Drag and lift coefficients of ellipsoidal particles under rarefied flow conditions.

The capability to simulate a two-way coupled interaction between a rarefied gas and an arbitrary-shaped colloidal particle is important for many practical applications, such as aerospace engineering, lung drug delivery, and semiconductor manufacturing. By means of numerical simulations based on the direct-simulation Monte Carlo (DSMC) method, we investigate the influence of the orientation of the particle and rarefaction on the drag and lift coefficients, in the case of prolate and oblate ellipsoidal particles immersed in a uniform ambient flow. This is done by modeling the solid particles using a cut-cell algorithm embedded within our DSMC solver. In this approach, the surface of the particle is described by its analytical expression and the microscopic gas-solid interactions are computed exactly using a ray-tracing technique. The measured drag and lift coefficients are used to extend the correlations, based on the sine-squared drag law, available in the continuum regime to the rarefied regime, focusing on the transitional and free-molecular regimes. The functional forms of the correlations for the ellipsoidal particles are chosen as a generalization from the spherical case. We show that the fits over the data from numerical simulations can be extended to regimes outside the simulated range of Kn. Our approach allows to achieve a higher precision when compared with existing predictive models from the literature. Finally, we underline the importance of this work in providing correlations for nonspherical particles that can be used for point-particle Euler-Lagrangian simulations to address the problem of contamination from finite-size particles in high-tech mechanical systems.

Influence of numerical resolution on the dynamics of finite-size particles with the lattice Boltzmann method.

We investigate and compare the accuracy and efficiency of different numerical approaches to model the dynamics of finite-size particles using the lattice Boltzmann method (LBM). This includes the standard bounce-back (BB) and the equilibrium interpolation (EI) schemes. To accurately compare the different implementations, we first introduce a boundary condition to approximate the flow properties of an unbounded fluid in a finite simulation domain, taking into account the perturbation induced by a moving particle. We show that this boundary treatment is efficient in suppressing detrimental effects on the dynamics of spherical and ellipsoidal particles arising from the finite size of the simulation domain. We then investigate the performances of the BB and EI schemes in modeling the dynamics of a spherical particle settling under Stokes conditions, which can now be reproduced with great accuracy thanks to the treatment of the exterior boundary. We find that the EI scheme outperforms the BB scheme in providing a better accuracy scaling with respect to the resolution of the settling particle, while suppressing finite-size effects due to the particle discretization on the lattice grid. Additionally, in order to further increase the capability of the algorithm in modeling particles of sizes comparable to the lattice spacing, we propose an improvement to the EI scheme, the complete equilibrium interpolation (CEI). This approach allows us to accurately capture the boundaries of the particle also when located between two fluid nodes. We evaluate the CEI performance in solving the dynamics of an under-resolved particle under analogous Stokes conditions and also for the case of a rotating ellipsoid in a shear flow. Finally, we show that EI and CEI are able to recover the correct flow solutions also at small, but finite, Reynolds number. Adopting the CEI scheme it is not only possible to detect particles with zero lattice occupation, but also to increase up to one order of magnitude the accuracy of the dynamics of particles with a size comparable to the lattice spacing with respect to the BB and the EI schemes.

Correction to: Contribution of cryopreservation to the cumulative live birth rate: a large multicentric cycle-based data analysis from the Italian National Registry.

The original article unfortunately contained a mistake. The names of the collaborators were captured as authors of the article.

Contribution of cryopreservation to the cumulative live birth rate: a large multicentric cycle-based data analysis from the Italian National Registry.

PURPOSE: To estimate the contribution of cryopreservation to the cumulative live birth rate (CLBR) after law modification in Italy in the era of vitrification and freeze-all. METHODS: The Italian National Registry performed a cycle-based data collection. Nine Italian IVF clinics were involved incorporating a total of 10,260 fresh cycles performed between January 2015 and April 2016 resulting in 9273 oocyte retrievals and 3266 subsequent warming cycles from the same oocyte retrievals performed up to December 2016. Mean female age was 37 ± 4.3 years. Primary outcome measure was CLBR per oocyte retrieval. Confounding factors were tested in multivariate regression analysis, and the relative impact of cryopreservation to the CLBR in different patient categories was calculated. RESULTS: CLBR per oocyte retrieval was 32.6%, 26.5%, 18.7%, 13.0%, and 5.5% for women younger than 36, aged 36-39, 40-41, and older than 41 years, respectively. The total relative contribution of oocyte/embryo cryopreservation was 40.6% (95% CI 38.41-42.75). An association between maternal age, number of oocytes retrieved, fertilization rate, cryopreservation, and cumulative live birth was shown. When adjusted for confounders, a 2.3-fold increase was observed in the chance of live birth when cryopreservation was performed (OR 2.3; 95% CI 1.99-2.56). In high responder patients (> 15 oocytes retrieved) where freeze-all was applied in 67.6% of cycles to avoid the risk of hyper stimulation syndrome, the relative contribution of vitrification to the CLBR was 80.6%. CONCLUSIONS: Cryopreservation is essential in IVF and should always be available to patients to optimize success rates. Multicentric, cycle-based data analyses are crucial to provide infertile couples, clinicians, and regulatory bodies with accurate information on IVF effectiveness including fresh and cryopreserved cycles.

Patient-centered communication, patient satisfaction, and retention in care in assisted reproductive technology visits.

PURPOSE: To explore the association between patient-centered communication, patients' satisfaction, and retention in care in assisted reproductive technology (ART) visits. METHODS: ART visits at eight Italian clinics were videotaped and coded using the Roter Interaction Analysis System, which includes a Patient-Centered Index (PCI), a summary "patient-centered communication" ratio. After the visit, patients completed a satisfaction questionnaire (SATQ). After 3 months, patients were asked about their retention in care. Spearman correlations and Mann-Whitney tests were used to test associations between the study variables; the open-ended item of SATQ was analyzed through content analysis. RESULTS: Eighty-five visits were videotaped (involving 28 gynecologists and 160 patients). PCI score (µ = 0.51 ± 0.28) revealed a more disease-oriented communication during the visit. Patients reported high levels of satisfaction with the visit and identified in the information provision or in the doctor's humanity or kindness the main reasons of satisfaction. At the follow-up, the majority of the couples declared to have followed the clinicians' recommendations and to have remained related to the ART center. No associations were found among the study variables, except for a lower male satisfaction among couples who declared to have changed ART clinic. CONCLUSIONS: Contrary to what was expected, the style of physician-patient communication was not found to be associated with patient satisfaction and retention in care. However, patients were highly satisfied and engaged. The actual meaning of a communication that is "patient-centered" in the ART context might be wider, including the couples' need for information, as suggested by qualitative findings.

Doctor-couple communication during assisted reproductive technology visits.

STUDY QUESTION: What are the characteristics of doctor-couple communication content during actual ART visits? SUMMARY ANSWER: Physicians were mainly focused on providing biomedical information, while communication content from couples had a 2-fold focus on providing biomedical information and on positive talk. WHAT IS KNOWN ALREADY: Communication aspects in ART seem crucial for clinical decision-making, retention in care and critical conversations with couples due to low treatment success rates. However, no studies have been carried out on the actual interaction between the doctor and the couple in this context. STUDY DESIGN, SIZE, DURATION: This observational study involved 28 clinicians and 160 patients referred to eight Italian ART clinics during a one-year recruitment period. PARTICIPANTS/MATERIALS, SETTING, METHODS: ART visits at eight Italian clinics were videotaped. The visits were coded using the Roter Interaction Analysis System (RIAS), particularly focusing on RIAS composite categories, verbal dominance and patient-centeredness score. MAIN RESULTS AND THE ROLE OF CHANCE: A total of 85 visits were eligible for analysis (62% acceptance rate), involving 28 clinicians and 160 patients (including 75 couples). The average visit duration was 37 ± 17.7 min. The mean verbal dominance was 1.9 ± 0.86 (range: 0.72-5.74). Physicians mainly focused on providing biomedical information. Communication content from couples had a 2-fold focus on providing biomedical information and on positive talk. The mean of patient centeredness index (PCI) was 0.51 (SD = 0.28; range 0.08-1.77); visits in which the doctor was a woman or the treatment indication was for heterologous fertilization showed higher PCI scores. Overall, females accounted for 67% of all patient talk. Taking this imbalance into account as expected frequencies for each composite category, males reported significantly more utterances in almost all of the socioemotional categories. LIMITATIONS, REASONS FOR CAUTION: These results are preliminary and observational and only regard Italy. Communication during visits may have been biased since the professionals who agreed to participate showed an interest in communication issues. Another limitation is a possible Hawthorne effect due to the fact that participants were aware of being videotaped. WIDER IMPLICATIONS OF THE FINDINGS: Our study showed that ART physicians mainly adopted an informative model of communication and a more disease-oriented approach. Findings revealed the complexity of communication content during ART consultations, given its triadic characteristic in which the third party is also a patient; clinicians should be aware of this complex aspect and of the specific male and female perspectives to be taken into account. The results could be useful for training ART professionals. STUDY FUNDING/COMPETING INTEREST(S): This study was possible thanks to an unconditional grant from Ferring Spa to the Department of Health Sciences, University of Milan. There are no competing interests to declare. TRIAL REGISTRATION NUMBER: N/A.

PI3K regulation of the SKP-2/p27 axis through mTORC2.

The cyclin-dependent kinase inhibitor p27 is a key regulator of cell-cycle progression. Its expression and localization are altered in several types of malignancies, which has prognostic significance in cancers such as renal cell carcinoma (RCC). S-phase kinase-associated protein 2 (SKP-2) is an F-box protein that is part of the SKP-1/Cul1/F-box ubiquitin ligase complex that targets nuclear p27 among many other cell-cycle proteins for proteosomal degradation. Its overexpression has been observed in several tumor types. Signaling by phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT) has previously been shown to regulate the SKP-2/p27 axis. Recent evidence suggests that PI3K signaling may activate mammalian target of rapamycin complex 2 (mTORC2) activity. As PI3K signaling is known to regulate SKP-2 and p27, we sought to determine whether these effects were mediated by mTORC2. Here we provide additional genetic evidence that PI3K signaling activates mTORC2 kinase activity. We also demonstrate a novel role for mTORC2 in the modulation of nuclear p27 levels. In particular, mTORC2 signaling promotes the reduction of nuclear p27 protein levels through the increased protein expression of SKP-2. These are the first data to demonstrate a role for mTOR in the regulation of SKP-2. In concordance with these findings, mTORC2 activity promotes cell proliferation of RCC cells at the G1-S interphase of the cell cycle. Collectively, these data implicate mTORC2 signaling in the regulation of the SKP-2/p27 axis, a signaling node commonly altered in cancer.

Production of IL-4 and leukemia inhibitory factor by T cells of the cumulus oophorus: a favorable microenvironment for pre-implantation embryo development.

The nature and the functional activity of immunocytes present in the cumulus oophorus, a mass of cells surrounding the oocyte, were examined here for the first time. The cumuli oophorus were obtained from women who had taken part in an in vitro fertilization program and were suffering from blocked fallopian tubes. Both macrophages and CD4(+) T cells were detected in all cumuli. CD4(+) T cell clones, generated from T cells of these cumuli, showed higher potential to produce IL-4 and leukemia inhibitory factor (LIF) than CD4(+) T cell clones generated from peripheral blood or ovary specimens from the same women. More importantly, IL-4 and LIF, but not IFN-gamma mRNA was found to be constitutively expressed in vivo by cumulus oophorus cells. Progesterone is highly produced by the cumulus oophorus/oocyte complex. We recently showed that progesterone up-regulates the production of LIF by T cells and that the progesterone-induced LIF production is mediated by IL-4. Progesterone produced by cumulus granulosa cells may favor IL-4 production by T cells, which in turn can produce LIF. As the treatment with LIF enhances the in vitro growth and development of mammalian embryos, our data suggest that T cells present in the cumulus oophorus produce cytokines that may provide a microenvironment suitable for pre-implantation development of the mammalian embryo.

Recovery of developmentally defined gene sets from high-density cDNA macroarrays.

New technologies for isolating differentially expressed genes from large arrayed cDNA libraries are reported. These methods can be used to identify genes that lie downstream of developmentally important transcription factors and genes that are expressed in specific tissues, processes, or stages of embryonic development. Though developed for the study of gene expression during the early embryogenesis of the sea urchin Strongylocentrotus purpuratus, these technologies can be applied generally. Hybridization parameters were determined for the reaction of complex cDNA probes to cDNA libraries carried on six nylon filters, each containing duplicate spots from 18,432 bacterial clones (macroarrays). These libraries are of sufficient size to include nearly all genes expressed in the embryo. The screening strategy we have devised is designed to overcome inherent sensitivity limitations of macroarray hybridization and thus to isolate differentially expressed genes that are represented only by low-prevalence mRNAs. To this end, we have developed improved methods for the amplification of cDNA from small amounts of tissue (as little as approximately 300 sea urchin embryos, or 2 x 10(5) cells, or about 10 ng of mRNA) and for the differential enhancement of probe sequence concentration by subtractive hybridization. Quantitative analysis of macroarray hybridization shows that these probes now suffice for detection of differentially expressed mRNAs down to a level below five molecules per average embryo cell.

Defective production of both leukemia inhibitory factor and type 2 T-helper cytokines by decidual T cells in unexplained recurrent abortions.

Leukemia inhibitory factor is essential for embryo implantation, and a shift from type 1 T-helper to type 2 T-helper response at the fetal-maternal interface may contribute to successful pregnancy. We show that LIF production is associated with type 2 T-helper cells, is upregulated by IL-4 and progesterone and is downregulated by IL-12, IFN-gamma and IFN-alpha. We also show a decreased production of LIF, IL-4 and IL-10 by decidual T cells of women with unexplained recurrent abortions in comparison with that of women with normal gestation. The defective production of LIF and/or type 2 T-helper cytokines may contribute to the development of unexplained recurrent abortions.

Prevalence and biological effects of anti-trophoblast and anti-endothelial cell antibodies in patients with recurrent spontaneous abortions.

PROBLEM: Trophoblasts and endothelial cells represent a potential target for antibodies in women with recurrent spontaneous abortions. These antibodies have been shown to be associated with anti-phospholipid antibodies. Are they also present in women with unexplained pregnancy losses in the absence of anti-phospholipid antibodies? METHOD OF STUDY: The anti-trophoblast antibodies were tested by an immunofluorescence assay on cells purified from pooled first-trimester placentae, whereas the anti-endothelial cell antibodies were measured by enzyme-linked immunoadsorbent assay (ELISA) on cells isolated from the umbilical vein and were cultured to confluence. The cytotoxicity of trophoblasts was evaluated in a homologous system. The expression of adhesion molecules on endothelial cells was quantitated by ELISA using specific monoclonal antibodies, and the expression of tissue factor was quantitated by a chromogenic assay measuring the formation of factor Xa. RESULTS AND CONCLUSIONS: Complement-fixing antibodies to trophoblast represent a better marker to discriminate patients with recurrent spontaneous abortions from controls and are cytotoxic for the target cells. Anti-endothelial antibodies are also present in these patients and exhibit pro-inflammatory and pro-coagulant activities.

Effect of guanine nucleotides on [3H]glutamate binding and on adenylate cyclase activity in rat brain membranes.

GMP-PNP, a non-hydrolyzable analog of GTP binds tightly to G-protein in the presence of Mg2+, so that the binding is stable even after exhaustive washings. This property was exploited to prepare membrane samples of rat brain where G-protein GTP-binding sites were saturated with GMP-PNP. Experiments carried out with these membranes showed that GTP, GMP-PNP, GDP-S and GMP (1 mM) inhibit the sodium-independent [3H]glutamate binding by 30-40% [F(4,40) = 5.9; p < .001], whereas only GMP-PNP activates adenylate cyclase activity [F(6,42) = 3.56; p < .01]. The inhibition of sodium-independent [3H]glutamate binding occurred in the absence of Mg2+. These findings suggest that guanine nucleotides may inhibit glutamate binding and activate adenylate cyclase through distinct mechanisms by acting on different sites.

Abnormal production of T helper 2 cytokines interleukin-4 and interleukin-5 by T cells from newborns with atopic parents.

T cell clones were generated from umbelical cord blood lymphocytes (UCBL) of nine newborns with atopic or nonatopic parents and their cytokine secretion profile was assessed. Both phytohemagglutinin-induced and Dermatophagoides pteronyssinus-specific T cell clones from newborns with atopic parents exhibited an enhanced ability to produce the Th2 cytokines interleukin (IL)-4 and IL-5, compared to T cell clones from newborns with nonatopic parents. In contrast, the ability to produce interferon-gamma by UCBL from the two groups of newborns was not different. Of the five children who could be followed up to 3 years after birth, four with atopic parents developed clinical and/or biological atopic manifestations, whereas one without atopic parents did not. Thus, the pronounced production of IL-4 and IL-5 by UCBL not only appears to be related to the atopic status of parents, but also associates with the subsequent development of atopy in childhood.

Progesterone favors the development of human T helper cells producing Th2-type cytokines and promotes both IL-4 production and membrane CD30 expression in established Th1 cell clones.

The effect of progesterone (P) on the cytokine production profile of Ag-specific human CD4+ T cell lines and clones was investigated. T cell lines specific for purified protein derivative or streptokinase (SK) derived in the presence of P exhibited significant increased ability to produce IL-5 in comparison with T cell lines derived in the absence of P. Moreover, IL-4 was significantly increased in SK-specific T cell lines derived in the presence of P in comparison with SK-specific T cell lines derived in the absence of this hormone. In addition, SK-specific T cell lines generated in the presence of P developed into T cell clones showing a Th0-, instead of Th1-like, cytokine profile. Furthermore, SK-specific T cell clones with an established Th1 profile of cytokine secretion did express mRNA for, and produced detectable amounts of, IL-4 when stimulated with P in combination with insoluble anti-CD3 mAb. Combined stimulation with P and insoluble anti-CD3 mAb also enabled Th1 clones to express CD30 on their surface membrane. These results indicate that P can favor the development of Th cells producing Th2-type cytokines and is an inducer of both transient IL-4 production and CD30 expression in established Th1 cells. Thus, P production at the placental level may be responsible, at least in part, for increased production of Th2-type cytokines which have been implied in fetal allograft survival and maintenance of successful pregnancy.

Patterns of Pap smear use in the Rimini area: an analysis of women's attitudes to the test.

The use of the Pap test is a method of the prevention of cervical cancer in our local division of the Sanitary Unit and has been studied with the help of a questionnaire which was completed by women who had adopted this test. The socioeconomic characteristics, level of education, occupation and general attitudes regarding the Pap test as well as how the women had acquired knowledge of the test, have all been examined. From an analysis of the answers, we have been able to trace a precise social, economic and cultural profile of the type of women who take advantage of this test. Principally, we are dealing with women aged 40-49 years, often with children, with a medium to low level of education, who are mainly housewives and white-collar workers. Very few elderly women present themselves for the Pap test. We have noticed that there is a direct decrease in the use of preventive methods, proportional to the increase in age. These results demonstrate that an erratic use of this preventive method, in the absence of an organized screening programme, seems only to involve women who are among those at less risk from cervical cancer.

Immunologic infertility: a basic review.

Antisperm antibodies interfere with the human reproductive events and once they have been produced, antisperm antibodies bind to the spermatic surface and affect both the transport of spermatozoa and the interactions between the gametes. The formation of antisperm antibodies has still not been completely explained and the antigen map of the spermatic surface has not been yet established. The antibody levels in the serum generally do not reflect the immunoglobulin present in the secretions of reproductive tract and in the immunologic screening of the infertile couple we need of direct analysis of antisperm antibodies on the spermatic surfaces. We have many diagnostic procedures but actually very few therapeutic options: to improve the last question, a better understanding of the phenomena that lead to fertilization is imperative.

Lupus anticoagulant and monocyte procoagulant activity in polyabortive women.

Monocyte stimulation may be induced by various agents. Monocytes generate procoagulant activity (PCA) in response to stimulation; they widely interact with the hemostatic system and participate in thrombin formation. Extensive placental thrombotic infarction has been implicated in fetal death in polyabortive patients with lupus anticoagulant (LA). We investigated 38 polyabortive women: 17 LA negative (LA-) and 18 LA positive (LA+). We compared the results with 25 clinically normal women. After four hours of incubation, the mean value of monocyte PCA in the LA+ women was significantly higher than in either the LA- or the control group (p < 0.0001). The monocyte PCA was out of the range of the controls in 9 of the 18 LA+ women. No correlation was observed between the levels of LA and monocyte PCA (r = 0.02; p = 0.94). No differences were found in monocyte PCA increase when induced by LA-, LA+ or control plasma; in all cases the increase was about five-six fold. Our results indicate that an increased monocyte PCA is present in some LA+ polyabortive women, thus suggesting that monocyte activation might be involved in the formation of thrombotic placental infarction and the consequent fetal loss in some patients. It might also suggest that these patients, in particular, could benefit from corticosteroid treatment, which is known to inhibit the formation of monocyte PCA.

Prevention of miscarriage in antiphospholipid syndrome.

Recurrent adverse pregnancy outcome may be the final result of different causes, including autoimmune diseases, as the Antiphospholipid Syndrome. Antiphospholipid antibodies (lupus anticoagulant and/or anticardiolipin antibodies) were found in 16% of 197 patients with prior unexplained recurrent miscarriages. During our study 22 out of 32 antiphospholipid antibodies positive women became pregnant again. To prevent abortion relapses, 16 of them were treated with acetylsalicylic acid (50 mg x 2/day) and/or fluocortolone (20 mg/day for 5 days/week). Such therapy started as soon as pregnancy was diagnosed in 14 patients. Two patients began the therapeutic regimen during the third month of gestation. Six patients, who didn't accept this therapeutic approach, represent our control group. All the 14 early treated patients ended pregnancy with success. The 2 women that began the therapy later presented abortion relapses. Among the 6 not treated patients, 5 presented spontaneous abortion and only one gave birth to a baby. No side effect was observed neither in treated mothers nor in their babies. In conclusion, even if further studies would be necessary to standardise a therapeutic protocol, our results encourage the clinical care of patients with antiphospholipid antibodies and adverse pregnancy outcomes.

Does intraperitoneal insemination in the absence of prior sensitization carry with it a risk of subsequent immunity to sperm?

To evaluate the occurrence of antisperm antibodies in women, with no prior sensitization, 112 couples undergoing intraperitoneal insemination were tested for serum antisperm antibodies with the sperm immobilization test (SIT) and the immunobead test (IBT). A serum sample was taken from each of the 112 patients immediately before the first intraperitoneal insemination. Another sample was taken from 58 patients who underwent a second insemination procedure. In 16 of the 58 patients the IBT results were positive for one or more immunoglobulin classes. Five patients showed positive SITs. In 7 out of these 16 subjects (12%) the antibodies were bound to the head and to the shaft of the sperm tail. Five of the six patients submitted to a third intraperitoneal insemination procedure showed unchanged SIT values and IBT binding percentages. In one subject, SIT (6 months after the third insemination) became negative. Antibody production may be either a transient response to massive antigen stimulation or the first step toward systemic immunity.