401 research outputs found
Inversion of hematocrit partition at microfluidic bifurcations
Partitioning of red blood cells (RBCs) at the level of bifurcations in the
microcirculatory system affects many physiological functions yet it remains
poorly understood. We address this problem by using T-shaped microfluidic
bifurcations as a model. Our computer simulations and in vitro experiments
reveal that the hematocrit () partition depends strongly on RBC
deformability, as long as % (within the normal range in
microcirculation), and can even lead to complete deprivation of RBCs in a child
branch. Furthermore, we discover a deviation from the Zweifach-Fung effect
which states that the child branch with lower flow rate recruits less RBCs than
the higher flow rate child branch. At small enough , we get the inverse
scenario, and the hematocrit in the lower flow rate child branch is even higher
than in the parent vessel. We explain this result by an intricate up-stream RBC
organization and we highlight the extreme dependence of RBC transport on
geometrical and cell mechanical properties. These parameters can lead to
unexpected behaviors with consequences on the microcirculatory function and
oxygen delivery in healthy and pathological conditions.Comment: 16 page
Probing superfluidity in a quasi two-dimensional Bose gas through its local dynamics
We report direct evidence of superfluidity in a quasi two-dimensional Bose
gas by observing its dynamical response to a collective excitation. Relying on
a novel local correlation analysis, we are able to probe inhomogeneous clouds
and reveal their local dynamics. We identify in this way the superfluid and
thermal phases inside the gas and locate the boundary at which the
Berezinskii--Kosterlitz--Thouless crossover occurs. This new analysis also
allows to evidence the coupling of the two fluids which induces at finite
temperatures damping rates larger than the usual Landau damping
Non-inertial lateral migration of vesicles in bounded Poiseuille flow
Cross-streamline non-inertial migration of a vesicle in a bounded Poiseuille
flow is investigated experimentally and numerically. The combined effects of
the walls and of the curvature of the velocity profile induce a movement
towards the center of the channel. A migration law (as a function of relevant
structural and flow parameters) is proposed that is consistent with
experimental and numerical results. This similarity law markedly differs from
its analogue in unbounded geometry. The dependency on the reduced volume
and viscosity ratio is also discussed. In particular, the migration
velocity becomes non monotonous as a function of beyond a certain
.Comment: 5 pages, 3 figures. To appear in Phys. Fluid
Draft Genome Sequence of Photorhabdus luminescens Strain BA1, an Entomopathogenic Bacterium Isolated from Nematodes Found in Egypt
Photorhabdus luminescens strain BA1 is an entomopathogenic bacterium that forms a symbiotic association with Heterorhabditis nematodes. We report here a 5.0-Mbp draft genome sequence for P. luminscens strain BA1, with a G+C content of 42.46% and 4,250 candidate protein-coding genes
Draft Genome Sequence of Photorhabdus temperata Strain Meg1, an Entomopathogenic Bacterium Isolated from Heterorhabditis megidis Nematodes
Photorhabdus temperata strain Meg1 is an entomopathogenic bacterium that forms a symbiotic association with Heterorhabditis nematodes. We report here a 4.9-Mbp draft genome sequence for P. temperata strain Meg1, with a G+C content of 43.18% and containing 4,340 candidate protein-coding genes
Schistosomiasis and Urinary Bladder Cancer in North Western Tanzania: A Retrospective Review of 185 Patients.
Worldwide, cancers of the urinary bladder are well known to be associated with environmental chemical carcinogens such as smoking and occupational exposure to polycyclic aromatic hydrocarbons. These cancers are typically transitional cell carcinoma (urothelial carcinoma). In areas where schistosomiasis is endemic there is a high incidence of squamous cell carcinoma of the urinary bladder. Schistosomiasis causes chronic granulomatous cystitis leading to squamous metaplasia of transitional epithelium, and subsequently development of squamous cell carcinoma. The western part of Tanzania on the shores of Lake Victoria is such an endemic area. This study was done to document the burden of urinary bladder cancer associated with schistosomiasis in this region. This was a descriptive retrospective study of histologically confirmed cases of urinary bladder cancer seen at the Department of Pathology Bugando Medical Centre (BMC) over a period of 10 years. Data were retrieved from the records of the Departments of Pathology, Medical Records and Surgery. Data were analyzed by the use of contingency tables. A total of 185 patients were diagnosed with cancer of the urinary bladder during the study period, where as 90 (48.6%) were males and 95 (51.4) were females. The mean age at diagnosis was 54.3 years. Squamous cell carcinoma was the most frequent histological type (55.1%), followed by conventional transitional cell carcinoma (40.5%). Eighty three of all cancer cases (44.9%) were found to have schistosomal eggs. Schistosomiasis was commonly associated with squamous cancers compared to non squamous cancers. Most of the cancers associated with schistosomiasis had invaded the muscularis propria of the urinary bladder at the time of diagnosis (p<0.001) and such cancers were frequent below 50 years of age with a significant statistical difference (p<0.001). Poorly differentiated tumors were more frequent in females than males with a significant statistical difference (p=0.006). The majority of urinary bladder cancers seen in the Lake Region were squamous cell carcinoma associated with schistosomiasis. These cancers showed an aggressive behavior and were commonly seen in the younger age groups. Effective control of schistosomiasis in this region should significantly reduce the burden of urinary bladder cancer
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Systemically administered AAV9-sTRAIL combats invasive glioblastoma in a patient-derived orthotopic xenograft model
Adeno-associated virus (AAV) vectors expressing tumoricidal genes injected directly into brain tumors have shown some promise, however, invasive tumor cells are relatively unaffected. Systemic injection of AAV9 vectors provides widespread delivery to the brain and potentially the tumor/microenvironment. Here we assessed AAV9 for potential glioblastoma therapy using two different promoters driving the expression of the secreted anti-cancer agent sTRAIL as a transgene model; the ubiquitously active chicken β-actin (CBA) promoter and the neuron-specific enolase (NSE) promoter to restrict expression in brain. Intravenous injection of AAV9 vectors encoding a bioluminescent reporter showed similar distribution patterns, although the NSE promoter yielded 100-fold lower expression in the abdomen (liver), with the brain-to-liver expression ratio remaining the same. The main cell types targeted by the CBA promoter were astrocytes, neurons and endothelial cells, while expression by NSE promoter mostly occurred in neurons. Intravenous administration of either AAV9-CBA-sTRAIL or AAV9-NSE-sTRAIL vectors to mice bearing intracranial patient-derived glioblastoma xenografts led to a slower tumor growth and significantly increased survival, with the CBA promoter having higher efficacy. To our knowledge, this is the first report showing the potential of systemic injection of AAV9 vector encoding a therapeutic gene for the treatment of brain tumors
Benchopt: Reproducible, efficient and collaborative optimization benchmarks
Numerical validation is at the core of machine learning research as it allows
to assess the actual impact of new methods, and to confirm the agreement
between theory and practice. Yet, the rapid development of the field poses
several challenges: researchers are confronted with a profusion of methods to
compare, limited transparency and consensus on best practices, as well as
tedious re-implementation work. As a result, validation is often very partial,
which can lead to wrong conclusions that slow down the progress of research. We
propose Benchopt, a collaborative framework to automate, reproduce and publish
optimization benchmarks in machine learning across programming languages and
hardware architectures. Benchopt simplifies benchmarking for the community by
providing an off-the-shelf tool for running, sharing and extending experiments.
To demonstrate its broad usability, we showcase benchmarks on three standard
learning tasks: -regularized logistic regression, Lasso, and ResNet18
training for image classification. These benchmarks highlight key practical
findings that give a more nuanced view of the state-of-the-art for these
problems, showing that for practical evaluation, the devil is in the details.
We hope that Benchopt will foster collaborative work in the community hence
improving the reproducibility of research findings.Comment: Accepted in proceedings of NeurIPS 22; Benchopt library documentation
is available at https://benchopt.github.io
The decision-making process for breast reconstruction after cancer surgery: representations of heterosexual couples in longstanding relationships
International audienceOBJECTIVES: Most people deal with intrusive life events such as cancer and the care trajectory together with their intimate partners. To our knowledge, no research has studied the involvement of the partner in the decision-making process regarding breast reconstruction (BR) after cancer. This study aimed to gain a better understanding of the couples' decision-making process for BR in the cancer context and particularly to investigate the partners' involvement in this process.METHOD: Eighteen participants (nine women who underwent a mastectomy following a first breast cancer and their intimate partners) took part in this study. We conducted semidirective interviews, and a general inductive approach was chosen to capture the representations of the couples.RESULTS: The women in the sample were aged between 33 and 66 years (M = 54, SD = 7.5) and their partner between 40 and 76 years (M = 59, SD = 11.6). The duration of their intimate relationship was on average 18 years (SD = 10.4; minimum = 4; maximum = 33). The analysis revealed 11 major themes. The two most salient ones were 'external influence' and 'implication of the partner'. The exploration of the subthemes revealed that the decision-making process is often reported as an interrelated experience by the couples and as a dyadic stressor. The partner's role is depicted as consultative and mostly supportive.CONCLUSION: These results provide new insights on the involvement of the partner in decision-making. Thus, it now seems crucial to develop a prospective study, which will help understand the progression of the decision-making process over time. Statement of contribution What is already known on this subject? Most people deal with intrusive life events such as cancer and the care trajectory together with their intimate partners. Shared decision-making between patients and physicians is now the 'gold standard' in Western Europe and the United States. However, in the context of breast reconstruction (BR) after cancer, factors guiding the decision-making process for BR, especially the potential involvement of the partner, are not very well understood. What does this study add? Provides a qualitative insight on the specific nature of heterosexual couples' representations regarding the decision-making process for breast reconstruction after cancer. Reveals that the decision-making process is often reported as an interrelated experience by the couples and as a dyadic stressor. Underlines the consultative function of partners with women engaged in breast reconstruction
Do's and Don'ts in Primary Aneurysmal Bone Cysts of the Proximal Femur in Children and Adolescents : Retrospective Multicenter EPOS Study of 79 Patients
Background:Aneurysmal bone cysts (ABC) are rare benign cystic bone tumors, generally diagnosed in children and adolescents. Proximal femoral ABCs may require specific treatment strategies because of an increased pathologic fracture risk. As few reports are published on ABCs, specifically for this localization, consensus regarding optimal treatment is lacking. We present a large retrospective study on the treatment of pediatric proximal femoral ABCs. Methods:All eligible pediatric patients with proximal femoral ABC were included, from 11 tertiary referral centers for musculo-skeletal oncology (2000-2021). Patient demographics, diagnostics, treatments, and complications were evaluated. Index procedures were categorized as percutaneous/open procedures and osteosynthesis alone. Primary outcomes were: time until full weight-bearing and failure-free survival. Failure was defined as open procedure after primary surgery, >3 percutaneous procedures, recurrence, and/or fracture. Risk factors for failure were evaluated. Results:Seventy-nine patients with ABC were included [mean age, 10.2 (+/- SD4.0) y, n=56 male]. The median follow-up was 5.1 years (interquartile ranges=2.5 to 8.8).Index procedure was percutaneous procedure (n=22), open procedure (n=35), or osteosynthesis alone (n=22). The median time until full weight-bearing was 13 weeks [95% confidence interval (CI)=7.9-18.1] for open procedures, 9 weeks (95% CI=1.4-16.6) for percutaneous, and 6 weeks (95% CI=4.3-7.7) for osteosynthesis alone (P=0.1). Failure rates were 41%, 43%, and 36%, respectively. Overall, 2 and 5-year failure-free survival was 69.6% (95% CI=59.2-80.0) and 54.5% (95% CI=41.6-67.4), respectively. Risk factors associated with failure were age younger than 10 years [hazard ratios (HR)=2.9, 95% CI=1.4-5.8], cyst volume >55 cm(3) (HR=1.7, 95% CI=0.8-2.5), and fracture at diagnosis (HR=1.4, 95% CI=0.7-3.3). Conclusions:As both open and percutaneous procedures along with osteosynthesis alone seem viable treatment options in this weight-bearing location, optimal treatment for proximal femoral ABCs remains unclear. The aim of the treatment was to achieve local cyst control while minimizing complications and ensuring that children can continue their normal activities as soon as possible. A personalized balance should be maintained between undertreatment, with potentially higher risks of pathologic fractures, prolonged periods of partial weight-bearing, or recurrences, versus overtreatment with large surgical procedures, and associated risks.Peer reviewe
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