423 research outputs found

    Annealing of Fused Filament Fabricated Nylon 6 with Elevated Isostatic Pressure

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    Fused filament fabrication (FFF) is the most common form of 3D-printing used today. It combines ease-of-use with broad material options that allow for a wide spectrum of applications. Parts made this way are still considered only prototypes due to their relatively weak strength as compared to traditional manufacturing methods. Two factors leading to a decrease in strength are the interior voids and poor bonding roads. A chamber was created to implement pressurized annealing cycles on nylon 6 co-polymer parts to decrease interior voids and increase road bonding. A designed experiment was used to determine main effect parameter estimates for five factors: annealing time, temperature and pressure, cooling rate, and pressurized cooling. The results showed that with 800 psig of applied pressure during annealing, a significant closing of voids is possible. Annealing in a confined environment led to no noticeable part distortions. The increased density of the parts did not lead to increased yield strength in tension or bending and ultimately made the parts much more brittle. There was found to be a small increase in crystallinity and tensile modulus with small effect sizes. The impact energy absorption capability of the parts was also decreased. After the screening experiment, a validation study was then done to assess the annealing process in the absence of pressure and confining medium. These tests showed significant increase in part performance in both tension and flexion. These in air annealed parts did suffer from increased part distortion. These first look results of elevated isostatic pressure annealing indicate that pressurized annealing may be a viable post-processing technique for FFF parts. Great care needs to be taken when exposing parts to elevated pressure. The annealing process has been further verified to be an avenue to stronger FFF parts

    Soluble CD40L and cardiovascular risk in asymptomatic low-grade carotid stenosis

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    Background and Purpose-We investigated whether soluble CD40L (sCD40L) may predict the risk of cardiovascular (CV) events in patients with asymptomatic carotid plaques. Methods-Forty-two patients with asymptomatic low-grade carotid stenosis (ALCS) and 21 controls without any carotid stenosis were enrolled. All subjects had at least a major cardiovascular risk factor (CRF). Plasma levels of C-reactive protein (CRP), IL-6, and sCD40L were measured. Subjects were reviewed every 12 months (median follow-up, 8 years). Results-ALCS patients had higher (P<0.0001) CRP, IL-6, and sCD40L than controls. Fourteen patients experienced a CV event. Cox regression analysis showed that only high sCD40L levels (P=0.003) independently predicted cardiovascular risk. Conclusions-High levels of sCD40L may predict the risk of CV events in ALCS

    Survival of a sars-cov-2 surrogate on flow-pack polyethylene and polystyrene food trays at refrigeration and room temperature conditions

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    Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the etiological agent of the current pandemic referred to as coronavirus disease 2019, is spread by direct and indirect transmission between humans, including contact with contaminated surfaces, frozen food, packaging materials, and storage environments. Food contamination may occur in the “farm-to-table” lifecycle through contact with food handlers and environments. In the present study, the survival of a SARS-CoV-2 surrogate (feline coronavirus (FCoV)) at room temperature and refrigeration conditions for different time intervals on two types packaging widely used packaging, namely flow-pack polyethylene and polystyrene food trays, was investigated. FCoV was stable on the flow-pack polyethylene for 48 h and 120 h at room temperature and 4◦C, respectively, while it persisted on polystyrene food trays for 36 h at room temperature and for 120 h at +4◦C. The results of our study highlight the possible implications of food packaging in the spread of SARS-CoV-2 during the current pandemic

    Scheduling of Remote Monitoring for Peritoneal Dialysis Patients

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    Peritoneal dialysis (PD) is performed as a home-based treatment and in this context, telemedicine has been proven helpful for improving clinicians’ surveillance and maintaining PD patients in their home setting. The new e-health devices make remote patient monitoring (RPM) for automated peritoneal dialysis (APD) treatment possible, evaluating the data at the end of every treatment and adapting the prescription at distance if necessary. This paper aims to share a method for improving clinical surveillance and enabling PD patients to receive their treatment at home. In the present case series, we delineate the clinical protocol of the Vicenza PD Center regarding patient characteristics, timing, and the purpose of the APD-RPM. We present the Vicenza PD Center’s experience, illustrating its application through three case reports as exemplars. Telemedicine helps to carefully allocate healthcare resources while removing the barriers to accessing care. However, there is a risk of data overload, as some data might not be analyzed because of an increased workload for healthcare professionals. A proactive physician’s attitude towards the e-health system has to be supported by clinical instructions and legislative rules. International and national guidelines may suggest which patients should be candidates for RPM, which parameters should be monitored, and with what timing. According to our experience, we suggest that the care team should define a workflow that helps in formulating a correct approach to RPM, adequately utilizing resources. The workflow has to consider the different needs of patients, in order to assure frequent remote control for incident or unstable patients, while prevalent and stable patients can perform their home treatment more independently, helped by periodic and deferred clinical supervision

    Ongoing Peritoneal Dialysis Training at Home Allows for the Improvement of Patients’ Empowerment: A Single Center Experience

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    Introduction: Peritoneal dialysis (PD), as a home treatment, ensures better patient autonomy and lower intrusiveness compared to hemodialysis. However, choosing PD comes with an increased burden of responsibility that the patient may not always be able to bear, due to advanced age and deteriorating health condition. Various approaches have been explored to address this issue and mitigate its primary complications. In this study, we aim to present the ongoing PD training at-home program implemented by the Vicenza PD Center, and evaluate its impact on patients' prognoses. Material and Methods: We enrolled 210 patients who underwent PD at Vicenza Hospital between 1 January 2019 and 1 January 2022 for a minimum of 90 days. Each patient was observed retrospectively for one year. We categorized the patients into three groups based on their level of autonomy regarding their PD management: completely independent patients; patients able to perform some parts of the PD method on their own, while the remaining aspects were carried out by a caregiver; and patients who required complete assistance from a caregiver, like in the assisted PD program (asPD). Results: A total of 70% of the PD population were autonomous regarding their PD therapy, 14% had an intermediate degree of autonomy, and 16% were entirely dependent on caregivers. The PD nurses performed a median of four home visits per patient per year, with a tendency to make more visits to patients with a lower degree of autonomy. All the groups achieved similar clinical outcomes. At the end of the year of observation, only 6% of the patients witnessed a decline in their autonomy level, whereas 7% demonstrated an enhancement in their level of autonomy, and 87% remained stable. Conclusions: A home care assistance program ensures clinical support to a household with the purpose of improving the empowerment of the PD population and reducing the prevalence of assisted PD. Ongoing PD training at home helps patients to maintain a stable degree of autonomy and stay in their home setting, even though they present with relative attitudinal or social barriers

    Carbonium vs. carbenium ion-like transition state geometries for carbocation cyclization – how strain associated with bridging affects 5-exo vs. 6-endo selectivity

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    Quantum chemical calculations are used to explore the origins of regioselectivity for proton-, Pt(II)- and Pd(II)-promoted cyclizations of 1,5-hexadienes, 5-aminoalkenes, and allylic acetimidates. The strain associated with achieving carbonium ion-like transition state geometries is shown to be a key factor in controlling 5-exo vs. 6-endo selectivity

    ANKRd44 gene silencing: A putative role in trastuzumab resistance in HER2-like breast cancer

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    Trastuzumab is an effective therapeutic treatment for Her2-like breast cancer; despite this most of these tumors develop resistance to therapy due to specific gene mutations or alterations in gene expression. Understanding the mechanisms of resistance to Trastuzumab could be a useful tool in order to identify combinations of drugs that elude resistance and allow a better response for the treated patients. Twelve primary biopsies of Her2+/hormone receptor negative (ER-/PgR-) breast cancer patients were selected based on the specific response to neoadjuvant therapy with Trastuzumab and their whole exome was sequenced leading to the identification of 18 informative gene mutations that discriminate patients selectively based on response to treatment. Among these genes, we focused on the study of the ANKRD44 gene to understand its role in the mechanism of resistance to Trastuzumab. The ANKRD44 gene was silenced in Her2-like breast cancer cell line (BT474), obtaining a partially Trastuzumab-resistant breast cancer cell line that constitutively activates the NF-kb protein via the TAK1/AKT pathway. Following this activation an increase in the level of glycolysis in resistant cells is promoted, also confirmed by the up-regulation of the LDHB protein and by an increased TROP2 protein expression, found generally associated with aggressive tumors. These results allow us to consider the ANKRD44 gene as a potential gene involved in Trastuzumab resistance

    ANKRd44 gene silencing: a putative role in trastuzumab resistance in HER2-like breast cancer

    Get PDF
    Trastuzumab is an effective therapeutic treatment for Her2-like breast cancer; despite this most of these tumors develop resistance to therapy due to specific gene mutations or alterations in gene expression. Understanding the mechanisms of resistance to Trastuzumab could be a useful tool in order to identify combinations of drugs that elude resistance and allow a better response for the treated patients. Twelve primary biopsies of Her2+/hormone receptor negative (ER-/PgR-) breast cancer patients were selected based on the specific response to neoadjuvant therapy with Trastuzumab and their whole exome was sequenced leading to the identification of 18 informative gene mutations that discriminate patients selectively based on response to treatment. Among these genes, we focused on the study of the ANKRD44 gene to understand its role in the mechanism of resistance to Trastuzumab. The ANKRD44 gene was silenced in Her2-like breast cancer cell line (BT474), obtaining a partially Trastuzumab-resistant breast cancer cell line that constitutively activates the NF-kb protein via the TAK1/AKT pathway. Following this activation an increase in the level of glycolysis in resistant cells is promoted, also confirmed by the up-regulation of the LDHB protein and by an increased TROP2 protein expression, found generally associated with aggressive tumors. These results allow us to consider the ANKRD44 gene as a potential gene involved in Trastuzumab resistance

    Aptamers that recognize drug-resistant HIV-1 reverse transcriptase

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    Drug-resistant variants of HIV-1 reverse transcriptase (RT) are also known to be resistant to anti-RT RNA aptamers. In order to be able to develop diagnostics and therapies that can focus on otherwise drug-resistant viruses, we have isolated two aptamers against a well-known, drug-resistant HIV-1 RT, Mutant 3 (M3) from the multidrug-resistant HIV-1 RT panel. One aptamer, M302, bound M3 but showed no significant affinity for wild-type (WT) HIV-1 RT, while another aptamer, 12.01, bound to both M3 and WT HIV-1 RTs. In contrast to all previously selected anti-RT aptamers, neither of these aptamers showed observable inhibition of either polymerase or RNase H activities. Aptamers M302 and 12.01 competed with one another for binding to M3, but they did not compete with a pseudoknot aptamer for binding to the template/primer cleft of WT HIV-1 RT. These results represent the surprising identification of an additional RNA-binding epitope on the surface of HIV-1 RT. M3 and WT HIV-1 RTs could be distinguished using an aptamer-based microarray. By probing protein conformation as a correlate to drug resistance we introduce an additional and useful measure for determining HIV-1 drug resistance
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