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1.
Anal Chim Acta ; 1316: 342815, 2024 Aug 08.
Article in English | MEDLINE | ID: mdl-38969420

ABSTRACT

BACKGROUND: Capillary electrophoresis (CE) has the advantage of rapid anion analysis, when employing a reverse electroosmotic flow (EOF). The conventional CE method utilizes dynamic coatings with surfactants like cetyltrimethylammonium bromide (CTAB) in the run buffer to reverse the EOF. However, this method suffers from very slow equilibration leading to drifting effective migration times of the analyte anions, which adversely affects the identification and quantification of peaks. Permanent coating of the capillary surface may obviate this problem but has been relatively little explored. Thus, permanent capillary surface modification by the covalent binding of 3-aminopropyltriethoxysilane (APTES) was studied as an alternative. RESULTS: This study investigates the effect of APTES concentration for surface functionalization on EOF mobility, separation efficiency, and reproducibility of anion separation. The performance data was complemented by X-ray photoelectron spectroscopy (XPS) and contact angle (CA) measurements. The XPS measurements showed that the coverage with APTES was dependent on its concentration in the coating solution. The XPS measurements correlated well with the EOF values determined for the capillaries tested. A standard mixture of 21 anions could be baseline separated within 10 min in the capillaries with lower EOF, but not in the capillary with the highest EOF as the residence time of the analytes was too short in this case. Compared to conventional dynamic coating with CTAB, APTES-functionalized capillaries provide faster equilibration and long-term EOF stability. The application of APTES-functionalized capillaries in analyzing different beverages demonstrates the precision, reliability, and specificity in determining organic anions, providing valuable insights of their compositions. SIGNIFICANCE: APTES coating on capillaries provides a facile approach to achieve a permanent reversal of the stable EOF to determine anions. The control of the coverage via the concentration of the reagent solution allows the tailoring of the EOF to different needs, a faster EOF for less complex samples where resolution is not challenging, while a lower EOF for higher complex samples where the focus is on separation efficiency. This enhancement in efficiency and sensitivity has been applied to analyzing organic acids in several beverages.

2.
J Neurochem ; 2024 Jul 08.
Article in English | MEDLINE | ID: mdl-38978454

ABSTRACT

The presynapse performs an essential role in brain communication via the activity-dependent release of neurotransmitters. However, the sequence of events through which a presynapse acquires functionality is relatively poorly understood, which is surprising, since mutations in genes essential for its operation are heavily implicated in neurodevelopmental disorders. We addressed this gap in knowledge by determining the developmental trajectory of synaptic vesicle (SV) recycling pathways in primary cultures of rat hippocampal neurons. Exploiting a series of optical and morphological assays, we revealed that the majority of nerve terminals displayed activity-dependent calcium influx from 3 days in vitro (DIV), immediately followed by functional evoked exocytosis and endocytosis, although the number of responsive nerve terminals continued to increase until the second week in vitro. However, the most intriguing discovery was that activity-dependent bulk endocytosis (ADBE) was only observed from DIV 14 onwards. Importantly, optimal ADBE recruitment was delayed until DIV 21 in Fmr1 knockout neurons, which model Fragile X Syndrome (FXS). This implicates the delayed recruitment of ADBE as a potential contributing factor in the development of circuit dysfunction in FXS, and potentially other neurodevelopmental disorders.

3.
J Pediatr Orthop ; 2024 Jul 09.
Article in English | MEDLINE | ID: mdl-38979941

ABSTRACT

BACKGROUND: Given the rare nature of tibial tubercle fractures, previous studies are mostly limited to small, single-center series. This results in practice variation. Previous research has shown poor surgeon agreement on utilization of advanced imaging, but improved evidence-based indications may help balance clinical utility with resource utilization. The purpose of this study is to quantify diagnostic practices for tibial tubercle fractures in a large, multicenter cohort, with attention to the usage and impact of advanced imaging. METHODS: This is a retrospective series of pediatric tibial tubercle fractures from 7 centers between 2007 and 2022. Exclusion criteria were age above 18 years, missing demographic and pretreatment data, closed proximal tibial physis and tubercle apophysis, or a proximal tibia fracture not involving the tubercle. Demographic and injury data were collected. Fracture classifications were derived from radiographic evaluation. The utilization of advanced imaging was recorded as well as the presence of findings not identified on radiographs. Standard descriptive statistics were reported, and χ2 tests were performed (means reported±SD). RESULTS: A total of 598 patients satisfied the inclusion criteria, of which 88.6% (530/598) were male with a mean age of 13.8±1.9 years. Internal oblique x-rays were obtained in 267 patients (44.6%), computed tomography (CT) in 158 (26.4%), and magnetic resonance imaging (MRI) in 64 (10.7%). There were significant differences in the frequency at which CT (7.2% to 79.4%, P<0.001) and MRI were obtained (1.5% to 54.8%, P<0.001). CT was obtained most frequently for Ogden type IV fractures (50/99, 50.5%), and resulted in novel findings that were not visualized on radiographs in a total of 37/158 patients (23.4%). The most common finding on CT was intra-articular fracture extension (25/37). MRI was obtained most frequently for Ogden type V fractures (13/35, 37.1%), and resulted in novel findings in a total of 31/64 patients (48.4%). The most common finding was patellar tendon injury (11/64), but only 3 of these patients required tendon repair. CONCLUSIONS: Substantial variation exists in the diagnostic evaluation of tibial tubercle fractures. CT was most helpful in clarifying intra-articular involvement, while MRI can identify patellar tendon injury, periosteal sleeve avulsion, or a nondisplaced fracture. This study quantifies variation in diagnostic practices for tibial tubercle fractures, highlighting the need for evidence-based indications for advanced imaging. LEVEL OF EVIDENCE: Level III.

4.
Pathology ; 2024 Jun 20.
Article in English | MEDLINE | ID: mdl-38981818

ABSTRACT

Infections caused by vancomycin-resistant enterococci (VRE) are common. Real-time PCR assays targeting vanA and vanB facilitate screening of patients in healthcare settings to limit the risk of dissemination, especially amongst those at high-risk of infection or with limited treatment options. Such assays are commonly performed as reflex testing procedures where they augment phenotypic techniques and shorten turnaround time to benefit timely clinical management. 'Random access' and 'sample-to-result' real-time PCR platforms are suited for this application as they are of low complexity and less technically demanding. Modelled on these attributes, we configured a real-time PCR assay (VRE BD) for detection of vanA/B in clinical isolates of enterococci, adapted for the BD Max System (Becton Dickinson). We applied an unconventional approach by testing suspensions of microorganisms in water to circumvent the traditional pre-analytical genomic extraction process. Our objective of this study was to assess the performance of this assay for detection of VRE in cultures by validating against a traditional real-time PCR assay based on the LightCycler 2.0 platform (Roche, VRE RO). A high level of analytical sensitivity and specificity (≥99.0%) for both genes was obtained when testing suspensions derived from blood agar. Results for suspensions obtained from chromID VRE (Edwards Group) showed a similar level of performance for vanA detection (100%), but not for the vanB target (≥90.9%) where a lesser number of isolates were available for testing. However, our results for VRE detection in isolates from these media were repeatable and reproducible, and equated to positive and negative predictive values of ≥95.2% and ≥97.8%, respectively. Furthermore, the VRE BD assay was also able to accurately detect VRE in clinical and spiked BacT/ALERT (bioMérieux) blood cultures. Thus, the technical simplicity, short turnaround time and robustness of this high performing assay for VRE is suitable for reflex testing. In addition, the format developed for the BD Max platform has potential application for reflex testing other molecular targets of clinical importance.

5.
Laryngoscope ; 2024 Jul 10.
Article in English | MEDLINE | ID: mdl-38982872

ABSTRACT

OBJECTIVE: The shape of esophageal dilators has not changed in over 350 years. Clinical and animal research suggests that the upper esophageal sphincter (UES) is not round but approximates a kidney shape and that cylindrical dilators may be suboptimal. The Infinity UES Dilation System has been developed specifically for the anatomic configuration of the UES. This study evaluates the safety of the UES-specific Infinity Dilation System. METHODS: All patients undergoing dilation of the UES between January 1, 2022 and September 1, 2023 were included. Demographics, procedure indication, dilator type, minor adverse events, and major complications were abstracted. Minor adverse events, complications, and maximum dilation dimension (mm) were compared between groups. RESULTS: A total of 477 patients were included. Eight hundred and seventy-three total UES dilations were performed. The primary indications for UES dilation were cricopharyngeus muscle dysfunction (43%) and stenosis from radiation toxicity (40%). Twenty-three percent (202/873) of dilations were performed with an Infinity balloon, 31% (270/873) were performed using two conventional balloons placed side by side, and 46% (401/873) were performed with one singleton conventional balloon. The average maximum dilation dimension was 33 (±4.7) mm for Infinity balloons, 32 (±3.8) mm for two side-by-side balloons, and 18 (±3.4) mm for singleton balloons. There were three major complications with conventional balloons and none with Infinity balloons. There were no significant differences in minor adverse events between groups. CONCLUSIONS: A UES-specific esophageal dilator provides a greater maximum dilation dimension and appears to be at least as safe as dilation with a single cylindrical balloon designed to dilate the esophagus. LEVEL OF EVIDENCE: Level 3 Laryngoscope, 2024.

6.
Rheumatol Ther ; 2024 Jul 10.
Article in English | MEDLINE | ID: mdl-38985247

ABSTRACT

INTRODUCTION: High baseline neutrophil-to-lymphocyte ratio (NLR) in rheumatoid arthritis (RA) has been associated with positive responses to biologic tumor necrosis factor inhibition and negative responses to conventional synthetic disease-modifying antirheumatic drug (csDMARD) triple therapy. Datasets from three randomized clinical trials in patients with RA were used to test the hypothesis that baseline NLR is associated with improved clinical response to filgotinib in methotrexate (MTX)-naïve or MTX-experienced RA populations. METHODS: Patients from FINCH 1 (inadequate response to MTX, MTX-IR; NCT02889796), FINCH 2 (inadequate response to biologic DMARDs; NCT02873936), and FINCH 3 (MTX-naïve; NCT02886728) were classified as baseline NLR-High or baseline NLR-Low based on a previously published cut point of 2.7. In total, 3365 patients were included across the three studies. Differences in clinical outcomes and patient-reported outcomes (PROs) were determined using linear-regression models. RESULTS: Control-arm patients (placebo + MTX/placebo + csDMARD) classified as NLR-High exhibited worse continuous clinical and PRO responses at week 12 across clinical trials compared to NLR-Low patients. In contrast, NLR-High patients who received FIL 200 mg + MTX/csDMARD exhibited consistently better responses after 12 weeks compared to NLR-Low patients across clinical trials, clinical endpoints, and PROs. These trends were most prominent among the MTX-IR population. CONCLUSION: The 2.7 baseline NLR cut point could be used to enrich for patients most likely to benefit from the addition of filgotinib to background MTX/csDMARD. Use of baseline NLR as part of therapeutic decision-making would not require additional diagnostics and could contribute to improved outcomes for patients with RA. TRIAL REGISTRATION: Clinicaltrials.gov: NCT02889796; NCT02873936; NCT02886728.


Rheumatoid arthritis is a disease that results in swollen and painful joints. There is currently no method to determine which treatment will work best for an individual patient. However, there may be identifying markers found in the blood that could indicate how a patient will respond to treatment. One of these possible markers is a ratio of two types of white blood cells, neutrophils and lymphocytes, which are part of the body's immune system and help the body detect and fight infection and other diseases. This ratio is referred to as the neutrophil-to-lymphocyte ratio. The current study evaluated whether the neutrophil-to-lymphocyte ratio at the beginning of treatment was associated with rheumatoid arthritis treatment outcomes. Blood test results were used from 3365 patients receiving filgotinib (a medicine used to treat rheumatoid arthritis) or other therapies as part of the FINCH clinical trials. Patients were classified as having a high or low neutrophil-to-lymphocyte ratio at the start of treatment. Patients receiving filgotinib over 24 weeks who had a high neutrophil-to-lymphocyte ratio showed less disease activity than patients whose ratio was low. This study provides support for the use of the neutrophil-to-lymphocyte ratio as a way to help determine whether a patient would benefit from filgotinib as part of their rheumatoid arthritis treatment and may help improve rheumatoid arthritis treatment outcomes.

7.
J Hand Surg Am ; 2024 Jul 18.
Article in English | MEDLINE | ID: mdl-39023500

ABSTRACT

Spastic elbow deformity in patients with upper motor neuron injuries results from an imbalance of flexor and extensor forces across the ulnohumeral joint. Although not all deformities reflect the same underlying imbalances, the elbow most commonly rests in a flexed position. Patients may present with a combination of muscle spasticity, myostatic contracture, and/or joint contracture. A focused history and physical examination are essential for developing individualized surgical plans that account for variations in deformity severity and patient goals. Patients may present with or without volitional control; goals and treatment options differ depending on the degree of control present. Techniques include hyperselective neurectomy, tendon lengthening, muscle origin release, myotomy, tenotomy, periarticular soft tissue release, and skin rearrangement. This article presents a comprehensive review of the surgical approach to the volitional and nonvolitional spastic elbow deformities.

8.
Future Oncol ; : 1-13, 2024 Jul 12.
Article in English | MEDLINE | ID: mdl-38995237

ABSTRACT

WHAT IS THIS SUMMARY ABOUT?: This summary describes the results from the TALAPRO-2 research study (also known as a clinical trial). The TALAPRO-2 study tested the combination of two medicines called talazoparib plus enzalutamide. This combination of medicines was used as the first treatment for adult patients with metastatic castration-resistant prostate cancer. The combination of talazoparib plus enzalutamide was compared with a placebo plus enzalutamide. WHAT IS METASTATIC CASTRATION-RESISTANT PROSTATE CANCER?: Metastatic castration-resistant prostate cancer is a type of cancer that starts in the prostate and has spread to other parts of the body. Castration-resistant means that the cancer continues to grow even when testosterone levels in the blood are reduced to very low levels. Taking medicines to lower testosterone levels in the blood is a standard treatment for men with advanced prostate cancer. WHAT ARE THE AIMS OF THE TALAPRO-2 TRIAL?: TALAPRO-2 looked at if combining talazoparib plus enzalutamide would increase the length of time patients lived before their cancer got worse or they died compared with a placebo plus enzalutamide. Researchers looked at how treatment affected the size and number of tumors and the length of time before patients needed to change to a new cancer medicine. Researchers also looked at any side effects patients had during the study. WHAT ARE THE KEY TAKEAWAYS?: A total of 805 patients with metastatic castration-resistant prostate cancer took part in the study. Compared with patients who took a placebo plus enzalutamide, the group of patients who took talazoparib plus enzalutamide had a 37% reduced risk of their cancer getting worse or dying. Some patients had tumors that at the start of the study could be measured with scans. Sixty-two percent of patients who took talazoparib plus enzalutamide had their tumors decrease or shrink to the point that they could no longer be seen on scans versus 44% of patients who took a placebo plus enzalutamide. Patients who took talazoparib plus enzalutamide were more likely to have a longer time before they needed to change to a new cancer medicine. The most common side effects of talazoparib plus enzalutamide were low levels of red blood cells (66% of patients) and neutrophils (36% of patients), and excessive tiredness or exhaustion (34% of patients).Clinical Trial Registration: NCT03395197 (TALAPRO-2) (ClinicalTrials.gov).

9.
Commun Biol ; 7(1): 866, 2024 Jul 16.
Article in English | MEDLINE | ID: mdl-39009734

ABSTRACT

Mycobacteria adapt to infection stresses by entering a reversible non-replicating persistence (NRP) with slow or no cell growth and broad antimicrobial tolerance. Hypoxia and nutrient deprivation are two well-studied stresses commonly used to model the NRP, yet little is known about the molecular differences in mycobacterial adaptation to these distinct stresses that lead to a comparable NRP phenotype. Here we performed a multisystem interrogation of the Mycobacterium bovis BCG (BCG) starvation response, which revealed a coordinated metabolic shift away from the glycolysis of nutrient-replete growth to depletion of lipid stores, lipolysis, and fatty acid ß-oxidation in NRP. This contrasts with BCG's NRP hypoxia response involving a shift to cholesterol metabolism and triglyceride storage. Our analysis reveals cryptic metabolic vulnerabilities of the starvation-induced NRP state, such as their newfound hypersensitivity to H2O2. These observations pave the way for developing precision therapeutics against these otherwise drug refractory pathogens.


Subject(s)
Adaptation, Physiological , Mycobacterium bovis , Mycobacterium bovis/metabolism , Glycolysis , Metabolic Reprogramming
10.
J Control Release ; 373: 105-116, 2024 Jul 12.
Article in English | MEDLINE | ID: mdl-38992622

ABSTRACT

Nanomedicines hold promise for the treatment of various diseases. However, treating cancer metastasis remains highly challenging. In this study, we synthesized gold nanorods (AuNRs) containing (α-GC), an immune stimulator, for the treatment of primary cancer, metastasis, and recurrence of the cancer. Therefore, the AuNR were coated with lipid bilayers loaded with α-GC (α-LA). Upon irradiation with 808 nm light, α-LA showed a temperature increase. Intra-tumoral injection of α-LA in mice and local irradiation of the 4T1 breast cancer tumor effectively eliminated tumor growth. We found that the presence of α-GC in α-LA activated dendritic cells and T cells in the spleen, which completely blocked the development of lung metastasis. In mice injected with α-LA for primary breast cancer treatment, we observed antigen-specific T cell responses and increased cytotoxicity against 4T1 cells. We conclude that α-LA is promising for the treatment of both primary breast cancer and its metastasis.

12.
Evol Appl ; 17(7): e13735, 2024 Jul.
Article in English | MEDLINE | ID: mdl-39006004

ABSTRACT

For almost 200 years, the taxonomy of cutthroat trout (Oncorhynchus clarkii), a salmonid native to Western North America, has been in flux as ichthyologists and fisheries biologists have tried to describe the diversity within these fishes. Starting in the 1950s, Robert Behnke reexamined the cutthroat trout and identified 14 subspecies based on morphological traits, Pleistocene events, and modern geographic ranges. His designations became instrumental in recognizing and preserving the remaining diversity of cutthroat trout. Over time, molecular techniques (i.e. karyotypes, allozymes, mitochondrial DNA, SNPs, and microsatellite arrays) have largely reinforced Behnke's phylogenies, but have also revealed that some relationships are consistently weakly supported. To further resolve these relationships, we generated de novo transcriptomes for nine cutthroat subspecies, as well as a Bear River Bonneville form and two Colorado River lineages (blue and green). We present phylogenies of these subspecies generated from multiple sets of orthologous genes extracted from our transcriptomes. We confirm many of the relationships identified in previous morphological and molecular studies, as well as discuss the importance of significant differences apparent in our phylogenies from these studies within a geological perspective. Specific findings include three distinct clades: (1) Bear River Bonneville form and Yellowstone cutthroat trout; (2) Bonneville cutthroat trout (n = 2); and (3) Greenback and Rio Grande cutthroat trout. We also identify potential gene transfer between Bonneville cutthroat trout and a population of Colorado River green lineage cutthroat trout. Using these findings, it appears that additional groups warrant species-level consideration if other recent species elevations are retained.

13.
Neurooncol Adv ; 6(1): vdae093, 2024.
Article in English | MEDLINE | ID: mdl-38946879

ABSTRACT

Background: Primary CNS lymphoma (PCNSL) and glioblastoma (GBM) both represent frequent intracranial malignancies with differing clinical management. However, distinguishing PCNSL from GBM with conventional MRI can be challenging when atypical imaging features are present. We employed advanced dMRI for noninvasive characterization of the microstructure of PCNSL and differentiation from GBM as the most frequent primary brain malignancy. Methods: Multiple dMRI metrics including Diffusion Tensor Imaging, Neurite Orientation Dispersion and Density Imaging, and Diffusion Microstructure Imaging were extracted from the contrast-enhancing tumor component in 10 PCNSL and 10 age-matched GBM on 3T MRI. Imaging findings were correlated with cell density and axonal markers obtained from histopathology. Results: We found significantly increased intra-axonal volume fractions (V-intra and intracellular volume fraction) and microFA in PCNSL compared to GBM (all P < .001). In contrast, mean diffusivity (MD), axial diffusivity (aD), and microADC (all P < .001), and also free water fractions (V-CSF and V-ISO) were significantly lower in PCNSL (all P < .01). Receiver-operating characteristic analysis revealed high predictive values regarding the presence of a PCNSL for MD, aD, microADC, V-intra, ICVF, microFA, V-CSF, and V-ISO (area under the curve [AUC] in all >0.840, highest for MD and ICVF with an AUC of 0.960). Comparative histopathology between PCNSL and GBM revealed a significantly increased cell density in PCNSL and the presence of axonal remnants in a higher proportion of samples. Conclusions: Advanced diffusion imaging enables the characterization of the microstructure of PCNSL and reliably distinguishes PCNSL from GBM. Both imaging and histopathology revealed a relatively increased cell density and a preserved axonal microstructure in PCNSL.

14.
Front Psychiatry ; 15: 1330993, 2024.
Article in English | MEDLINE | ID: mdl-38947186

ABSTRACT

Introduction: Forensic psychiatric patients receive treatment to address their violent and aggressive behavior with the aim of facilitating their safe reintegration into society. On average, these treatments are effective, but the magnitude of effect sizes tends to be small, even when considering more recent advancements in digital mental health innovations. Recent research indicates that wearable technology has positive effects on the physical and mental health of the general population, and may thus also be of use in forensic psychiatry, both for patients and staff members. Several applications and use cases of wearable technology hold promise, particularly for patients with mild intellectual disability or borderline intellectual functioning, as these devices are thought to be user-friendly and provide continuous daily feedback. Method: In the current randomized crossover trial, we addressed several limitations from previous research and compared the (continuous) usability and acceptance of four selected wearable devices. Each device was worn for one week by staff members and patients, amounting to a total of four weeks. Two of the devices were general purpose fitness trackers, while the other two devices used custom made applications designed for bio-cueing and for providing insights into physiological reactivity to daily stressors and events. Results: Our findings indicated significant differences in usability, acceptance and continuous use between devices. The highest usability scores were obtained for the two fitness trackers (Fitbit and Garmin) compared to the two devices employing custom made applications (Sense-IT and E4 dashboard). The results showed similar outcomes for patients and staff members. Discussion: None of the devices obtained usability scores that would justify recommendation for future use considering international standards; a finding that raises concerns about the adaptation and uptake of wearable technology in the context of forensic psychiatry. We suggest that improvements in gamification and motivational aspects of wearable technology might be helpful to tackle several challenges related to wearable technology.

15.
J Rheumatol ; 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38950956

ABSTRACT

The sudden and unanticipated emergence of SARS-Cov-2 at the beginning of the present decade, associated with high morbidity and mortality among people infected, prompted the rapid emergence of telemedicine approaches for the management of patients with rheumatoid arthritis (RA). The rationale was to limit the likelihood for viral contagion in a hospital outpatient setting for people rendered potentially more vulnerable by the immunosuppressive nature of many of the pharmacological interventions in the treatment armamentarium.

17.
Physiol Genomics ; 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38949617

ABSTRACT

Type 2 diabetes (T2D) is a common metabolic disease due to insufficient insulin secretion by pancreatic beta cells in the context of insulin resistance. Islet molecular pathology reveals a role for protein misfolding in beta cell dysfunction and loss with islet amyloid derived from islet amyloid polypeptide (IAPP), a protein co-expressed and co-secreted with insulin. The most toxic form of misfolded IAPP is intracellular membrane disruptive toxic oligomers present in beta cells in T2D and in beta cells of mice transgenic for human IAPP (hIAPP). Prior work revealed a high degree of overlap of transcriptional changes in islets from T2D and pre-diabetic 9-10-week-old mice transgenic for hIAPP with most changes being pro-survival adaptations and therefore of limited therapeutic guidance. Here we investigated islets from hIAPP transgenic mice at an earlier age (6 weeks) to screen for potential mediators of hIAPP toxicity that precede predominance of pro-survival signaling. We identified early suppression of cholesterol synthesis and trafficking along with aberrant intra-beta cell cholesterol and lipid deposits, and impaired cholesterol trafficking to cell membranes. These findings align with comparable lipid deposits present in beta cells in T2D and increased vulnerability to develop T2D in individuals taking medications that suppress cholesterol synthesis.

18.
Materials (Basel) ; 17(13)2024 Jul 04.
Article in English | MEDLINE | ID: mdl-38998387

ABSTRACT

Laser hot wire directed energy deposition (LHW-DED) is a layer-by-layer additive manufacturing technique that permits the fabrication of large-scale Ti-6Al-4V (Ti64) components with a high deposition rate and has gained traction in the aerospace sector in recent years. However, one of the major challenges in LHW-DED Ti64 is heat accumulation, which affects the part quality, microstructure, and properties of as-built specimens. These issues require a comprehensive understanding of the layerwise heat-accumulation-driven process-structure-property relationship in as-deposited samples. In this study, a systematic investigation was performed by fabricating three Ti-6Al-4V single-wall specimens with distinct interlayer delays, i.e., 0, 120, and 300 s. The real-time acquisition of high-fidelity thermal data and high-resolution melt pool images were utilized to demonstrate a direct correlation between layerwise heat accumulation and melt pool dimensions. The results revealed that the maximum heat buildup temperature of the topmost layer decreased from 660 °C to 263 °C with an increase to a 300 s interlayer delay, allowing for better control of the melt pool dimensions, which then resulted in improved part accuracy. Furthermore, the investigation of the location-specific composition, microstructure, and mechanical properties demonstrated that heat buildup resulted in the coarsening of microstructures and, consequently, the reduction of micro-hardness with increasing height. Extending the delay by 120 s resulted in a 5% improvement in the mechanical properties, including an increase in the yield strength from 817 MPa to 859 MPa and the ultimate tensile strength from 914 MPa to 959 MPa. Cooling rates estimated at 900 °C using a one-dimensional thermal model based on a numerical method allowed us to establish the process-structure-property relationship for the wall specimens. The study provides deeper insight into the effect of heat buildup in LHW-DED and serves as a guide for tailoring the properties of as-deposited specimens by regulating interlayer delay.

19.
PLoS One ; 19(7): e0302681, 2024.
Article in English | MEDLINE | ID: mdl-38985795

ABSTRACT

RATIONALE: A common strategy to reduce COPD readmissions is to encourage patient follow-up with a physician within 1 to 2 weeks of discharge, yet evidence confirming its benefit is lacking. We used a new study design called target randomized trial emulation to determine the impact of follow-up visit timing on patient outcomes. METHODS: All Ontario residents aged 35 or older discharged from a COPD hospitalization were identified using health administrative data and randomly assigned to those who received and did not receive physician visit follow-up by within seven days. They were followed to all-cause emergency department visits, readmissions or death. Targeted randomized trial emulation was used to adjust for differences between the groups. COPD emergency department visits, readmissions or death was also considered. RESULTS: There were 94,034 patients hospitalized with COPD, of whom 73.5% had a physician visit within 30 days of discharge. Adjusted hazard ratio for all-cause readmission, emergency department visits or death for people with a visit within seven days post discharge was 1.03 (95% Confidence Interval [CI]: 1.01-1.05) and remained around 1 for subsequent days; adjusted hazard ratio for the composite COPD events was 0.97 (95% CI 0.95-1.00) and remained significantly lower than 1 for subsequent days. CONCLUSION: While a physician visit after discharge was found to reduce COPD events, a specific time period when a physician visit was most beneficial was not found. This suggests that follow-up visits should not occur at a predetermined time but be based on factors such as anticipated medical need.


Subject(s)
Emergency Service, Hospital , Patient Discharge , Patient Readmission , Pulmonary Disease, Chronic Obstructive , Humans , Pulmonary Disease, Chronic Obstructive/therapy , Pulmonary Disease, Chronic Obstructive/epidemiology , Patient Discharge/statistics & numerical data , Male , Female , Aged , Middle Aged , Patient Readmission/statistics & numerical data , Emergency Service, Hospital/statistics & numerical data , Time Factors , Aged, 80 and over , Ontario/epidemiology , Follow-Up Studies , Adult , Hospitalization/statistics & numerical data
20.
Front Cell Dev Biol ; 12: 1389077, 2024.
Article in English | MEDLINE | ID: mdl-38946799

ABSTRACT

The molecular mechanisms that govern the metabolic commitment to reproduction, which often occurs at the expense of somatic reserves, remain poorly understood. We identified the Caenorhabditis elegans F-box protein FBXL-5 as a negative regulator of maternal provisioning of vitellogenin lipoproteins, which mediate the transfer of intestinal lipids to the germline. Mutations in fbxl-5 partially suppress the vitellogenesis defects observed in the heterochronic mutants lin-4 and lin-29, both of which ectopically express fbxl-5 at the adult developmental stage. FBXL-5 functions in the intestine to negatively regulate expression of the vitellogenin genes; and consistently, intestine-specific over-expression of FBXL-5 is sufficient to inhibit vitellogenesis, restrict lipid accumulation, and shorten lifespan. Our epistasis analyses suggest that fbxl-5 functions in concert with cul-6, a cullin gene, and the Skp1-related gene skr-3 to regulate vitellogenesis. Additionally, fbxl-5 acts genetically upstream of rict-1, which encodes the core mTORC2 protein Rictor, to govern vitellogenesis. Together, our results reveal an unexpected role for a SCF ubiquitin-ligase complex in controlling intestinal lipid homeostasis by engaging mTORC2 signaling.

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