First, the parameters of an Ogden–Hill pure static nonlinear constitutive law were identified using a constrained optimisation algorithm. Second, an original viscous dissipation model was proposed in the spectral domain. This model is based on the linearization of the nonlinear quasi-linear viscoelasticity law and the use of a viscoelastic relaxation modulus, expressed as a continuous distribution of relaxation spectra suitable for living tissues. The experimental data used to fit this model were the static and dynamic stiffnesses of preloaded fingertips acquired from a group of 20 subjects. The relative errors between the measured and simulated stiffnesses were less than 5% in the static procedure and approximately 8% using dynamic analysis. The computed mechanical pressure and maximal tangential stress within the fingertip were high in the soft tissues close to the vibration excitation and also in the bones and interphalangeal cartilages far from the vibration source. Mechanical power was only dissipated significantly in the immediate vicinity of the contact area between the probe and the finger. The main contribution of this study was to implement and identify the parameters of a new spectral dissipative law for fingertip soft tissues. This work may apply in occupational health for modifying the vibration dose assessment or for the follow-up and screening of connective tissue diseases.
Sustained exposure to high-level hand-transmitted vibrations may result in angioneurotic disorders, which partly originate from vibration-altered hemodynamics in the finger arteries when repeating ...these disturbances throughout working life. Hence, the aim of this study is to assess the most relevant hemodynamic descriptors in the digital arteries, determine the relationship between the latter and vibration features, and gain better understanding of the physiological mechanisms involved.
An experimental setup, mainly comprised of an ultra-high frequency ultrasound scanner and a vibration shaker, was used to image the digital proper volar arteries of the forefinger. Raw ultrasound data were post-processed by custom-made numerical routines to supply a pulsatile fluid mechanics model for computing the hemodynamic descriptors. Twenty-four healthy volunteers participated in the measurement campaign. Classical statistical methods were then applied to the dataset and also the wavelet transform for calculating the signal power in the frequency bands matching cardiac, respiratory, myogenic and neurogenic activities.
The artery diameter, the wall shear stress - WSS - and the WSS temporal gradient - WSSTG - were found to be the most relevant descriptors. Vibration-induced WSS was divided by three compared to its basal value whatever the vibration frequency and it was proportional to log
of the acceleration level. Marked increases in WSSTG when stopping vibration might also lead to adverse health effects. Vibration caused a drop in WSS power for the frequency band associated with the neurogenic activity of the sympathetic nervous system.
This study may pave the way for a new framework to prevent vibration-induced vascular risk.
An experimental vibration test bench was built for measuring the dynamic stiffnesses and dissipated power densities of preloaded distal phalanges undergoing vibration. The aim of this test bench was ...to analyse the effects of vibration frequency, static preloading, and vibration excitation amplitude on local biodynamic response. Prior to implementation, the test bench was validated by comparison with a tension–compression testing machine and a reference dynamic mechanical analyser. A measurement study was then conducted on a group of 20 subjects. The mean dynamic stiffness showed that the mechanical behaviour of the index finger distal phalanx is similar to that of a complex amorphous polymer: it exhibits frequency-related stiffening with a rubbery plateau, a glassy transition zone, and a glassy state. The static preloading condition considerably modifies the dynamic response of the phalanx, as well as the dissipated power, which is significantly greater when the preloading is high. An amplitude-related softening phenomenon, similar to the Payne effect for rubber, was also revealed. This can be explained by the thixotropic character of the extracellular matrix of the distal phalanx soft tissues.
Extensive exposure of the hand–arm system to regular vibration may lead to various disorders and injuries, due in part to changes in mechanical quantities, such as dynamic stress, strain, or dissipated power density, arising from the propagation of such vibration. Nowadays, the direct measurement of this biodynamic response inside soft tissues is still extremely challenging. A way to assess the overall mechanical effects of these local quantities on the human finger is to measure and analyse both the macroscopic stiffness and the dissipated power of fingers.
•A system to measure the dynamic stiffness of preloaded vibrated phalanxes was built.•A measurement campaign was conducted on a group of 20 subjects.•The mechanical behavior is similar to that of a complex amorphous polymer.•The stiffness shows a rubbery plateau, a glassy transition zone and a glassy state.•An amplitude-related softening phenomenon similar to the Payne effect was revealed.
Blastocystis sp. is a common intestinal parasite infecting humans and a wide range of animals worldwide. It exhibits an extensive genetic diversity and 17 subtypes (STs) have thus far been identified ...in mammalian and avian hosts. Since several STs are common to humans and animals, it was proposed that a proportion of human infections may result from zoonotic transmission. However, the contribution of each animal source to human infection remains to be clarified. Therefore, the aim of this study was to expand our knowledge of the epidemiology and host specificity of this parasite by performing the largest epidemiological survey ever conducted in animal groups in terms of numbers of species screened. A total of 307 stool samples from 161 mammalian and non-mammalian species in two French zoos were screened by real-time PCR for the presence of Blastocystis sp. Overall, 32.2% of the animal samples and 37.9% of the species tested were shown to be infected with the parasite. A total of 111 animal Blastocystis sp. isolates were subtyped, and 11 of the 17 mammalian and avian STs as well as additional STs previously identified in reptiles and insects were found with a varying prevalence according to animal groups. These data were combined with those obtained from previous surveys to evaluate the potential risk of zoonotic transmission of Blastocystis sp. through the comparison of ST distribution between human and animal hosts. This suggests that non-human primates, artiodactyls and birds may serve as reservoirs for human infection, especially in animal handlers. In contrast, other mammals such as carnivores, and non-mammalian groups including reptiles and insects, do not seem to represent significant sources of Blastocystis sp. infection in humans. In further studies, more intensive sampling and screening of potential new animal hosts will reinforce these statements and expand our understanding of the circulation of Blastocystis sp. in animal and human populations.
p53-mutated endometrial carcinomas tend to recur and develop distant metastases. Therefore, the detection of new potential therapeutic targets such as HER2 is particularly interesting. In this ...retrospective study, which considered over 118 endometrial carcinomas, the p53 mutation was detected in 29.6% of cases. In these cases, the HER2 protein profile was studied via immunohistochemistry, and an overexpression of HER2 protein (++ or +++) was noted in 31.4%. The CISH technique was used in these cases to determine if gene amplification was present. In 18% of cases, the technique was not conclusive. Amplification of the HER2 gene was observed in 36.3% of cases and 36.3% of cases showed a polysomal-like aneusomy for centromere 17. Amplification was found in serous carcinomas, clear cell carcinomas and carcinosarcomas, highlighting the future potentiality of HER2-targeted therapies in these variants of aggressive carcinomas.
Cancer progression results from a complex interplay between tumor cells and the extracellular milieu. In breast carcinoma, the stromal microenvironment has been suggested to play a major role in ...promoting tumor growth, progression, and invasion. The stroma of 154 resected specimens of invasive breast carcinoma of no special type was quantified using a digital image analyzer. Statistical analyses were performed between the quantity of stroma and survival, as well as between progression-free survival and clinicopathological data. Levels of myofibroblastic stroma varied from 0-46%, with a median of 15.1% and a standard deviation of 7.5. The myofibroblastic stromal reaction was statistically greater in grade 2 and 3 tumors (p = 0.029). Furthermore, there was a trend for worse progression-free survival in the group of node-negative tumors with strong smooth-muscle actin stromal expression (Log rank = 0.075). The present study demonstrates that the myofibroblastic reaction of breast invasive carcinoma of no special type is not merely a passive reaction, but seems to be an integral part of the neoplastic process by facilitating tumor progression and invasion. Additional, larger studies on mechanisms of stromal change are needed and may potentially lead to novel treatments.
Trichomonas vaginalis is the most common non-viral human sexually transmitted pathogen and importantly, contributes to facilitating the spread of HIV. Yet very little is known about its surface and ...secreted proteins mediating interactions with, and permitting the invasion and colonisation of, the host mucosa. Initial annotations of T. vaginalis genome identified a plethora of candidate extracellular proteins.
Data mining of the T. vaginalis genome identified 911 BspA-like entries (TvBspA) sharing TpLRR-like leucine-rich repeats, which represent the largest gene family encoding potential extracellular proteins for the pathogen. A broad range of microorganisms encoding BspA-like proteins was identified and these are mainly known to live on mucosal surfaces, among these T. vaginalis is endowed with the largest gene family. Over 190 TvBspA proteins with inferred transmembrane domains were characterised by a considerable structural diversity between their TpLRR and other types of repetitive sequences and two subfamilies possessed distinct classic sorting signal motifs for endocytosis. One TvBspA subfamily also shared a glycine-rich protein domain with proteins from Clostridium difficile pathogenic strains and C. difficile phages. Consistent with the hypothesis that TvBspA protein structural diversity implies diverse roles, we demonstrated for several TvBspA genes differential expression at the transcript level in different growth conditions. Identified variants of repetitive segments between several TvBspA paralogues and orthologues from two clinical isolates were also consistent with TpLRR and other repetitive sequences to be functionally important. For one TvBspA protein cell surface expression and antibody responses by both female and male T. vaginalis infected patients were also demonstrated.
The biased mucosal habitat for microbial species encoding BspA-like proteins, the characterisation of a vast structural diversity for the TvBspA proteins, differential expression of a subset of TvBspA genes and the cellular localisation and immunological data for one TvBspA; all point to the importance of the TvBspA proteins to various aspects of T. vaginalis pathobiology at the host-pathogen interface.
Malignant eccrine spiradenoma is one of the rarest sweat-gland tumors. Here, we describe a rare case of low grade malignant eccrine spiradenoma located at the vulva.
The vulvar lesion was described ...as a mass measured 3.5 cm and located in the dermis and subcutis with no attachment to the epidermis. The neoplasm was arranged in ragged sheets or solid nodules sometimes with focal necrosis. The tumor cells had hyperchromatism, pleomorphism, and prominent nucleoli with high mitotic index and KI-67 estimated at 70-80%.
It's only the fifth case of malignant eccrine spiradenoma localized at the vulva. This is the first time that an HPV genotyping was made in this type of lesion with no HPV found while the p16 expression was diffuse. Moreover, it's the first time that a p53 mutation is detected by sequencing in this location.
Patients with breast cancer undergoing systemic therapies can have mixed response to treatment, with some lesions reducing their dimensions or also, in some cases, disappearing, and others ...progressing. Of note, breast cancer is an example of tumor heterogeneity, and this reflects the ability of the tumor to adapt to changing conditions and to overcome constraints to growth and dissemination. Hence, a mixed response to treatment may indicate that some clones have become resistant to the treatment and are triggering a disease progression. Nevertheless, a differential diagnosis should always be implemented when new lesions are detected, to rule out potential different etiologies. Too often subjects who received a prior diagnosis of cancer may face stigma of “cancer patients” although they have been successfully cured and have no evidence of residual disease. The systematic implementation of a sensible, appropriate differential diagnosis can help reduce the time to diagnosis and to treatment, with positive impact in patients’ outcomes and quality of life. Our case report describes the incidental finding of lung lesions in a woman treated for early breast cancer and highlights the importance of differential diagnosis in the specific subset of subjects who received a prior diagnosis of cancer.
A ductal adenoma is a rare benign epithelial tumour of the breast. Its origin is unclear, but some authors consider that they arise from intraductal papilloma that undergoes sclerosis and lose their ...papillary architecture.
A 43-year-old woman presented a palpable mass in the right breast. Mammography revealed a well-demarcated nodule of 9 mm. Histological examination showed a nodular proliferation of glands without papillary structures circumscribed by a dense fibrous wall. Glandular tubules were round or ovoid. The epithelial cells showed no atypia and mitosis were absent. Gene mutation testing has been performed.
To the best of our knowledge, we reported the first case of a ductal adenoma with AKT1 and EGFR mutations. We also reviewed the literature concerning the molecular profile of ductal adenoma and papillary lesions.
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